I have the same problem with blurry images (since the app doesn't have option to set camera parameters - would be nice option to have it). Tried mid flight to exit app (while drone was hovering), go into DJ native app, check camera, but picture was good. Went back to 3dsurvey and picture again blurry.
I'm flying a mavic 2 pro using smart controller, and I flew the linear mission 1st with double line, after tried single line with same resulting blurry images.
All images are in 3:2 ratio (not able to change for some reason, or I'm missing something), blurry (yet in other apps all is good), and picture oscillating from darker to lighter even between two sequenced images.
Also on a side note, for some reason the app on the smart controller is upside down and no idea why.
When I looked at the images, shutter speed was fluctuating a lot (never happened before in other apps) which can be the reason for lighter / darker images, but then the question - why does it fluctuate?