Printing Companies
  1. About Printing Industry
  2. Printing Services
  3. Print Buyers
  4. Printing Resources
  5. Classified Ads
  6. Printing Glossary
  7. Printing Newsletters
  8. Contact Print Industry
Who We Are

Printing Industry Exchange (printindustry.com) is pleased to have Steven Waxman writing and managing the Printing Industry Blog. As a printing consultant, Steven teaches corporations how to save money buying printing, brokers printing services, and teaches prepress techniques. Steven has been in the printing industry for thirty-three years working as a writer, editor, print buyer, photographer, graphic designer, art director, and production manager.

Need a Printing Quote from multiple printers? click here.

Are you a Printing Company interested in joining our service? click here.

The Printing Industry Exchange (PIE) staff are experienced individuals within the printing industry that are dedicated to helping and maintaining a high standard of ethics in this business. We are a privately owned company with principals in the business having a combined total of 103 years experience in the printing industry.

PIE's staff is here to help the print buyer find competitive pricing and the right printer to do their job, and also to help the printing companies increase their revenues by providing numerous leads they can quote on and potentially get new business.

This is a free service to the print buyer. All you do is find the appropriate bid request form, fill it out, and it is emailed out to the printing companies who do that type of printing work. The printers best qualified to do your job, will email you pricing and if you decide to print your job through one of these print vendors, you contact them directly.

We have kept the PIE system simple -- we get a monthly fee from the commercial printers who belong to our service. Once the bid request is submitted, all interactions are between the print buyers and the printers.

We are here to help, you can contact us by email at info@printindustry.com.

Blog Articles for PrintIndustry.com

Archive for the ‘Photos’ Category

Custom Printing: Save Photos in RGB (Not CMYK) Format

Sunday, October 10th, 2021

Photo purchased from … www.depositphotos.com

I learned something today. A colleague of mine emailed me saying her book designer planned to save all photos in RGB rather than CMYK format. My colleague asked my opinion. So I did some homework.

I have been using Photoshop since the late ‘80s or early ‘90s. Back then any automatic translation by the commercial print provider from RGB to CMYK was rather problematic, yielding unpredictable and sometimes muddy results. So I, and all the designers I knew or managed, always changed photos from RGB to CMYK when preparing files for commercial printing.

RGB vs. CMYK

First of all, let’s define some terms. RGB (red/green/blue) is the color gamut used for online presentation of art, photos, and text (i.e., anything related to the combining of light rather than ink). Red, green, and blue phosphors create all visible hues on the screen. These are called the additive primaries. In contrast, when you prepare files for offset commercial printing (or printing with any other kind of ink), you use cyan, magenta, yellow, and black ink. These are the subtractive primaries (actually only cyan, magenta, and yellow are the primaries; black is added by printers to darken and give definition to the resulting CMY ink mixture).

When you combine the additive primaries on a computer screen, you get white light. When you add the subtractive primaries using ink, you get black ink (closer to muddy black, but that’s why printers add a separate black ink, as noted above).

Look inside a color laser printer. You’ll see cyan, magenta, yellow, and black toner cartridges. Look at an inkjet printer, and you’ll see cyan, magenta, yellow, and black liquid ink cartridges. Truth be told, if you look at a high-end inkjet printer (like a grand-format flatbed printer), you’ll probably see other colors as well, such as red, green, and blue; or orange and green or purple; or light magenta and light cyan; and maybe even a few different black ink mixtures.

In all of these cases, we’re talking about augmenting the CMYK “color space” when putting toner or ink or any other physical rendering of color on paper or any other substrate. This is in contrast to any colors made with light (even theater lights with gelatin color screens over the bulbs would fit into the RGB model rather than the CMYK model).

So why is this important? How does it relate to your daily design work in Photoshop and InDesign?

Most importantly, the RGB color space has a much wider color gamut than the CMYK color space. You can produce significantly more individual hues. Even though you might want to print in RGB format (but you can’t), you do want to keep photos in RGB format for as long as possible before the final conversion to CMYK prior to commercial printing.

A Wider Color Gamut

At this final transition, by the way, colors in the RGB color gamut that can’t be reproduced via CMYK custom printing will be converted to the nearest printable color. In the late ‘80s and early ‘90s, this transition was less than perfect. Now it is actually more skillfully done by your offset/digital printer’s software than by you.

If you make the change yourself, you can do it in Photoshop, or you can make the change in InDesign when you distill final press-ready PDFs for your commercial printing provider. But if you let him make the change, he can optimize the photos for his own press and for the specific paper (gloss coated, uncoated, etc.) that you’ll be using. This is a lot more precise than just going to the mode command in Photoshop and changing the image from RGB to CMYK.

Custom printing presses also make a difference. If you’re still in an RGB workflow at the last possible moment, it will be easier to optimize output for either web-offset printing or sheetfed-offset printing. If you leave this transition to your commercial printing supplier, you never have to change the photos themselves.

So while it’s understandable that I (and my colleague, who is the same age) and probably a lot of other designers who started working with PageMaker, Illustrator, and Photoshop (30 years ago) would (entirely out of habit) automatically want to convert all photos from RGB to CMYK, even though that might not be the best course of action.

The safest thing to do, in my opinion, is to ask your commercial printing supplier. Different printers may/will probably approach this question differently based on their equipment and expertise. Most, however, will probably ask you to leave the photos in RGB format within an InDesign file. Of course, to be safe you can always provide both a press-ready PDF file and a native InDesign file when you upload your final art. This way, your printer can always go back to the native file to make any changes he needs to make that might not be possible in a PDF file (which is essentially locked down and not as easily modified).

Another Benefit of an RGB Workflow

If you keep your images in RGB format in Photoshop and even in InDesign, you will have the added benefit of being able to easily use the documents online. And, in addition, you may have more success (i.e., rich coloration) when you print to a digital press (let’s say an HP Indigo electrophotographic—laser—press or a large-format inkjet press). Just another reason to consider an RGB image workflow.

When Not to Submit RGB Art to Your Printer

If you’re creating vector art (line art) in Illustrator, use CMYK. InDesign can convert RGB to CMYK in this case, too, but the results are not as predictable for vector images as for pixel-based images. This is especially important to note if your design includes specific logo colors (perhaps CMYK builds to match PMS colors in your logo). In this case you’ll want to have total control over the percentages of cyan, magenta, yellow, and black ink your print provider will use.

The same is true if you are applying color to selected images within an InDesign art file. Use CMYK percentages, not RGB percentages, for the reason noted above.

But don’t forget that if you’re doing anything for computer-screen reproduction, you actually want the final output to be in RGB format, and as an added benefit you get the much wider color gamut noted above.

Final Notes

If you decide to change the images yourself from RGB to CMYK prior to handing off art files to your print provider, ask your vendor for the specific color profile that will take into account the paper you’ve chosen as well as the specific custom printing device he’ll be using to produce the job. Then, in Photoshop, choose Edit/Convert to Profile (instead of just “convert from RGB to CMYK”). In this way you’ll be choosing the most precise and most accurate target specifications for your particular job, and you’ll be less likely to inadvertently omit any colors as “out of color gamut” that might have otherwise printed just fine.

Custom Printing: Selecting the Best Photos for Publication

Wednesday, October 6th, 2021

Photo purchased from … www.depositphotos.com

If you look at the photo above, you’ll see a catastrophe in the making, a tornado just about to strike. It’s a powerful image. It also captures the emotions you might experience if you choose a bad photo for an important promotional piece. Believe me. I have made the mistakes noted below.

More often than not, it’s the photos in a design piece (everything from a print book cover to a multi-floor building wrap) that grab the view’s attention first, before the typescript, the content. Photos grip the viewer, often encouraging her/him to feel or think about a subject in a particular way.

So if you’re a marketer, or even a print book designer, it is crucial that you select the best images for publication. And since these images usually go through some sort of digital or offset commercial printing process, it’s important to remember that printing technology reduces image quality. It does not enhance it.

What Does This Mean?

This can mean a number of things. Most of these pertain to either technical qualities or design qualities. Both subjects could fill several books. So for now I’ll say only a little about the design aspects and then shift to the technical requirements.

  1. As a designer, I choose images that focus on a single subject (a person, group, place, or thing) in a dramatic and unique way, a way that makes a statement.
  2. If the subject is a person, I choose an image that captures the character of the person, and then I crop away all extraneous image material and focus on the person’s face, posture, etc.

Usually, if you review a number of images (JPEGs on a computer, transparencies on a light box, or paper photo prints scattered on a table), only a handful of images will be “right” intuitively in your eyes and those of your colleagues or clients.

The Technical Aspects

Selecting images from a perspective of design is often very subjective. However, once you’ve found your preferred photos, you will want to ensure that they reproduce in the most dramatic and effective way. You don’t want any technical flaws to lessen their impact.

(Back when I started in the business of design and art production, we had no digital images. Therefore, we could only choose photos in either print form on glossy paper or as transparencies, or slides.)

Crisp Focus

Images have to start out in crystal clear focus. An out of focus image draws attention to itself, not to its subject matter. So only choose crisp photos. Granted, a photo will often have a visible depth of field, that is, a range in which everything is in focus and outside of which everything is somewhat blurred. This can be very effective in a photo of flowers, for instance. The restricted depth of field can direct the viewer’s attention exclusively toward the subject.

However, the actual subject matter in the photo must be crystal clear. Settle for nothing less than pristine quality. And don’t rely on sharpening technology (“unsharp masking”) in Photoshop.

In the 1990s I had an associate who would ask me to “Crispy up” an image or say, “Just Photoshop it,” to improve the snapshots she gave me for a newsletter. My belief is, “GIGO” is the rule: “garbage in, garbage out.” Adhering to this maxim gives you the best results.

Dynamic Range

Before digital photography, the rule of thumb was that images from slides were better than images from paper prints. This was because they captured the greatest tonal range from the darkest dark to the lightest light. Paper prints were ok, but the highlights and shadows did not match the depth/intensity of shadows and highlights in transparencies. And the interim steps or gradations from shadows to midtones to highlights available in transparencies were also better than in paper prints.

The general idea is that true black and true white will be the most intense and accurate in the actual scene you photograph (i.e., in real life). This dynamic range will lessen somewhat as you photograph the image. And then it will become an even narrower transition from black to white, or from one dark color to a lighter one, once you offset print or digitally print the image.

Color

Depending on the lighting when you take a photo, sometimes you will get a color cast. This is a color imbalance that shows up in neutral colors (a white sheet of paper in a photo, for example, might have a pinkish cast).

A color cast can also add yellow to a face and make the subject look jaundiced. Be aware of this. Fortunately, you can adjust the image in applications like Photoshop (using an on-screen densitometer) to correct color casts. Moreover, you can do this by reading the numbers (rather than by just relying on the computer monitor). That is, by checking density readings within an image and correcting them, you can successfully remove a color cast whether you can see it on screen or not.

Flaws

For the most part, I’m talking about scratches, which are really only a problem if you’re using paper photo prints or transparencies. In some cases it is possible to remove these blemishes in Photoshop, but it takes a lot of work, and in my experience the results don’t usually warrant the effort.

Flaws can also include patterns in the photo (a checkerboard pattern, for instance, or the pattern in a metal link fence). Sometimes these patterns conflict with halftone screens and cause moires (additional, yet undesirable, patterns). Watch out for these.

Flaws can also include overly large grain (from the silver halide deposits that comprise the images in paper prints and transparencies). I once used a 35mm image for a poster. When I enlarged it from 35mm to 2 feet by 3 feet, the film grain was huge. Fortunately, I still kept my job. But I learned why photographers love 2-1/4”-format handheld cameras and 8” x 10” tripod-mounted cameras. These cameras can maintain crisp detail, a wide range of tones, and rich shadows and clear highlights even when the images are enlarged. And less enlargement is usually required when you start with a large negative (compared to between 700 percent and 1,000 percent enlargement when you start with a 35mm negative).

But flaws can also include extraneous elements in a photo, like a tree that appears to grow out of the subject’s head (which you didn’t see when shooting the photo). For instance, a few days ago I took two photos of an exterior sculpture. In one of them, a car was going by. In the next one, the car was gone. I deleted the one with the car.

Digital Options

In spite of what I said above, Photoshop really is a wonderful application, especially when you start with (technically) good images.

Here are some things to consider:

  1. Make the “histogram” your best friend. This is a graph showing the number of pixels for each level of gray (levels 0 to 255). Ideally, when you open up a histogram in Photoshop you will see a smooth graph from the left to the right, starting with relatively few pixels on the shadow side, a lot in the middle tones, and relatively few on the highlight side. What you don’t want to see in the chart is gaps. These look like missing teeth on a comb. Gaps indicate a total absence of pixels for a specific level of gray. What this means visually is that you will see a stair-stepping of tones (i.e., posterization) in the photo.
  2. Histograms can also come in sets of three or four for full-color work (RGB–red, green, and blue for use on a computer monitor–or CMYK—cyan, magenta, yellow, and black for use in commercial printing). Do some research online, and you’ll find the proper balance for these colors (the relative numbers for each channel using the on-screen densitometer) to minimize or eliminate color casts.
  3. That said, your goal is to have the widest possible dynamic range (dark to light): the most pixel data from the darkest dark to the lightest light with the most picture information in between. A transparency (slide) will give you this result (compared to a paper print), but so will a good image from a high-megapixel digital camera, if you have good quality exterior lighting or highly controlled interior lighting.
  4. If your image is slightly out of focus, you can improve it a bit with unsharp masking, which increases the contrast between adjacent light and dark pixels and thus fools your eye into believing the image has been (to quote my associate above) made more “crispy” in Photoshop.
  5. Proper resolution is vital. I use my cell phone to take photos of my fiancee’s and my autistic art therapy students, but we use the photos almost exclusively for 72dpi online images. They are snapshots, not high-quality images for print production.
  6. That said, when I receive photos for these PIE Blog articles, such as the one above, they come to me in large dimensions at an ultra-high resolution. If I crop in on a small area and enlarge it significantly, I can see the eyelashes on the model’s face or the stitching in her clothes. If I were to save the image as a JPEG at this size and resolution, and uploaded it to the PIE website, it would take forever to load a PIE Blog page. The size of the image (let’s say 10 MB) would choke the software and hardware. However, when I reduce the image from about 36 inches to 10 inches in width at 72dpi, I have adequate resolution for blog readers to see the important parts of the photo–and nothing else. Plus, at this point the photo is about 250 KB rather than 10 MB.
  7. If I wanted to use the same image for a print ad, I would save the image with a resolution of about 266dpi (or double a 133lpi halftone screen) at the final size (reduced from the larger format of approximately 30” x 30”). In this case the size reduction would actually improve the sharpness of the image.

So the gist of this is, use the digital enhancement tools to your advantage. But start out with the highest technical quality and then just tweak the images. Don’t try to save bad photos.

Custom Printing: A Few Tips for Enhancing Your Photos

Sunday, February 21st, 2021

Photo purchased from … www.depositphotos.com

The Problem with Photos

There is a truism, somewhat unflattering in its wording: “garbage in, garbage out.” In commercial printing, whatever you start with in the way of photographic imagery, once you have digitized it (if it starts as a printed photo), opened it in your image editing software, placed the resulting TIFF photo into InDesign, and then handed off the file to the printer for imaging to the press plate, the image has degraded–at least a bit. Printing it on a paper substrate will degrade the image a bit further. Because of this, it is essential that you start with the very best image possible.

What do I mean by degrade? Two things for starters. The range from the darkest tone to the lightest tone in the image will narrow a bit in the journey from camera to offset commercial printing. This is called “tone compression,” the squeezing of the initial range from highlight to shadow.

In addition, the nuances of the visible transitions from highlights to midtones to shadows will be less evident than they were in real life, and less distinct to the eye than they were on the original image (film or digital) once you have printed the photos.

Another way of saying this is that the range and the detail in the subtle transitions from the lightest light to the darkest dark in the image will be minimized as you transition from the camera to the digital file to the custom printing plate to the final job on paper.

How Can You Improve the Quality of Your Printed Photos?

First of all, start with transparencies if at all possible. These have the greatest range from the lightest light to the darkest dark when compared to digital photos or printed photographs. (This is in the process of changing as digital technology improves. So you may want to do some research online for confirmation.)

Transparencies are essentially slides. They come in different sizes depending on the camera you’re using. Most commercial grade cameras bought for regular use are 35mm cameras. (Again, most cameras these days are digital rather than film-based, but back when I was an art director in the 1990s we used 35mm cameras almost exclusively.) Larger film formats were always better in that they captured more detail with less evident film grain (the silver halide crystals that made up the image on cellulose film for analog cameras). Some were 2 1/4” x 2 1/4” square-format cameras. Some cameras supported on tripods for extremely detailed work were 8” x 10” in format, yielding photos with both more and sharper detail in the transitions from one tone to another. Why is this? Because these large-format negatives or transparencies did not need to be enlarged as much as 35mm images for printing. (Even an 8” x 10” print made from a 35mm slide needs to be enlarged approximately 700 percent. A 2 1/4” image requires far less enlargement than a 35mm image, so minor flaws are less visible, but an 8” x 10” original is even better.)

So how does this translate to the digital images to which we have grown accustomed? If more image data affords a broader tonal range and more detail in the various levels from shadows to highlights, then a digital camera that captures more data—with a higher megapixel count—will translate into a better image in your camera and therefore a better image in prepress and final commercial printing.

You may even want to research image formats for digital cameras. From my reading on Camera Raw images, which are sometimes referred to as “digital negatives,” this format seems to be ideal (although it does create very large image files). Camera Raw captures the most picture information digitally, making it similar to working from not only a transparency but a large-format transparency at that.

However, if you do use a film-based camera, and you do choose to work from transparencies, be aware that if you examine transparencies on a light box, they will appear lighter than they will look when printed because they are back-lit. You have the same consideration when you’re evaluating images on a computer screen.

Resolution, Focus, and Depth of Field

One thing I have seen at various commercial printing plants is that if you start with a high enough megapixel image produced with a quality digital SLR (single lens reflex) camera, you can capture enough picture detail to be able to print the image on even grand-format inkjet equipment, large enough to create a mural. If you start with this good an original digital image, clearly you can produce large, crisp-focus images for your books and even posters.

Back in the ‘90s I learned all of this the hard way. I stated with a 35mm transparency and enlarged it for a poster. It was a promotional piece for a nonprofit educational foundation, and I hadn’t yet learned all of what I have noted above. I enlarged the image from 35mm to 18” x 24” poster size, and the film grain in the transparency became acutely visible. It looked like a pointillist painting (dot painting) or perhaps a mezzotint. Ouch.

A comparable flaw these days would be to start with a digital photo with too low an initial resolution and enlarge it (let’s say a 2” x 3” 72dpi image for the internet enlarged to a 4” x 5” format). You wouldn’t see film grain, as you would with a transparency, but you would definitely see pixellation (visible squares of color side by side making up the photo). This is one reason to always select a high-resolution image (300 dpi at the final size you intend to print it).

Flaws are always magnified, particularly if you enlarge the image. So the importance of choosing the highest quality photo pertains to image focus as well. If you start with either a film-based or digital image that is out of focus (or if your depth of field–the area of sharpest focus within a photo–is other than on your primary subject matter), the final printed product will be even more visibly blurred.

So What Can You Do?

Choose the image with the most picture data (digital or film). Make sure it is in crisp focus and the depth of field enhances the subject of the photo. Look at the image on a computer screen, but remember that the photos will appear lighter and the colors more saturated than they will once your commercial printing supplier has offset printed the job on paper.

Another thing you can do is check the images in Photoshop, analyzing their “histograms.” Histograms are vertical bar charts that show the number of pixels at a particular tone level from the darkest dark to the lightest light. You want a smooth curve with no gaps. You also don’t want either the shadow or highlight to be excessive (i.e., you don’t want the histogram chart to spike up at either end of the spectrum with too many completely white or completely black pixels).

Also, look for color casts, but don’t completely trust the accuracy of your (presumably uncalibrated) monitor in an uncontrolled (ambient lighting) environment (perhaps with a window, allowing the sun to change the colors on the screen throughout the day). Do a little research online to determine the proper histogram balance for the color channels (keep the Photoshop file in RGB–red, green, blue–format until you hand off the final, adjusted image to the printer in CMYK format). In this case you’re trying to avoid color imbalances: color casts. These show up on the online color densitometer readings, and on the internet you can find the proper Photoshop (RGB) amounts/percentages to keep all color channels in balance).

The Short Answer

So the best approach to avoid GIGO (garbage in, garbage out) is to give your printer the highest quality images (either film-based transparencies or high-megapixel digital images).

If there are any questions, I would encourage you to hand off the images to the printer for evaluation separately from the final art file submission (and with lots of lead time). A good prepress operator can look for all of the potential pitfalls I have enumerated and give you suggestions before you commit to final job files.

And then always ask for a physical color proof of any critical color work (like a poster or print book cover). If any of the flaws I have mentioned have slipped by, these will appear on a contract-quality color proof, and you can resolve the issues before offset printing your job.

Custom Printing: A Few Random Thoughts on Halftones

Tuesday, March 24th, 2020

With the Coronavirus threat upon us, I have had extra time recently, so I have taken this time to brush up on my knowledge of commercial printing. I thought I’d start by reviewing my textbooks on color prepress and custom printing.

In this light, I chose the subject of halftones. I thought my findings might be of interest to you.

Why Use Halftones?

Offset printing is a binary process. Either you print ink in a particular place on your press sheet, or you print nothing. You can’t print a continuous tone image (either color or black and white) where black tones transition into gray tones and finally into white.

So how do you get images to look right on a commercial printing press?

Long before computer prepress and scanning devices existed, it was discovered that if you photographed a continuous tone photo through a glass sheet covered with a matrix of “cells” (like small, separate windows), this process would yield an image composed of dots. Depending on the lightness or darkness of the area represented, you could have a light area comprising many small dots or a dark area comprising many large dots.

Due to the regular position of the little “windows” on the halftone screen (the same number of lines of halftone dots, all lined up across and up and down on the screen), there was a constant and finite number of halftone dots. They were just larger or smaller in size, depending on whether they were in dark or light areas.

The number of halftone dots per linear inch was called the screen ruling. For reproducing images on thin, porous paper like newsprint, commercial printing suppliers would use coarse screens (85 lines per inch, for example). For coated paper, printers would use 133lpi or 150lpi screens (or even much higher rulings).

As the printing and prepress processes were computerized in the ’80s and ’90s, all of the above information pretty much continued to be true (albeit on a digital rather than analog level).

On the plus side, the human eye is very forgiving, and from a normal reading distance, the dots in the finer halftone screens (133lpi or 150lpi) cannot be seen easily, whereas the dots of the coarser halftone screens (85lpi) printed in newspapers are usually visible. Unfortunately, trying to print finer line screens on newsprint yields muddy images, since the absorbent nature of newsprint makes the halftone dots spread. Ink goes into the paper fibers and travels. Images look horrible. So you really do need the coarse (lower-number) halftone screens for cheaper paper.

Fortunately, coated printing paper allows the ink to dry on the surface of the press sheet (rather than seeping into the paper fibers), so the halftone dots can be smaller without spreading (they’re called “hard halftone dots”). But these harder-surfaced, coated press sheets are more expensive than lower-grade papers like newsprint, so high quality photos, in which you can barely see (or not see at all) the halftone dots, usually wind up in higher-end publications.

To keep you apprised of the printer’s lingo, this growth of printing dots is called “dot gain.” One way commercial printing vendors compensate for this is to print less ink by intentionally lightening the halftone screens (by slightly reducing the halftone dot sizes) so the printed output will be correct after the inevitable dot gain.

What About Color Images?

Back in the day, printers separated 4-color images into four distinct negatives, one for each of the commercial printing process colors: cyan, magenta, yellow, and black. Then the printers produced printing plates from these negatives. All of this was an analog, photographic process. Now, all of this is achieved digitally with scanners and computers, but the concept is the same. An image is scanned and then separated into the four process colors. These are then printed not to film but directly to custom printing plates, one for each color.

But here’s the trick. Each of these four separated images really is just one halftone, just like the halftone described above that is used for black and white images. The difference is that the four halftones for color printing are rotated at slightly different angles to one another. For example, one option is 15 degrees (cyan), 45 degrees (black), 75 degrees (magenta), and 90 degrees (yellow). Yellow dots are less visible, so they can be set closer to the angles of the other screens (15 degrees in this case). The best angle for viewing is 45 degrees (so it’s used here for the black plate).

Because of this distribution of the four halftone angles (just the halftone angles, not the printing plates themselves), once the image is printed, you will see a circular “rosette” pattern in the images if you use a 12-power printer’s loupe to magnify areas of the photos. These rosettes are the visual indication that the halftone screens have been rotated. And they appear larger or smaller depending on the size of the halftone dots in a particular area.

Another way to say this is that the rosettes are more visible in areas printed with more ink (dark areas) and less visible in areas that take less ink (lighter areas).

Dot Shape

These halftone dots can be a number of shapes, including round, square, and elliptical. Round dots are the norm (from very small to very large depending on the density of ink in a particular area). Elliptical dots, on the other hand, are very good for skin tones because as they grow in size (from small at the quarter-tones to larger at the three-quarter tones), the longer dimensions of the elliptical dots eventually touch each other, and this makes for smoother gradations in flesh tones.

(Square dots are good for detail work with lots of straight lines and angles.)

I’ll say this again because it’s very complex. But the overall concept is what’s important. The way elliptical dots touch at the long ends as they get larger (to allow for increased ink distribution) makes for smoother transitions in the tones of a human face. If you’re printing high-end glamour photos for Chanel, this is useful information indeed.

Amplitude-Modulated vs. Frequency-Modulated Screening

All of what I have been explaining is called “amplitude-modulated screening.” This just means the dots are all on a fixed grid (i.e., the same number of rows and columns of halftone dots in a 150lpi screen, for instance). They are just larger or smaller depending on the ink density.

In contrast, you can now use “frequency-modulated screening” or even a hybrid that blends both AM and FM screening. Frequency-modulated halftone screens are made up of equal-sized dots (minuscule ones). They’re all the same size, but where there’s a lot of color, there are a lot of small dots.

If you look closely at the output of an inkjet printer, you’ll see exactly this kind of pattern. In contrast, if you look at the output of a laser printer, you’ll see some version of amplitude-modulated halftone screening. Laser printers may not use the exact same screening angles as used for offset commercial printing. They may not even produce the same rosette patterns. But they are based on similar mathematical algorithms as those used for offset printing.

TAC, UCR, and GCR

First, here’s the wording referenced by the acronyms above:

TAC=Total Area Coverage
UCR=Undercolor Removal
GCR=Grey Component Replacement

TAC means total area coverage. If you print 100 percent coverage of all four colors (cyan, magenta, yellow, and black) in one place on a press sheet (a high-density neutral area of a photograph), you could conceivably be printing 400 percent (100 percent x 4 colors) total ink coverage. Unfortunately, too much ink makes the offset lithographic process break down, and the paper also can’t handle that much ink (it gets too wet and comes apart). The ideal overall target might be 270 percent to 300 percent for all four colors, depending on your printer, the press, the paper, etc.

UCR means Undercolor Removal. This and GCR or Grey Component Replacement are ways to replace the cyan, magenta, and yellow in a photographic image with black. When you do this successfully, you achieve two things:

  1. You can use less ink. This reduces materials costs and ensures that there’s never too much ink anywhere on a press sheet (see above for the results of printing too much ink).
  2. When you create neutrals, or even gray areas, with cyan, magenta, and yellow, any misregister of the printing plates will cause color shifts and color casts. Replacing some of these hues with a percentage of black will minimize these color shifts significantly.

What You Can Learn From All of This

If your head hurts from all of this information, I apologize. That said, it doesn’t hurt to begin to understand the nuances of prepress and presswork. It will help you understand why you prepare design files for press the way you do. It will also help you make good choices regarding printing paper.

There are a lot of good textbooks out there that describe these technologies and their challenges. However, it’s even easier to find little booklets produced by custom printing suppliers and paper companies that give you this information in a condensed form (only what you need). The more you know, the better able you will be to discuss your commercial printing needs with both your sales rep and the pressmen actually printing your job.

Custom Printing: Thoughts on Designing with Photos

Monday, March 2nd, 2020

I was reminded this week while teaching an art therapy class that the principles of design are the same for fine arts and graphic design. We were making clocks by building up paper collages over Nordstrom shoe boxes with clock motors attached to the box tops.

As source material for the collages, my fiancee had collected and silhouetted photos of the autistic members, and had also collected large sepia images from an oversized Italian fashion magazine as well as color photos and drawings from an advertising promotion print book.

What started as a fine arts project began to gradually expand into a graphic design project, as the autistic members and their parents and aides wrapped the images around the boxes, in various sizes, at various angles, and with various photo croppings. Some images were tightly cropped, with parts of models’ faces wrapped around the box corners or cut off entirely. In some cases the members even cut out words from the magazines and pasted them down, or glued Scrabble letters onto the clock shoe-boxes to spell words.

I observed, and I thought, and then I explained the following principles to help them with their artwork:.

Photo Cropping

Images can have a lot of space around the subject matter (such as a person’s face), or they can be “severely” cropped. That is, you can focus intently on one aspect of the face, such as the eyes, by cropping away everything else.

This concept is immediately transferable to publication design as well. (In your own work, whether you’re designing a brochure, logo, or print book cover, try different approaches to photos. Decide what you want the image to “say.” What’s the message you want to convey, and how can you most effectively make this statement by highlighting certain elements of the photo? If you’re doing this on a computer with an image editing application and a page design program, your ability to play with different approaches is enhanced (compared to my fiancee’s and my students’ approach with scissors and glue).

I also encouraged the members to run the photos off the edge of the boxes, and perhaps from one side of the shoe box onto an adjacent side.

This is relevant to publication design as well. In graphic design it’s called bleeding an image off the page, and what it does artistically is give the impression that the magazine, brochure, or print book page is larger and more opulent than if the photo did not bleed off the page (if the image is just surrounded by the white text page). The bleed gives the illusion that the image is much larger and that it actually extends off the page.

Photo Contrast

Much of what creates interest in either a work of fine art or a page in a graphic design project is the contrast between (or among) images. This contrast can be achieved in many ways:

  1. Contrast of size
  2. Contrast of color
  3. Contrast of content (simple vs. busy, for instance)
  4. Contrast in the edge treatment of the images (straight edges, torn edges, or shadows behind the images)

All of these were relevant in the creation of the autistic members’ clock collages on the shoe boxes, but they are also equally relevant in the design of a print book, brochure, poster, etc.

I suggested that the students start by choosing a larger image (perhaps a sepia or black and white one) for the background of the front of the clocks. The clock hands and numbers would eventually be placed over this large, dominant image. I suggested that they then choose smaller images (including their own photos which my fiancee had silhouetted) and other photos to position in various places over the larger photo (i.e., smaller shapes positioned over one unifying, larger shape).

The autistic members saw just how the smaller photos laid over the larger photos created a contrast in size, actually making the larger photos seem larger and the smaller photos seem smaller. A silhouette of a person looked small when superimposed over a sepia toned background. This created a sense of interest, balance, and movement. That’s what contrast does in a piece of fine art, but it’s also what it does in a graphic design piece like a print book cover.

I noted that the sepia toned photos were “desaturated.” They lacked intense color. Therefore, the members could create contrast, interest, and movement with small color photos laid over the larger, less intense images. The intense hues of the smaller color images would catch the viewer’s eye first.

The same is true for designing a poster or any other graphic design piece.

Now for contrast in content. One of the members found a color photo of a hand and placed it over a much larger sepia toned photo that included a number of people. The difference between the busy background photo and the simple elegance of the hand photo made for an interesting contrast.

Finally, I encouraged the members to tear the photos. I noted that this created random, irregular photo edges that might be interesting when laid over straight-edged photos—again, a contrast between the simple and regular and the varied and jagged.

Moreover, I told the members, parents, and aides about line direction: vertical lines imply stability; horizontal lines suggest peace and tranquility; and diagonal lines give a sense of movement and energy to an artistic piece.

Again, the same is true for graphic design.

Now contrast by itself is just a trick. I strongly encouraged the members to use the contrast to set up an intentional direction of eye movement through and across the various sides of their clock collages, using such attributes as strong color or interesting photo cropping to draw the eye to certain elements of the design first, second, third, and so forth.

What You Can Learn from This Case Study

The first thing to learn is that successful graphic design and successful fine art are based on similar (or even the same) principles. You can learn a lot by going to the art museum or studying fine art print books along with your design textbooks. In fact, you might want to study the following artists: Piet Mondrian, Toulouse Lautrec, and Andy Warhol, all of whom pursued careers in both graphic design and fine art. If you keep an open mind, you’ll learn a lot.

Another thing to learn is that contrast elicits interest in a piece of fine art or a graphic design. You can contrast size, color, edge treatment, or the amount of activity in photos. But for this not to become a trick of the eye, it’s important to consider the message you’re conveying and how you want the reader’s eye to travel through the fine art piece, poster, brochure, print book page spread, or whatever. Ask yourself the following. How can your treatment of the images reinforce the statement you’re making?

Another thing to learn is that the more you look, the more you will see. If you like a billboard you see while driving, ask yourself why. What is the message it conveys, and how do the various graphic elements reinforce this message? If you like a poster, brochure, or print book page spread, ask yourself the same questions.

Also, since our world is becoming increasingly visual, with YouTube apparently surpassing Google as the primary search engine, consider the use of photos online, in commercial printing, and even in photo collage. (By the way, the collage work our autistic students were doing is called photo compositing in the graphic design world. The main difference is that graphic designers do the compositing in Photoshop on a computer rather than by hand with magazine photos, scissors, and glue.)

Book Printing: A Few Thoughts on Image Preparation

Saturday, April 22nd, 2017

In spite of the promotional literature implying the ease with which one can seamlessly use Photoshop, InDesign, and Illustrator, there really is a lot to learn. And when you’re using these programs together to prepare large book printing jobs for either offset printing or digital printing, the learning curve is even steeper.

That said, I have three book printing jobs I’m brokering at the moment. They are all close to 8.5” x 11” in format, and their press runs range from 500 copies to 11,000 copies (perfect bound and case bound).

In this particular case, the physical properties of the print books are less important than the preparation of the art files, or, more specifically, the preparation of the images to be placed in the InDesign files.

My “DIY” (Do-It-Yourself) Client

One of my clients has written and designed her book and then has prepared all pages in InDesign. She may also have taken the photographs. But she is somewhat new to Photoshop. To her the images are more important than the words. This is a cookbook, and she wants the images to take the lead.

From a commercial printing standpoint, because of this orientation toward the images, I have suggested that my client select a gloss coated printing stock. But for the custom printing paper to showcase the nuances of the images, the photographs must be correctly prepared prior to being placed in the InDesign file.

One of the things I learned, purely by accident during a discussion with my client, was that she had kept the photos in RGB JPEG format as they had been initially shot. Since she knew she wanted the text of the book (both words and images) to be printed in black ink only, she had merely desaturated the photos in Photoshop (i.e., removed their color but kept them in RGB format).

This had made perfect sense to her (and was a logical approach), but it was not what the offset printer would need in order to produce her book. So I gave my client the following suggestions. I think these would benefit a number of new designers (and designers who had come of age with traditional paste-up and are only now making the shift to computerized design and prepress):

My Suggestions to My Client

  1. I told my client she needed to convert all photos from RGB JPEGs to Grayscale TIFFs. Some printers can work with JPEGs, but it’s safest to use TIFFs because all printers will accept these.
  2. If my client had continued to use RGB, the printer would have needed to convert the files himself to CMYK (from Red/Green/Blue, which is used for video monitors, to Cyan/Magenta/Yellow/Black, which is used for ink or toner applied to paper). These color spaces are not the same. A color image mode change from one color space to another can cause color shifts.
  3. In my client’s case, if she had kept her files in the CMYK mode, the offset printer would have prepared printing plates for all four colors. In essence, even if the computer monitor had given the impression that her images were black and white, they would have been created with all four process colors. Printing the interior text pages of the book in full color would have cost multiple thousands of dollars more than printing a black-only text block. Since this would not have been acceptable, all of her work would have needed to be redone after the first proof, and then a second proof would have been required, further adding to the cost. So understanding how to use Photoshop to change the color mode from RGB to Grayscale was important for my client (as was doing this in a way that optimized the tonal range of the photos: i.e., the detail in highlights, midtones, and shadows).
  4. I suggested that my client look online for a tutorial on preparing black and white images for commercial printing. I have seen many such tutorials. They are succinct and extremely useful. They discuss everything from image resolution to changing color modes, to optimizing highlights and shadows for offset printing.
  5. I encouraged my client to make decisions regarding highlights and shadows based on “numbers” in the Photoshop dialog boxes (the “Info” palette, for instance), rather than by looking at the computer monitor. I noted that backlit images on a computer screen will look brighter than the same image files printed with ink or toner on paper. Learning to interpret the “numbers” (the numerical values for the colors and tonal range) would minimize error.
  6. I suggested that my client prepare a few pages of text and photos and then have the printer run a digital proof of just those pages as an initial test. If they looked too dark or too light, that feedback would help her in preparing the remainder of the book. I suggested that she approach the proofing process as an investment, not an expense.
  7. I spoke with the printer about providing his prepress department’s checklist for producing optimal, press-ready PDFs, so that once my client had received the initial few test pages and applied what she had learned to the remainder of the book, she would know how to convert her InDesign file into the best possible PDF file. He agreed. (Many printers already have such a PDF creation checklist. The reason this is useful is that different printers have different preferences for the numerous options available in creating a print-ready PDF file.)
  8. I encouraged my client to request the following proofs: the 3- to 5-page initial test file (plus any revisions needed); a high-resolution digital proof of all photos ganged up onto approximately 100 pages; the overall digital proof of the book (a “contract” quality, digital cover proof such as a Spectrum or Epson, plus laser proofs of all text pages); and folded and gathered book signatures handed off following printing but before binding the book. Overall, this would let my client see every stage of the process. Since this print book is her pride and joy, her “baby,” these multiple proofing stages will help ensure success.

What You Can Learn From This Case Study

You can apply most of the suggestions I gave my client to your own work.

  1. Find out how your printer needs you to prepare images. Check online for short tutorials that teach you how to prepare Photoshop images for offset printing. They will give you a limited number of steps to follow to ensure your success with offset printed images.
  2. Consider requesting any or all of the proofs I have suggested. It may cost a little more, but it will help you identify problems before the book has been printed. At minimum, consider a high-res proof of the cover and “for position” proofs of the text. If you have images or tint screens, consider requesting high-res proofs of these pages. The jargon to use is “contract proofs.” These serve as a contract between you and the printer: once you have approved the way they look, he has to match these proofs exactly.
  3. Ask for your printer’s PDF-creation guidance sheet. Don’t assume one printer’s PDF-creation guide is the same as another’s.

Custom Printing: Thoughts on Using Photos Effectively

Saturday, January 17th, 2015

I found a very simple and accessible book on design at a thrift store recently. It was written by Robin Williams and John Tollett, and it’s called Design Workshop.

If you are a custom printing designer, I would encourage you to make it a regular practice to analyze printed products like brochures and billboards, as well as design books like Design Workshop, in order to maintain and even improve your design skills. Stephen R. Covey (business self-help guru) calls this “sharpening the saw,” and I’ve always been a strong believer in continuously practicing the fundamentals of the craft of commercial printing and design.

Improving Your Photos

I recently reviewed some photos for a print book with a brokering client, and a number of Williams’ and Tollett’s suggestions would have improved the photos. They will be printed on matte coated stock in an eight-page photo signature bound into the middle of the print book. Some of the photos have more of a “snapshot” look. That is, they look amateurish. Fortunately, a lot of Williams’ and Tollett’s suggestions can be applied to these snapshots to turn them into more professional-looking “photographs.”

The section of Design Workshop to which I refer addresses the creative and effective use of photographic images. Here is a short list of the book’s suggestions:

Be Conscious of the Background

Consider where the subject of the photo is placed relative to the background. If a stovepipe in the background appears to be growing out of the subject’s head (i.e., is directly behind her or him), move your vantage point, as the photographer, to the left or right to remedy this. Although this sounds like common sense, it’s very easy, when you’re taking a photo, to only think about the person you’re photographing and to forget the background.

(Design Workshop does not address this directly, but if you have been provided with photos and the only photo you have to work with has a stovepipe or other item behind the subject, consider silhouetting the image.)

Avoid Clutter

Consider the clutter in the background when you’re taking a photo. Keep it simple. Also, if distracting elements like furniture extend into the photo from outside the “picture frame,” move them or change your vantage point for the photo. Even something like a window in the photo can be distracting. The bright sunlight coming into the room can take your viewer’s or reader’s attention away from the main subject. In short, always consider photo composition.

(Design Workshop does not address this directly, but if you use Photoshop’s cropping tool creatively, you can improve images if you only have photos with cluttered backgrounds. Severely cropping into any of the distracting elements in the photos can minimize their impact.)

Consider How the Viewer’s Eye Moves Around the Photo

Think about the reader’s eye movement through a photo. In Design Workshop, Williams and Tollett include a photo of a series of motorcycles riding away from the viewer through what appears to be mud. You cannot see any faces, but the photo is interesting because your eye moves from the largest motorcycle in the foreground (front right), through the middle ground (a smaller motorcycle, due to its distance from the viewer) to the background at the upper left of the image (the smallest motorcycle, since it’s the farthest away from the viewer). In the distance, you can see a line of trees. The photo is interesting because of its great depth of field, from the foreground images to those in the background, and because of the way the photographer leads the viewer’s eye through the image.

Shoot from Unique Vantage Points

Williams and Tollett also encourage you to take photos from unique vantage points. They include a photo of people around a table eating a meal. In this case the photographer shot the image from above, presumably from a balcony. What makes this image work is that it flouts expectations. You expect an image of a dinner to be shot from the same level as the diners. Shooting it from above provides more of a focus on the interactions among the diners and deemphasizes the individual people at the table. It becomes more of a design, or pattern. Also, the angle of the table (diagonal to the picture plane) makes for a more dynamic composition.

Crop Photos Wisely

Design Workshop includes two variations of a photo of a couple in a chair or loveseat looking at a candle. It’s very romantic, but the original photo is also cluttered. By cropping severely into the image (just above the man’s eyes, leaving just a little of his forehead) and leaving the candle just inside the left-most crop of the image, the designer eliminates the clutter while focusing on the two faces and the candle. This is a dynamic balance (and a good way to remedy a busy photograph).

What You Can Learn from Williams and Tollett’s Design Workshop

Photos add drama and personality to a layout for a commercial printing job. Learn to analyze them critically, and look for those specific attributes that will make the images—and the layout of your print book, brochure, or large format print—both striking and memorable.

Custom Printing: Creating Four-Color B/W Images

Friday, May 23rd, 2014

At first glance, the concept of four-color black and white images would appear contradictory. After all, either you print halftone images in black ink only, or you print them in full color (i.e., cyan, magenta, yellow, and black ink). Or do you?

How about duotones? When you create a duotone, you usually print an image in black and a second color, or you print the image in two PMS colors. When you do this, you create two halftone images with different tone curves (in Photoshop). That is, you focus on a certain portion of the halftone (let’s say midtones and highlights, or quarter-tones and three-quarter-tones. You do this because of the imperfections of printing. Using one custom printing ink and one halftone screen cannot capture the full range of tones from the darkest dark to the lightest light. Something suffers. But each time you add a color (as with a duotone), you can extend the range of tones in the composite halftone image. (This is called increasing the “dynamic range” of the image.)

But that’s a duotone. What about a four-color black and white image?

The same goes for four-color black and white images. If you use cyan, magenta, yellow, and black together, you can (for the most part) capture the full range of color in an image. But if you want an image that stands out because of its simplicity (and a rich, black and white image will definitely stand out in a world of full-color imagery), you can adjust the percentages of the process colors in the halftone to simulate an achromatic (no-color) image.

And given the ability to use each of the process color screens to enhance a specific portion of the tone curve (highlights, quarter-tones, midtones, three-quarter-tones, shadows), you can end up with a deep, rich photograph impossible to create with a single black ink. Or, more precisely, you can hold detail and levels of tonal transition in the deepest shadows, the midtones, and the highlights simultaneously.

But Problems May Arise

As with any truly wonderful artistic technique, this one has dangers as well, namely color shifts or color casts. The success of a four-color black and white image rests on the ability of your commercial printing vendor to hold a neutral gray balance in the image. That is, the image cannot have a color cast, or it will no longer have the characteristic look of a black and white photo.

On press, color casts can occur for a number of reasons. Among these are dot gain. If the halftone dots spread on the press sheet, then the precise balance of the four process colors that yields a true achromatic black will be lost, and the image may tend toward a cyan, yellow, or magenta look.

In fact, it is because of the tendency of neutral grays to shift toward a color tone that such processes as UCR (under color removal) and GCR (gray component replacement) are used to replace a cyan, magenta, and yellow on press with black ink. This stabilizes the overall image color and avoids color casts. In the case of a four-color black and white image, we’re consciously choosing to do the opposite of UCR and GCR. So it’s risky.

In-Line Color Conflicts

Another cause of color casts (in addition to dot gain in one of the process colors, or over or under inking resulting in a color imbalance) is an “in-line conflict.”

An in-line color conflict often occurs in a magazine press signature in which heavy-ink-coverage advertisements, solid colors, and lighter areas of type are distributed across one side of one press signature. To understand this, picture a 16-page signature with four 8.5” x 11” pages across the top of the sheet and four more pages immediately below. On the back there will be eight more pages making a total of 16. This is a traditional 16-page signature.

The individual press sheet travels through the press with the top four pages of the signature going through the inking units first, followed by the four pages immediately beneath them on the flat press sheet. If images on the top four pages use a large amount of a particular process color, it is entirely possible that the pages immediately underneath them (or “in-line” with them) on the 8-page side of the press sheet may be adversely affected by that larger amount of color.

For instance, if a large image on the top left page of the signature requires a large amount of magenta ink, the magazine page immediately below it (i.e., in-line with it) may have a magenta cast as well. If you’re custom printing a four-color black and white image on that particular magazine page within the press form, it may shift from a deep rich black to a rose-tinted warm black. This may be unacceptable.

Fortunately, your commercial printing supplier may suggest putting the four-color black and white image on a different page within the press signature, one that would be less adversely affected by such an “in-line conflict.”

To achieve success with four-color black and white images, the best thing to learn from this discussion is not to avoid four-color black and white images but to involve your custom printing vendor early in the process. Describe your goals. Make sure your printer has done high-end work like this before. And consider attending a press inspection so you will not be unhappily surprised with the final product. After all, on a press inspection, you can identify a color cast and ask the pressman to fix it.

Designing & Printing: Five Tips for Designing with Images

Friday, September 20th, 2013

Here are a few ideas you may want to consider when designing newsletters, directories, annual reports, or other print products containing multiple images.

Standardize Portraits in Directories, Annual Reports, and Newsletters

I just received a sample printed directory and noticed something odd about the photos. They had been shot by different photographers, so the backgrounds were different, the lighting was not the same, and the cropping of the photos left different sized heads within the standardized 1” x 1.5” image frames.

In general, I would say that this is distracting. One of the qualities of good graphic design is standardization: of type, of the design grid, and of images.

Therefore, it is wise to either shoot (or acquire) images in which the backgrounds contain similar colors and are nondescript. After all, the goal is to focus your reader’s attention on the foreground of the photos rather than the background. In addition, it is wise to crop your images to keep the heads (and hands, or other similar elements of the photos) proportional to one another.

The human eye is lightning fast in recognizing patterns. Image-heavy printed documents such as annual reports, directories, and such, will often include photos with similar compositions. Newsletters may also include similar photos, such as images of people giving or receiving awards.

The reader’s eye will see both the pattern within multiple photos and a break in the pattern if your images differ in composition. This is often a challenge to remedy, obviously, since you can’t always control the source from which the images come. At a time like this, sometimes all you can do is be aware of the problem, strive for uniformity at least in the cropping and size of the people, and move on.

At this point you may also want to check for color casts in photos. If all of the photos have predominantly blue backgrounds, and one of your sources submitted a head shot with a reddish cast in the background, this will stand out and look odd. Therefore, you may want to adjust the color in Photoshop.

Scan Signatures at Sufficient Resolution

Images include more than just photos. They also include line art. While you would scan a photo at twice the halftone line screen the custom printing supplier will use (300 dpi, for example, for a 150-line halftone screen), you would need much higher resolution for line art.

For instance, if your newsletter or annual report will include a letter from the CEO, you will probably need to scan his or her signature. It is wise to scan the image at 1000 or 1200 dpi to minimize the jagged edges that result from scanning line art. (That is, you want the image dots that make up the signature to be as small as possible.) I’d also scan the image as line art within the “bitmap” mode in Photoshop rather than within the “grayscale” or color modes (RGB or CMYK). A black-only image that you colorize within the page layout software (InDesign) will have crisper edges than one you have scanned in color or grayscale.

Be Conscious of the Color Space of Your Images

You will probably scan directly into RGB mode. This is appropriate for computer screens (Internet design, multimedia, etc.) but not for offset or digital custom printing. So remember to change the color space of each image from RGB to CMYK before handing off the job to the printer. It’s easy to forget. So use the “Links” panel in InDesign, highlight each image in the list, and check the bottom of the window to confirm the correct “color space.”

Save Images As TIFFs for Offset and Digital Custom Printing

If you receive a digital scan as a JPEG, that’s fine. However, once you have opened the files and adjusted the images for your commercial printing vendor, save the images as TIFFs. If you need to compress them to make the files smaller, specify LZW compression. JPEG is a “lossy” compression algorithm. Each time you save an image to the JPEG file format, you delete digital information and therefore reduce the quality of the image to make the file smaller. In contrast, LZW compression is a “lossless” algorithm. It does not damage the photos.

Avoid Both Blur and Excessive Sharpening in Photos

If your images are blurry, that’s a problem. However, if you use a sharpening tool in Photoshop such as “unsharp mask,” and you do this to excess, you may add halos to portions of your images. Too sharp is just as bad as not sharp enough. Unsharp masking increases the contrast between adjacent tones, and this fools the eye into seeing a sharper image. But taken to an extreme, this makes the image look unnatural.

Commercial Printing: Optimizing Photos in Photoshop

Tuesday, January 29th, 2013

I’ve been doing some consulting recently, helping a designer prepare photographs for a personal history print book. The photos are quite old, from World War II. This is the designer’s first exposure to photo preparation. He is changing careers. Although he is learning the techniques rapidly, this will be a trial by fire due to the work needed. My task is to teach him what he needs to know and oversee the photo manipulation.

The Process of Optimizing Photos

I have suggested that the designer (let’s call him Bill) follow a protocol to make photo preparation more routine. This should speed up the process, and make it more intuitive. After all, there are a lot of photographs to process.

I suggested the following workflow.

  1. Change color space from “RGB” to “Grayscale.”
  2. Scale and crop photo to final reproduction dimensions.
  3. Ensure that photo is 300 dpi at final size.
  4. Use cloning tool to correct small imperfections, such as dust spots.
  5. Adjust levels or curves to ensure a wide range of tones.
  6. Lighten the photo slightly to compensate for dot gain.
  7. Use unsharp masking in the filters menu to sharpen the image.

I read once that this series of steps would correct most problems with almost 95 percent of the photos a designer will need to manipulate.

I would add one further approach to the photos, given the massive number for this particular print book. I call it “triage,” from the medical term referencing the decisions for treatment based on the severity of the wound. If you are preparing photos for a brochure, this will be less important, since you will probably have only a handful to correct. But you have 50, 100, or more photos, it will be important to decide whether an individual photo is worth correcting. If it has major flaws (not enough tones from the lightest lights to the darkest darks, tears or scratches across faces or other detailed portions of the image, and so forth), you will need to invest a huge amount of time in a single photo. If you are batch processing 50 photos, you can’t necessarily afford to get stuck on one photo. You need to ask yourself whether it’s worth fixing the photo or whether it is a better use of your time to find another.

So to expand a bit on the photo processing list, here are some thoughts:

Color Space

Normally you will receive digitally scanned photos in RGB mode. However, if you will hand them off to a digital or offset commercial printing vendor, you will need to convert the images to CMYK (4-color process). To allow for the best reproduction, it’s best to keep images in RGB mode until the end of the process and then convert them to CMYK. On the other hand, if you will be producing black-only halftones (which is what my client is producing), change the color space from RGB to Grayscale first. You’ll get a clearer view of what you’re doing, since images can look very different in black and white than in color. The grayscale command is in the image menu under “mode.”

Scale and Crop

It’s best to come at least close to the final size and cropping when you place a Photoshop TIFF image in InDesign. And remember to avoid (like the plague) increasing the size of an image.

Resolution

Assume that you will need twice the custom printing vendor’s halftone line screen’s worth of pixel information in a photo. If your printer is using a 150 lpi line screen for halftones, make sure your photos will be at 300 dpi resolution (at the final printed size). Otherwise pixels may be visible.

Cloning

Use the clone tool in the vertical menu on the left side of the Photoshop pasteboard. It’s called the “clone stamp tool,” and it is about halfway down the series of tools. On the top horizontal menu, look for “opacity.” If you’re worried about damaging the photo, you can work gradually to correct flaws by reducing the opacity of this tool. Option click on a spot you want to use as source material to cover a flaw. Then point the cursor at the destination (the flaw) and click and draw. You will be drawing with the pixels you had selected, effectively covering the “destination” area with the “source” pixels.

Levels and Curves

Books could be written about these tools. Research them on the Internet. Your goal should be to give an image a wide selection of tones from black (if you’re working in grayscale, like my consulting client) through the dark grays, mid-tone grays, light grays, and white. Avoid abrupt changes in tone (they appear as spikes in the “histogram,” a graph that shows how many pixels of each grayscale tone a photo contains).

Lighten for Dot Gain

Ink spreads on paper as it flows into the fibers. In addition, your LCD monitor will make photos appear lighter than they will print. So compensate a bit by lightening your photos prior to handing off your job to your custom printing supplier. If you have any concerns, send sample photos to your printer and ask for advice.

Unsharp Masking

Unsharp masking (found in the “filter” menu under “sharpen”) makes images appear sharper (less blurry) by accentuating the tonal difference between light and dark pixels. Too much adds artifacts and halos. This looks painfully bad. You have three variables for unsharp masking: amount, radius, and threshold. Check online for starting values (i.e., amount: 75, radius: 1, and threshold: 10, as noted in one online tutorial by Simon Mackie for “soft subjects”). Experiment. If you see graininess or halos, you’ve gone too far, so back off.

Then save the image as a TIFF file.

Archives

Recent Posts

Categories


Read and subscribe to our newsletter!


Printing Services include all print categories listed below & more!
4-color Catalogs
Affordable Brochures: Pricing
Affordable Flyers
Book Binding Types and Printing Services
Book Print Services
Booklet, Catalog, Window Envelopes
Brochures: Promotional, Marketing
Bumper Stickers
Business Cards
Business Stationery and Envelopes
Catalog Printers
Cheap Brochures
Color, B&W Catalogs
Color Brochure Printers
Color Postcards
Commercial Book Printers
Commercial Catalog Printing
Custom Decals
Custom Labels
Custom Posters Printers
Custom Stickers, Product Labels
Custom T-shirt Prices
Decals, Labels, Stickers: Vinyl, Clear
Digital, On-Demand Books Prices
Digital Poster, Large Format Prints
Discount Brochures, Flyers Vendors
Envelope Printers, Manufacturers
Label, Sticker, Decal Companies
Letterhead, Stationary, Stationery
Magazine Publication Quotes
Monthly Newsletter Pricing
Newsletter, Flyer Printers
Newspaper Printing, Tabloid Printers
Online Book Price Quotes
Paperback Book Printers
Postcard Printers
Post Card Mailing Service
Postcards, Rackcards
Postcard Printers & Mailing Services
Post Card Direct Mail Service
Poster, Large Format Projects
Posters (Maps, Events, Conferences)
Print Custom TShirts
Screen Print Cards, Shirts
Shortrun Book Printers
Tabloid, Newsprint, Newspapers
T-shirts: Custom Printed Shirts
Tshirt Screen Printers
Printing Industry Exchange, LLC, P.O. Box 394, Bluffton, SC 29910
©2019 Printing Industry Exchange, LLC - All rights reserved