SkedAddled wrote in post #18932048
Would you care to elaborate?
I'm sure more than a few of us would like to know your thoughts.
Keep in mind that I purchased 90D to go specifically with my Sigma 150-600C for birding and wildlife. Prior to this, I used 5D IV with the Sigma, so my comments are in reference to my experience with 5D IV.
My initial findings showed two major disappointments:
1) Noise, noise, noise. At ISO 800, noise is quite apparent, so NR to deal with in PP. It just gets worse at higher ISO. To me personally, Auto ISO was unusable when it jumps to high ISO because of too much noise.
2) Lots of hit and miss with focusing and resulting sharp images. Hand-holding at 1/600sec, which was no problem with 5D IV, yielded zero keepers. It improved at the minimum 1/1000sec hand held and improved more still on tripod. Of course, hand-held results would be quite different with lenses with IS.
3) Underexposed photos, I found, are harder to salvage in PP or simply unsalvageable. With 5D IV underexposed images, I can bring them back to life, no problem.
I now realize that I've been very much spoiled by 5D IV unaware, so my findings on 90D is because I'm coming from 5D IV. If you're coming from 70D or 80D, I'm sure everything about 90D would appear an improvement, so no disappointments to deal with. I know that it's not fair to compare a full frame to a crop body, but that's the only experiential reference point I have.
I'd be inclined to keep the camera if I only had the issue 2), but 1) isn't simply acceptable for me. For birding and wildlife, one has to use high ISO very often, and I don't want to battle the noise in PP all the time with 90D.