With the filter opened up you can see what has been being filtered. You can look for converter material and basically "chunks" of stuff. The dark around the edges is normal and what you see here is pretty typical of a normal wear in the tranny. If you have any questions or concerns about what you find in your filter, ask a buddy who might know or even take the filter to a tranny shop for them to inspect. You might be able to find some serious things about to go wrong in your tranny by inspecting this filter and it will be better for you to get it repaired asap than to get stranded someday on the side of the road!