new sony dslr or dslt(none moving mirror)

You lose 30% of the light entering the camera to the AF system. I suspect this will hurt the low-light performance of the camera somewhat.
 
Unfortunately it doesn't seem to work very well. The AF servo can't track properly at high frame rates, and the viewfinder blacks out :shrug: In addition to other drawbacks, potential or otherwise.

It fails in its quest to solve a problem, that wasn't really troubling anyone anyway.
 
HoppyUK said:
Unfortunately it doesn't seem to work very well. The AF servo can't track properly at high frame rates, and the viewfinder blacks out :shrug: In addition to other drawbacks, potential or otherwise.

It fails in its quest to solve a problem, that wasn't really troubling anyone anyway.
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I suspect the viewfinder blackout is due to the camera having a conventional mechanical shutter installed...
 
HoppyUK said:
Unfortunately it doesn't seem to work very well. The AF servo can't track properly at high frame rates, and the viewfinder blacks out :shrug: In addition to other drawbacks, potential or otherwise.

It fails in its quest to solve a problem, that wasn't really troubling anyone anyway.
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What are you basing that on? - the review I read (Luminous Landscape) seemed to think it handled high speed AF very well.
 
mustanir said:
I suspect the viewfinder blackout is due to the camera having a conventional mechanical shutter installed...
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Viewfinder blackout is not quite the right description. Apologies for the confusion.

What you loose at high frame rate is live view, and the viewfinder shows you the image you have just taken, rather than the one you are about to take. DPReview suggests that this makes the camera unusable for panning as what you see in the viewfinder is obviously not what the camera is pointing at. See link below.

Faldrax said:
What are you basing that on? - the review I read (Luminous Landscape) seemed to think it handled high speed AF very well.
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DPReview disagree. It's here, page 8 of their hands-on preview http://www.dpreview.com/reviews/sonyslta55/page8.asp
 
To be fair Richard DP review say that it doesn't work properly at 10fps and 6fps which is a higher frame rate than almost every other DSLR in the same price range. At 3fps which is more than enough for most people at this end of the market it's fine, or at least I assume it is fine as DP review chose to not comment on it (seems like a back-handed compliment to me).
 
But one of main reasons they have this translucent mirror thingy is for a faster frame rate, but you cant really use it for fast frame rate because you cant see what you are shooting at the fast frame rate?

Or am I being thick? :)
 
jonesy_ni said:
But one of main reasons they have this translucent mirror thingy is for a faster frame rate, but you cant really use it for fast frame rate because you cant see what you are shooting at the fast frame rate?

Or am I being thick? :)
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actually you can see what your shooting, in the days of conventional mirror it would black out for every shot and so high speed shooting would be like walking around constantly blinking, whereas this enables you to still have the viewfinder available and shoot at high frame rates.
 
jonesy_ni said:
But one of main reasons they have this translucent mirror thingy is for a faster frame rate, but you cant really use it for fast frame rate because you cant see what you are shooting at the fast frame rate?

Or am I being thick? :)
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No, that's exactly what I think. The camera can't actually deliver on what it was designed to do.

It's almost as if they came up with a bit of trick technology (which has been around since the 1960s actually, and didn't work then either) which the marketing department latched on to, but nobody thought to test properly :shrug:
 
jonesy_ni said:
But one of main reasons they have this translucent mirror thingy is for a faster frame rate, but you cant really use it for fast frame rate because you cant see what you are shooting at the fast frame rate?

Or am I being thick? :)
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The point of the translucent mirror is to allow phase detect AF while shooting video - with a 'standard' DSLR you have to use contrast detect AF, which is not as accurate.

See http://www.dynaxdigital.com/the-digital-dynax-diner/canon-550d-vs-a55-af-test/ for a link to a video demonstrating this.

Interesting the Luminous Landscape review did not encounter the problems with high speed shooting (or if he did, it was not mentioned), perhaps there was some variation in the pre-release samples? Time will tell.
 
mastertrinity said:
actually you can see what your shooting, in the days of conventional mirror it would black out for every shot and so high speed shooting would be like walking around constantly blinking, whereas this enables you to still have the viewfinder available and shoot at high frame rates.
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No, it doesn't. Live view doesn't work at the two higher frame rates and what you see is the picture you've just taken. When you're panning, you don't know what the camera is actually pointing at - except that it is not pointing at the subject, which is also most likely to be out of focus (apparently). See DPReview.
 
HoppyUK said:
No, it doesn't. Live view doesn't work at the two higher frame rates and what you see is the picture you've just taken. When you're panning, you don't know what the camera is actually pointing at - except that it is not pointing at the subject, which is also most likely to be out of focus (apparently). See DPReview.
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I find your argument a bit negative. When panning is it not the first couple of frames that count, once speed is established then the following frames become less relevant for following subject. Personally when panning I use both eyes one on the camera and the other spotting the subject.

I do find I lose the subject when panning with one eye closed and the other on camera.

Although one image being a tenth of a second behind I don't know if there would be a problem with that technique.
 
If you switch off post image capture review does it still blank out in the same way? It would also give the camera less to do.

I am tempted by the A55 as higher speed shooting would be good along with a video mode as I do miss it with the A350.

We have found however that after manually unlocking the A55's mirror we can persuade it to sit slightly outside of its clip - i.e. at a slightly less acute angle to the sensor than it should be. This causes severe image ghosting but is otherwise impossible to detect.
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Question remains whether the ghosting was there before they messed with the mirror and didn't get it back properly. I'd hope future versions would have locked mirrors and built in sensor cleaning to avoid having to mess around with the internals.
 
So is there no optical viewfinder at all on these cameras?
Oh, and contrast detect AF isn't less accurate than phase detect. Slower? Yes, but it's potentially more accurate than phase detect.
 
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