I've noticed a lot of posts to the forum that really suffer from going down to the 200K limit imposed on a post. Many photo editing programs have a feature where you can optimize for a web pallet or a pallet that is optimized for your picture. Optimizing for your picture is best! Also you should look at the dithering setting and the lossy setting if available. This post only uses 256 colors! and yet it looks almost identical to my original which is 4 times as large. I often see a lot of banding where there are similar solid colors like in skies. There are also artifacts of noise and patterns in some posts. If you are going to take the trouble to get feedback on your art, naturally you want to show it off as best you can given the constraints.