On Photoshop 6.0 I was able to adjust the contrast of a grayscale pdf image by going to image-adjustments-brightness/contrast,increasing the contrast, hitting ok. I could then save the image file. I just obtained Photoshop CS3 and things do not work that way. I do not see any change when I increase the contrast. However, I see an increase in contrast when I lower the brightness, but when I click ok, the contrast goes back to where it was.
How do I increase the contrast and save the image?