Expert: LizaL - 9/12/2005

Question
Photoshop CS for a mac.
I opened a file. I wanted to adjust the color so I choose auto level to see what type of correction it would apply. The image turned all dark with a purplish red shade. This never happened before. It is now happening on all my photo images when I use auto level and auto color, too. I went to my other computer and went through the same process and it worked correctly. Why is it so dark on my Mac computer. Can you please help me out.

thank you.

mike

Answer
Hi Mike,

Since auto levels and auto color seem to work on one computer and not the other (the Mac), it sounds to me like a hardware issue.

1. Make sure your monitor is calibrated (on your Mac).

2. You should have an Apple Hardware Test CD that came with your operating system. Run the diagnostics found on the disc, and see if something could be wrong with your video card.

3. If all else fails, reinstall Photoshop. But make sure, before you do, that you delete all the Photoshop preferences from your machine.

4. Do you have two monitors connected? If so, try removing one.

5. If you're running one monitor, make sure it's connected tightly. I have two monitors, and the cable to my second monitor doesn't have the greatest connection. When you don't have a good connection, you don't always get true R,G, and B. Sometimes the cable can get jostled and cause the monitor to just display one of the three colors and not all three at once -- which has happened to me -- so check and make sure your connection is tight.

6. Also make sure your monitor cable isn't damaged in any way, and that the pins are all making connections where they should.

7. If you're using a monitor extension cable, stop -- hook the monitor directly to the Mac -- and see if this changes anything. If not, the problem most likely is your video card.


If the problem is isolated to this computer, then it's probably not Photoshop, and the reinstallation would be your last step. It sounds very much like a hardware problem.

Hope this helps --

Lisa