What is this artifact?
This is not my house - it is a photo I borrowed from the web to show artifact. Do you see it? What is it called?
My question is: did this artifact come from the camera itself or did it happen during post-processing or uploading? This was taken with a Nikon D40, and a lot of photos I looked at (on the web) from that camera had this artifact. If it's from the camera, it's unacceptable to me.
I also saw it in photos taken with the Rebel XT, XTi and G3. I mostly see it in the interior shots - which is what I'm wanting to shoot better, hence my search for a new camera. The thing is, I don't remember ever noticing it in photos taken with my little P&S, so I'm wondering if it's from uploading or the SLRs or what. Here's another example: