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Old December 15th, 2009, 01:11 AM   #1
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Default Color correction

This is a somewhat controversial subject. Some people think that a scanned image shouldn't be color adjusted, that you should leave it as is because that's the way it was printed.

My feeling has always been that if the people look orange, yellow, or pink, as frequently is the case with old style porn mags of the late 70s/early 80s done with a cheap printing process, something should be done about it to make it look more realistic.

The problem: How to go about making it look more realistic. There are a several complications to take into consideration here including but not limited to...

1) Monitor quality - is the image being displayed on the monitor accurate. This was a problem back 10 years ago and it's even more of a problem today with the dominance of LCD monitors. For years after they hit the market I kept avoiding LCDs. CRTs, despite whatever inherent flaws they may have in terms of color accuracy, didn't have the additional problem LCDs continue to have to this day in regards to viewing angles. I have yet to see an LCD that didn't do some sort of color/brightness shift in parts of the screen where you weren't looking head on. Do this: plant your head in one direction at your LCD and then move your body left/right/up down parallel to the LCD. You'll notice that the parts of the screen not directly in front of you will shift in brightness and saturation, with the parts of the screen not directly in front of you losing contrast and saturation as you move your head. This plays havok with ones ability to properly assess an image's correct color and contrast.

2) What did the original photograph look like? Since the the vast majority of printed images are either over saturated or tinted badly you really don't know what the photograph was supposed to look like.

What I have been doing is using a rather fluid set of procedures to get the flesh tones more realistic. But it's a process that has produced a lot of hits and misses. Sometimes I just can't get the fleshtones right. This is particularly true for images that skew pink, less so for images that skew red, orange, or particularly yellow.

I start off by de-saturating the image in Photoshop. The amount of de-saturation depends greatly on the level of saturation the image has. Sometimes I have to desaturate by a level of -40 in extreme cases.

I then open up color balance and do further adjustments, usually lowering the amounts across the Shadows and Midtones but being more delicate with the highlights. This is usually a two stage process where I do an initial pass and then make refinements in a second pass, mostly to the Midtones and some Highlights.

I then follow up by adjusting the Levels to add contrast. Only after I'm done color adjusting do I downsize the image to 72 DPI and whatever dimensions I think the image is capable of supporting without losing detail.

This process is far from perfect and I'm constantly looking for ways to improve upon it. I'd be interested in hearing any ideas for color correction. I've dabbled with curves but that's a process I just can't figure out properly.
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