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Guest

I checked the high FPS mode on my Sony A55 regarding mostly the exposure settings.



So, here are the findings.

- it is a kind of aperture priority mode, and there are no restrictions on the value you can choose; I verified f/2 and f/5.6 on 28/2 lens;

- you need to set the aperture before the burst, and cannot change it in the process;

- moreover, the exposure is locked too; if you use manual lens and change aperture, the camera won't compensate;

- focus is locked in AF mode.



If you ask my opinion, I think it's a very clever decision not to *-ck the lens 10 times a second; it's expected to serve much longer than the camera.



Hope this helps,

Oleg.

Guest

Correcting myself a bit:

- you _can_ select continuous AF in high-FPS mode, and it somehow works; not sure it's very efficient though

- light metering isn't locked; I noticed exposure time changed from 1/125s to 1/100s during the burst
This is very interesting. If the A55 allows the aperture to be selected before the burst, then it's very likely that the A77 allows it too. In which case there's really nothing left to complain about. In fact, the only other camera which can shoot at similar framerate (the Nikon D3s) has similar, or even worse limitations:



- 5MP resolution only, due to the crop to APS-C which the Nikon forces when shooting in 11 fps. The A77 can do 24MP at 12 fps which. Unlike the D3s, it is still a good choice for stock photography and enlargements even at its top framerate.

- No AF tracking. Focus is locked after the first shot. It's going to be interesting to see how well the A77 can track subjects at 12 fps. If the lens is wide open or stopped down a notch it should still be pretty good, as unlike DSLR's the SLT design allows the AF sensors to continuously "see" the subject.

- Exposure is locked after the first shot. According to the test above by olegk, the A55 does not suffer from this limitation. I don't expect the A77 to have this limitation either.



The one advantage the D3s have in this mode is the much larger buffer. Good for 130 shots which is ten times larger than the A77. I guess those who are willing to give up the other advantages for the larger buffer will need to wait for the A99 :-)

Guest

[quote name='boren' timestamp='1314688107' post='11159']

This is very interesting. If the A55 allows the aperture to be selected before the burst, then it's very likely that the A77 allows it too. In which case there's really nothing left to complain about. In fact, the only other camera which can shoot at similar framerate (the Nikon D3s) has similar, or even worse limitations:

[/quote]



Yes, you can set the aperture manually but then there is no AF-C. With AF-C, the aperture is fixed to F3.5 (or wide open if F3.5 isn't possible).



In 8 fps mode, you have full exposure control.
[quote name='Sathe Wild' timestamp='1314828682' post='11211']

Yes, you can set the aperture manually but then there is no AF-C. With AF-C, the aperture is fixed to F3.5 (or wide open if F3.5 isn't possible).[/quote]



In other words, the A77 allows the user to control the aperture in 12 fps mode, but locks focus (like the D3s) if the user selects aperture value that smaller (narrower) than wide open. However, unlike the D3s it can focus continuously if the user selects the wide open aperture. This still puts the 12 fps mode way ahead of the Nikon when it comes to AF, AE and resolution, and only trailing it in buffer size. Not a bad trade-off, and certainly not a reason to complain in a camera that costs less than a third.