Workflow for getting the color right

[john_sarsgard1]

I'm a pretty experienced wet darkroom B&W printer. I know how (for me) to get density and contrast right,

and am OK at dodging and burning in, etc. I have never been a wet color printer, and know little about it.

I want to learn color printing digitally. I have been working at this for a while now, and know quite a bit of

photoshop, and am at the point that I don't think I'll have to learn too many more PS functions.

 

Where I need work is where digital printing is most like wet color printing. I need a good workflow for

recognizing what is wrong with color and getting it right. I need to learn to eliminate color casts, manage

saturation, hue, color balance, etc. Most of what I've read seems to assume I know nothing, and doesn't

add much, or assumes I already know this stuff.

 

Do you have a favorite book, tutorial, or class that you think might help? Many thanks.

[jtk]

Miserable digital color prints made by people with incredible amounts of the latest technology seem common (one of the reasons for the taste for wild colors)...and not surprisingly, those people can't tell the difference between 10 Cyan and 5 Blue. Acquired personal visual skills with color still count, just as with B&W. Lacking practiced visual skills, one becomes a slave to gizmos. That was always true with wet darkrooms, as well. Practice makes perfect. Books won't take you where you want to go, but they're helpful sometimes. I think you'd be better off with musty old color darkroom books, such as Kodak's.

[Spearhead]

No rants from me, just a suggestion to look at Martin Evening's book, do calibration properly for your monitor, and then make sure you understand the printer operation. You could get some cc filters and try using them. I've found a good idea of knowing what you want and combining Photoshop techniques with proper calibration and driver setup is all you need.

[patricklavoie]

1_start by using a calibration device to calibrate your screen

 

2_read READ WORLD COLOR MANAGEMENT

 

3_use the ICC profile when you print

 

4_Print and ask people you trust who know color to give you some info about your prints.

 

5_Like the tradional darkroom, experience will help over time.

[robert_martin5]

What type images are you working with - JPG, TIF, RAW, 8 bit, 16 bit, ditital camera images, scanned images?

 

You have more freedom to make adjustments if you work with digital camera RAW images. If JPG or TIF, a first pass has already been made by the camera and you have less freedom to make adjustments. JPG images can only have 8 bits and have been compressed to save space, so they are further restricted. JPG compression is a lossy compression, so data is thrown away to reduce file size each time you save a JPG image.

 

I work with camera RAW images and its easy to get color correct if you have a reference shot with a netural color (gray card) included in an image with the same light condition. You can just click on the gray card and color is corrected. You can then apply this to all other images taken under the same light conditions. A gray card should have R=G=B in order to not have a color cast. The eyedropper in the RAW converter adjust the image so this condition is met. You can then adjust contrast and saturation to give you the image you want. Adobe RAW converter has adjustments for exposure, black point, brightness, etc. You can adjust exposure by 1 to 2 stops and solve some clipping problems with highlights (this is not possible with JPG or TIF since the image was already processed in the camera). Output 16 bit images with Pro Photo RGB profile and complete other processing in Photoshop - then convert to the profile you want (sRGB, Adobe RGB, etc) and to 8 bits if you are complete with processing.

 

I agree the first thing you need is a calibrated monitor, which requires hardware and software designed to profile monitors. Monitors drift so they need profiling on a regular basis - most recommend every 2 to 4 weeks. If your monitor does not display color correctly its impossible to adjust images correctly.

 

If you plan on printing color you need a good color photo printer and profiles for each paper and ink combination you plan to use. Printer profiles also require hardware and software to generate, or you can use a profiling service to generate these.

[jtk]

Yes, I ranted. Sorry/

 

But I think it's crucial to develop personal visual skills because there's no doubt that all of the profile/calibration skills and process that many depend upon today will be irrelevant shortly.

 

As an example, some printers (the machines themselves) already do their own profiling, and monitors will accurately self-calibrate very very soon...they already do a much better job of that than they did a few years ago.

 

RAW/gray card etc is the most professional approach currently, just as professional Ektachrome that came with Kodak standard color correction advice per batch, coupled with grey card, was always the way to get the most accuracy from chromes.

 

BUT, hardly any "art" photographers or annual report photographer ever bothered with gray cards because the more common chromes were incredibly trustworthy and consistent, for practical purposes. I think that's where this digital technology is going to be in a year or two: don't abandon eyes in favor of gizmos :-)

[godfrey]

Having worked in the photofinishing industry for a few years, transparency film's

"incredible trustworthiness and consistency" is an illusion born of processing machine

calibration and people shooting in simple sunlit conditions most of the time.

 

Pros in that day would do a shoot test, run the film to us for a lighting calibration test,

then go back and shoot the work with the settings that showed the best results. Then

they'd bracket and shoot alternatives anyway, and hope they came out right.

 

Digital capture and image processing makes this SO much easier it's unbelievable. All you

need to do when capturing in RAW format is snap a shot of a proper gray card in the light

your working with and have a properly profiled monitor and color managed workflow for

adjusting and printing the image. Use the tools available in the RAW converter to set the

white balance by the numbers or by eye. Done.

 

Godfrey

[thomas_sullivan]

I realize this is John's question, and perhaps the answer to him is to use a gray card, and in the studio or controlled outside environment, this is definitely the right answer.

 

But, what about those times when this isn't possible? Is there a preferred method of achieving correct color in say a very candid type shooting environment. For example, if you were just shooting a family outing. Just as important to get the colors correct....but my family would shoot me if I brought out a gray card everytime the light change, or we went inside, or under trees, or in the shade.........so, how does one achieve correct colors under these conditions in photoshop etal.....RAW or Jpeg.

[godfrey]

You learn to look for those portions of any scene which should render as a middle to light

gray (not white ... can't base color temperature calibration on something which should be

a fully saturated white point).

<br><br>

In most editing environments (at least those I'm familiar with), there's some kind of

eyedropper tool that allows the application to sample that selection and make color

temperature and tint adjustments to suit. Use it on that patch to get a baseline and then

tweak the adjustment from there.

 

On the other hand, it's excruciatingly easy with a digital camera to have a pocket-sized

white balances card with you all the time. Just pick it out and snap a test exposure with it

in the scene ... use that as a reference for any real photos made in similar lighting.

<br><br>

I like the WhiBal card sold by Michael Tapes at <a href="http://www.rawworkflow.com"

target=new>www.rawworkflow.com</a>. It doesn't take much to do this.

<br><br>

Godfrey

[thomas_sullivan]

...hmmmm, that credit card size one looks really interesting...

[robert_martin5]

You can also use the ExpoDisc and set a custom white balance with the camera. Snap the ExpoDisc on the lens, point the camera toward the light source and measure a custom white balance with the camera. Take the picture using this custom white balance and you should have a reasonable white balance for the image. I have both the WhiBal card and an ExpoDisc - each has its strong points.

[john_sarsgard1]

Thanks for all the input. To answer a couple of questions, I am working with RAW, jpeg, and

tiff images, both 8 and 16 bit. I anticipate in future it will be mostly RAW digital camera

images. I use the ExpoDisc when I can, otherwise AWB. Where I could use the most help is

specific issues like...there's a small green cast...how to remove? Increasing/decreasing

saturation...RGB, or just one channel? What's an orderly way to go about color balance? How

about using hue changes, overall or just one channel? In other words, dealing with various

kinds of issues and the order in which various options should be tried. Thanks again.

[anna_nielsen]

Hi John - to eliminate colorcast open your info palette and mouse over the image to verify a colorcast.(eyedropper set 3x3) If you see ex a red colorcast the next thing you would do was to make a levels adjustment layer and click the white eyedropper.Now find something in the image that could represent white and click on it. (If you have a hard time finding a whitepoint try and hold down alt while dragging the whitpoint slider to the left in levels.) Now u should see fairly equal values in r,g, and b meaning that the colorcast is gone. IF there still seem to be some ,choose the gray eyedropper in levels and now click on a natrual gray point somehwere in your image.If now your values is equal within some few points you have sucseeded. At last you can expand your tonal range by moving the blackpoint slider to tonal information (when the histogram starts) and the whitpoint slider likewise. anna

[robert_k1]

Check out Dan Margulis' books, but you should be an advanced PS user to appreciate them. Even if you are not, the chapter on how to *identify* and use neutrals to remove cast is worth the price. For all levels of PS users, nothing beats PS Artistry by Barry Haynes in terms of details, comprehensiveness and organization.

 

The biggest challenge of color correction is not learning *how* to correct, but identifying *what* to correct. There are numerous books and tutorials on *how*, and very few on *what*. Even with a well calibrated darkroom, if you are not super sensitive and knowledgeable about color hues and saturation (like a b/w printer), you can easily mistake one color as another. E.g., cofusing cyan with blue, green with yellow. While humans think they can accurately identify colors, the sw interprete and represent them (by numbers) quite differently. For the inexperienced, it is very easy to miss a color cast, or to mistaken a certain cast to be something else. Attempting to correct a wrong color (like making a wrong exit on the LA Express) is the beginning of the end.

 

In summary, learn how to see and differentiate colors, and know how each is represented in numbers by sw. (I wish I can suggest how, but I can't other than the chapter by Margulis.) Don't trust your eyes all the time, they will start to lie after staring at the monitor for hours.

[thomas_sullivan]

just got done using and running my first pic thru RAW using the credit card sized WhiBal card sold by Michael Tapes mentioned above. The first surprise is that I actually took the card with me and used it.......heh....Great stuff!