How do I adjust images in 1.8 gamma to 2.0 in Photoshop?

April 5, 2008 1:19 AM

How do I adjust images in 1.8 gamma to 2.0 in Photoshop?

I'm new to this whole Photoshop and color profile thing. After spending many hours editing countless pictures, I discovered that images look darker on a PC (I'm on a Mac). Many sites suggest changing my display to 2.0 or 2.2 and work on the editing in that gamma. Ideally I would like to avoid re-editing all the pictures. Is there a way in Photoshop to readjust those images so I can set an action and batch update all the pictures?

posted by herbiehancock00 to media & arts (5 comments total)

Gamma adjustment is most easily done in ImageReady (I think this comes with all versions of Photoshop, although I could be wrong). Use Image -> Adjustments -> Gamma and use the slider to set the amount of change you want to make to the gamma. This of course means you can only change a batch of images by the same amount, so if your source images have different starting gamma values, you may have to adjust them individually.

Not sure if this is entirely relevant, but if you're producing PNG images for the web, the best thing is to remove all gamma information in the file, because individual browsers (IE being of course the main culprit) interpret the gamma information differently, so the images can look weird. TweakPNG is a nice tool for doing this (use this version for handy command-line / content menu functionality).
posted by le morte de bea arthur at 3:16 AM on April 5, 2008

I suggest you run adobe gamma on your pc to adjust the screen settings. Your goal should be to match your pc and mac monitor. There's no need to change the color information in your pictures if they already look good on the mac.
posted by SurrenderMonkey at 3:57 AM on April 5, 2008

SurrenderMonkey: I'd imagine that the problem for the OP is that they'll look too dark on most people's screens.

Herbiehancock00, I'd go to System Preferences and go to Display. Then click on the Color tab, and click calibrate. Turn off Expert options and go through, just making sure that you've set the gamma to 2.2 and the white point to D65. Save it as a new colour profile and use that one in the future.

Btw, they've discontinued ImageReady, so it doesn't come with current versions of PS.

What might be a good idea is to set your gamma to 2.2 and work through maybe 5 or so photos, looking at how much brighter you need to make them to look good on a PC. If you find that it's a similar amount, just batch apply that to a whole bunch of photos.

Btw, if you're saving JPEGs for the web, make sure that they're using an sRGB colour profile. That'll make sure that the colours are about as close as can be in most browsers.
posted by Magnakai at 5:21 AM on April 5, 2008

Color calibrate the PC monitor first. It's probably set up incorrectly (as are most peoples).
There's plenty of standard test patterns out there, or you can use a couple different products like this one to assist you in the calibration.
posted by whoda at 6:39 AM on April 5, 2008

On the Mac, at least, if you don't want to invest in an actual calibration tool, I've found that SuperCal does a pretty darn good job at monitor calibration for a software-only solution. It's heads above the Adobe tool.
posted by Thorzdad at 12:30 PM on April 5, 2008