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Hello Mike,
thanks again for your detailed answer.
I will need to experiment with some of the proposed techniques myself to find out what works best for me. Somehow I was hoping for a miracle button or so, that uses a specific printer profile and makes my image look good on that printer.
I like to compare today’s printer technology to watches. Right now our "color watches" are accurate to five or ten minutes a day. Pretty darn good. If you want to strive for greater accuracy, you can either tweak Adobe Gamma (like the "fast/slow" adjustment of a watch) every once in a while, and set your color watch manually for important images, which is my current approach – or try to get a watch that is more accurate. This costs money, and may or may not pan out. There is a lot of fluff out there right now, and much money is being spent on profiles that introduce banding into your image.
Furthermore, and this is the most important, complete color accuracy reaches a point of dimiishing returns, and manual adjustment will generally yield a better result than any automatic process, however well calibrated. I think the greatest rewards, in terms of actual image appearance, come from knowing how to do good color correction, and the Curvemeister plugin is dedicated to this goal. As Hecate said about sharpening, connecting your brain to what you are doing is the more important thing.
The way I understood RelCol Map to work is that only the out of gamut colors are mapped back to fit the specific color space. If I have a large range of colors outside (who knows how much really lies outside), this can lead to posterization, as they are all clipped to the border of the color space.
Yes, the color is mapped to the closest matchine hue and saturation, preserving luminance. This is generally a good compromise because the variation in luminance renders the hue clipping unnoticeable. The trick is to anticipate when this will not work, and use desaturate or some other technique to compensate for it.
Anyways, I guess the right thing to do is play around a bit and figure out what works best for me.
Certainly – or at least try to verify the things you read here and in other forums, and judge for yourself whether it is meaningful. We are at an early point in the evolution of color correction and color calibration as applied to photography. This makes it an exciting time, because there is so much new out there, but it also means we have to weed out the stuff that sounds good, but doesn’t really pan out.
I have calibrated all my monitors with the Spyer2 (I returned Spyder after finding out it doesn’t work well with LCD). I am mainly working on my laptop for convenience, even though the display really sucks (Compaq V2000). I have calibrated it though and it should be reasonably close. If I keep a constant viewing angle it should be allright.
If you have a CRT lying around, try plugging it in and see how the colors compare. In particular, make sure that you are able to distinguish colors that are different on the CRT, and that you don’t have an overall color cast.
Interestingly, the out of Gamut colors will stand out when I view my laptop screen from below (tilting the display back all the way). This came as a surprise to me and seems to indicate that those colors really need some work. I have a reddish-yellowish bright patch. The out of gamut warning shows for the whole patch and when I tilt my screen the patch is all I can see at some extreme angles.
OOG colors will tend to show up because you are driving one of the display channels at its brightest value. Changing the angle of your LCD tends to blot out the darker values more abruptly, because LCD’s are based on a light polarization phenomenon.
As for your little puzzle 😉 :
Is the printer a CMYK printer? Have you viewed the result in different lighting conditions (e.g. fluorescent, daylight).
No – it’s an RGB inkjet. I’m thinking of changing the puzzle to invite people to try printing the image on their own printers. Blue cobalt is a devil of a color to print – the glass turns opaque so easily.
I don’t understand enough about printing, my best guess is this: A CMYK printer has to mix blue out of some other colors. For a dark blue, there is prob. a RGB of 0 0 30 or something like that. Now if you have to mix this out of different colors, each color in the mix will be even more subdued and spread out (the printer does not make bright or dark pixels) among the black (to get it dark).
So maybe one out of 50 pixels will have a color value.
Depending on your paper, that may even bleed into the black and vanish or be noticable as "random" color specks.
What you are saying is accurate. The question remains whether we can actually analyze what is happening to the soft proof stage first, and then take that further to the actual printed image. This article is a work in progress, and I would like to invite others to share their ideas and thoughts.
Like I said I have no idea what really happens. Seems like printing technology has yet to catch up to modern camera technology. I also noticed some posterization in the bright blue areas (or is it just me?).
Possibly – it’s internal glass reflections, which can look like posterization.
On a related note, where can I get ProPhotoRGB profiles? I am not sure I saw it in Photoshop.
I believe it is downloadable from
http://www.dodgecolor.com/downloads.html Also I like your website and your tutorials. Seems like I should give Labmeter a try, although I have a little trouble understanding these color space representations. I am not sure if yours is different, but generally they map a 3D color space onto a 2D display and thats where the confusion starts for me.
Thanks for the kind words. LabMeter shows a slice of the color space. Open up the curve adjustment layer and move the whtie end of the Lightness curve up and down, and you’ll see different slices at each lightness value. —
Mike Russell
www.curvemeister.com
