I'm not sure if my problem is a setting in photoshop, or my monitor is dying or my video card or all of these things. What I am experiencing is mostly evident if I am working on a B&W image in RGB mode in photoshop. When I'm finished working on the image and 'save for web' and view it in windows image viewer or a browser, the image inevitably displays much brighter, but if I open the same image up in photoshop, it appears darker. I am so frustrated. Hoping someone can help.
Thanks.

It sounds like a color management problem. What color space are you working in? What are your Color Management settings? Photoshop manages color but Browsers do not.
Regards, Murray

Hi Murray, thanks for your prompt reply. I think I've figured it out. In the 'proof setup', I was working in CMYK and changed it to Monitor RGB and now the image appears the same in photoshop as it does in the browser. :) I'm so glad it wasn't my monitor or video card.
Thank you.