I recently purchased a pop up diffuser flash similar to Gary Fong puffer from an online store. when I mounted it on, I noticed that the flash cannot pop up fully, the diffuser bracket is obstructing. when I looked for images of the diffuser while mounted (I mean gary fong's) the pop up flash looked upright so I said to myself, I should do something about it. So I cut off the portion of the bracket that was obstructing and I managed to get it done.
Now the problem is that when I take shots at 17mm (using a sigma 17-70), I noticed that the bottom portion of the image is distinctively brighter. when I mounted it lower (the diffuser have 5 slots for height), its the top portion that is brighter.
Im now thinking was I wrong that I cut off the bracket? should the flash be really facing down a bit?
was the diffuser suppose to be wider than what i got?
will attach images when available.