Hello, I'm hoping somebody can offer some possible causes of the light corners I get in all my prints. When I print, regardless of which negative I'm using, all four corners are much lighter than the center of my print. If it's not an area that's going to be covered by a matt, I spend extra time burning in those areas, but this seems like a lot of extra work. Any ideas of what could be causing this? I'm new to b&w photography, so please don't hesitate to state the obvious. I'm printing on ilford multigrade IV, from 35 mm negatives. I"m thinking it's not in the negatives?? Any ideas or suggestions are greatly appreciated.