Screenshots

Hello, I am trying to find in the net but I can't find anything about it, so I would like to ask if anyone ever had that problem and know how to make it perfect. Thank you.

I create paintings for players then I make screenshots as previews to put them in my blog. But I have problems with some frames/paintings, when I take the shot, the backround is too bright. I put a sim in the house, the paintings, then I use the setting with the sim, not the construction setting, and then I click the tab function so that I can move well up/down, left/right, but with some paintings it's too bright. You can see my screenshots, any idea what I can do, I have tried different ways but I gave up.