Blue Heron Taking Flight

Got pretty close to this heron with my Poke Boat before it lifted off.

I think I just figured out something about posting. For emailing to mags, I process my pix at 5x7 and 400 dpi. To post here, I've been taking those cropped images back into PS and cropping them again to bring them way down for an acceptable posting size, and I'll bet the extra cropping is degrading the image.
Any suggestions?

You don't need to fiddle with the document size (5x7) nor the resolution (400 dpi).

Just reduce the native pixel size (example 4752 x 3168) down to what you need (800 x 533). Try it and post the same image again here.

Thanks, Loupey. But how do I do that?

From your Image Size tool, you simply change the current pixel size (after your final crop) - shown here is 4752 and change it to 800. As long as you have the Constrain Proportions enabled, the smaller dimension will change automatically.