speedmaster20d wrote:
duncangr wrote
speedmaster20d wrote
Fred Miranda wrote
Steve Spencer wrote
duncangr wrote
BTW thanks, you didn't happen to test in APS-C mode did you. Hopefully Arash can give us an actual measurement, but it should be basically a function of the crop factor so something close to 13.1 msec (i.e., 19.7 / 1.5) in RAW or lossless compressed or compressed HQ and 9.4 msec (i.e., 14.1 / 1.5) in lossy compressed. This seems right to me, and getting around ~9 ms in APS-C (lossy compressed) actually makes it a very usable option for action shooting. I don't remember exactly, but I think the original A9, the one that made a lot of action photographers switch over pretty quickly, was around 5-6 ms. unfortunately that does not help. it is the scan slope (time to read a single row) that matters not the total readout time. The distortion is a function of panning speed relative to the scan slope. I checked and the slope does not change in APS-C crop. the distortion will look identical i.e. it will look same as just cropping the FF image in post.
I agree the ciritcal readout time (beyond which is almost don't care) appears to be about 5-6 msec for a FF sensor (or 3-4 msec for APS-C).... so the A7R6 falls short by 2.5X in best case scenario
the issue I take is the strong emphasis Sony has put on "ready for pro action" for this camera... not true advertising IMO. Otherwise it's fine for what it is. But if you have the same FOV in APS-C mode as in FF mode then the slope will be quite a bit less. As you rightly point out cropping alone will make no difference. the slope does not change in APS-C mode, it's the same. Slope is limited by sensor electronics not FoV or anything like that.
if you want to get same FoV in APS-C as FF you have to walk quite a bit back from the bird that will reduce the rotational speed as you pan from much farther away and makes the distortion less .... but no one would switch to APS-C and the walk back from the bird to end up with a low resolution image of a far bird.... doesn't makes sense really
If you fill the frame with a swallow flying towards you in FF mode the distortion will be greater than if you fill the frame on the same bird in APS-C mode.
Why would you do that in FF mode - more pixels = more detail.
Why would you do that in APS-C mode rather than just cropping - potentially better camera performance and less distortion, longer buffer, better AF, EVF etc. assuming of course those do realise a benefit in APS-C mode.