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I work in a college photography program which is a Mac based (OS 10.4) Photoshop CS workflow printing out to a range of Epson inkjet printers (4000, 4800, 2400, 1800).

There are two opinions as to whether or not to "calibrate" our (17" and 20" iMac LCD and 17" Sony CRT) monitors: one side favors calibrating - we have Monaco Optix Pro/X-Rite - as well as printing out using Epson's canned paper profiles. (In my own studio environment with identical setup and equipment, except for using an Apple cinema display LCD monitor, I can now nail a print more or less dead on to match my screen image, again using canned profiles - the technology is that apparently good these days.)

The counter view (from the if-it-ain't-broke-don't-fix-it camp) believes that merely using Apple's Displays preferences panel monitor calibration feature along with an eyeball matching of the monitor to print density (by lowering the Displays' brightness slider) will do the job well enough.

Surely this eyeball seat-of-the-pants approach can't be as good as a properly done software/hardware profile, or can it? On one of our dedicated printer station LCD monitors, I visually compared the "eyeballed" created profile (with its lower brightness slider setting) to the Optix/X-Rite created profile (with its higher brightness slider setting) and they appeared surprisingly close at least by eye (there was a slight color cast to the eyeballed profile). They produced "similar" in-the-ballpark prints.

Is there in fact a slam-dunk argument in favor of calibrated monitors as part of a contemporary workflow? Are software/hardware produced profiles merely only slightly more accurate (in terms of WYSIWYG) than eyeball produced ones? Don't different profiles "translate" colors and densities differently especially in terms of print outputs?

If anyone could shed some light on this I'd appreciate it.

Ray Van Dusen

Montreal

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my personal view, as a lino jockey not a photographer, is that unless you are willing and able to go the whole way (to the intended final output, including on-press) you're only kidding yourself.

On Nov 1, 2005, at 3:15 PM, Ray Van Dusen wrote:

Mac Townsend

Adcom Graphics Digital Imaging

Fairfield, California

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I'm sure there are many of us who find the fully calibrated workflow, imperfect as it may be in its current state of development, to be useful. I think you are doing your students a disservice by not teaching them the full workflow. Profiles of all sorts are only going to get better as time goes by. Teaching them that tweaking a monitor by eye is "good enough" does not lead to well-grounded professionals.

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On Nov 1, 2005, at 3:15 PM, Ray Van Dusen wrote:

No, not really. Very few will argue that monitor calibration is bad, but that's a far cry from getting them to agree to do it. It's a bit like cleaning out your garage. Good idea? Yes. Wanna do it today? No.

I've heard some operators make the claim that they can work on a bad monitor because they rely "only on the numbers." I'd like to see them work on a BW monitor :-)

J

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Eyeball calibration (and profiling) if you can even call it that doesn1t cut it! Your students need to know why. So first, show them how easily the human eye can be fooled (a superb site is http: //web.mit.edu/persci/people/adelson/ and http: //www.echalk.co.uk/amusements/OpticalIllusions/colourPerception/colourP erception.html).

The human visual system is wonderful at viewing images in context. It stinks at placing a device into an absolute and repeatable state. Digital images are piles of numbers and unlike cheese, they don1t age. They only change if you change them and as such, should produce the identical color appearance every time you view them. Since a display does change and out of the box isn1t set to any defined behavior, this means its possible to view numeric values today and in a month that don1t appear the same. That1s not good for anyone that wants an honest view of the numeric values.

Photoshop can only produce a preview of the numbers if it1s provided two ICC profiles; one that defines the condition of an every changing device (your display) and one that defines the scale of the numbers in your files (the color space of your images).

Instruments do not suffer any of the issues scene above and are far better for measuring things (which is why we have rulers, speedometers and other devices to measure things). Instruments are awful at making evaluations of images; that takes a skilled human.

Andrew Rodney

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Ray Van Dusen writes,

Before getting all tied up with concepts like "accuracy", you need to remember what the purpose of calibrating a monitor is. You are trying to get a good idea of what the final output will look like. Assuming that the final output isn't defective in some way, the goal is that when you see it, you shouldn't feel that you would have done the job differently if you hadn't trusted what you saw on the screen. If you have that annoying feeling from time to time, then you probably need to invest some time in calibrating. But if you *never* have that feeling, then you have already achieved 100% of the goal. "Improving" the monitor's "accuracy" does you no further good.

It depends on whose eyeball is involved. The Apple routines are quite powerful. Somebody with a lot of experience should be able to generate a *more* accurate profile than hardware can. But not that many people have such experience.

If you're dealing with students, teaching them how to calibrate a monitor by eye would be a highly useful exercise because it serves as a surrogate for many other types of color problems that they'll face in the future. Get yourself a suite of half a dozen images for which you have reliable output. Don't let anybody touch the monitor's hardware settings, but have each student sit down for 10-15 minutes and try to make as nice a profile as he can. When he's done, save it out, reset the monitor to its original profile, and let the next student have at it. When enough people have tried it, get them all together, load their profiles one after another, evaluate the test images, and decide who did the best job, and why.

Dan Margulis

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Ray,

I have no problem with the "if-it-ain't-broke-don't-fix-it camp" as long as you can educate the students to be able to analyze what's broke when problems do arise. I, as others have suggested, would start with 2 concepts; 1st is color perception, 2nd is variation and drift over time.

Monitor cal's are especially useful when you want to look at multiple units in a studio. There nothing worse than rejecting images for a lack of shadow detail and then finding one monitor was out of calibration because another user thought it need adjusting.

Another question -- do you trust your own eyes to see (for example) a red color everyday and be able to notice if it drifts in hue, tone or saturation over time ???

Lee

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On 11/2/05 6:20 AM, "Dan Margulis" wrote:

Yes, with a product like ColorThink, examine each profile (gamut and what ColorThink calls an actual color set; each LAB value measured). Calculate in that product the delta of each profile.

Now have each student do the same with multiple displays. Compare the differences in how each display behaves by again, using the internal data found in the profile. ColorThink can do this. It can visually show you this in 3D gamut map as well (discussed in my book).

NOW do the same with an instrument. If as Dan says, the delta is very low using visual calibration, you1ve justified his point. For fun, have the students do the same exercise a few days later. Compare the accuracy (and I do mean accuracy, measured using real empirical numbers) with each technique. I'll get you dollars to donuts that the hardware does a vastly more consistent job, day in and day out.

Ask each student to set the same target values and use the instruments. Is there ANY difference? I'll bet not. What1s that tell you about measuring using an instrument?

Andrew Rodney

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Hi Ray

You can make the argument that a photographer who works in a closed loop, your photograph, your eyeballed monitor, your printer at default settings, and your happy with the end result, good that's fine. A quick scan through other forums will attest to the thousands of people banging there heads against the wall and why this system fails. The real problem comes when the loop opens up. You take the same file and start again on a different system set up by someone else to their eyes. It would be amazing if you could get a matched print to your original. The point of software/hardware produced profiles is to get rid of the vagaries of the equipment and allow consistency regardless of who set the system up(in a perfect world).

Malcolm Mackenzie

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In a message dated Tue, Nov 1, 2005 3:15 PM, Ray Van Dusen Wrote:

When monitor calibration is done using "eyeballing" methods -- such as the "Calibrate..." procedure in the "Color" tab of the Displays preferences panel -- the results will depend on how skilled the operator is at correctly interpreting the instructions that the application is asking you to resolve.

What ends up happening is that no two people do it the same way -- which means that (a) one person may do it wrong and the other right, (b) both are doing it wrong, (c) or, if they are real geeky eggheads, they both do it splendidly (an unlikely scenario).

Also, the same person may do it right one time and wrong the next time, due to mood swings, how tired they feel, or even such incidentals as how much coffee they had to drink that morning (and that is not at all a hyperbole).

To make a long story short, I suggest that you bypass this whole array of very tricky variables, and invest the modest amount of money required to purchase a good monitor profiling solution.

My personal suggestion is that you purchase basICColor display (<http: //basiccolor.de/english/Datenblaetter_E/display_E/display_E.htm>) as your monitor profiling software. I believe that the current price for that is $50.

Then get a good colorimeter:

1) either a Gretag Macbeth EyeOne Display 2

(<http: //na.i1color.com/index.cfm/MenuItemID/126.htm>)

2) or an XRite Monaco Optix XR (<http: //www.xritephoto.com/product/optixxr>)

On Steve Upton's Chromix site (<http: //www.chromix.com>), you can purchase either instrument for the same price of $219.

No, no slam-dunk argument there. A sufficiently skilled and gifted operator could conceivably create a good monitor profile via the eyeball method. But human vision is so inherently biased and faulty when making absolute measurements, that even the best of us can have a hard time evaluating all the steps as objectively as a good colorimeter can.

Once you start using good software and good instruments, your results will be far less dependent on the operator's biases, moods and limitations, and just become more reliable.

Good luck.

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Marco Ugolini

Mill Valley, CA