I get them too! I try to get the lighting just right in the house.... kind of dim and you can brighten them up using the enhancing on your picture program. This works for me. But Im not an expert either.....LOL
Make sure you don't have a page protector over the LO first of all.
I always take mine to the porch (all windows) or outside to take a pic. Natural light is best IMO, it makes the colors more true. But it only works if you're getting ENOUGH light. Inside, I almost always have shadows or glare or there's one part of the LO that is slightly brighter than another. If you have good quality lighting (like to take photos with) that works as well, but since I don't, I use the natural light