The point about shutter durability is quite valid and this could be a concern for some buyers. You could have effectively halved your usage of the camera with additional wear also high fps shooting doesn't do shutters a lot of favours either. Yet Sony don't seem to quote a shutter rating for some odd reason?
I'm also not seeing a stampede of Canon and Nikon owners demanding SLT type cameras either..

Until we get something out there concrete and with full details it's just stabbing at the air. I have no doubts it will be good because it surely has to be this time around. On the other hand it might be a bit premature to suggest this is "the one to break Canikon" it's going to need some very good design and handling no silly mistakes this time around either. Sony have to nail it to the wall and securely. Then it might have an impact. But as has been said many times some buyers are not into SLT and are aware there are some IQ compromises (albeit small ones they are there) there is a certain "gamble element" to this release.

I understand that there are more enthusiastic people on, lets say, DPR. but I don't think the point of view you are defending is "winning" over we, the old grumbling...

Sorry for not sharing your appetite for cutting the King's head off...
The closest thing near a revolution that I support is the NEX system.

Thanks for the explanation. I just hadn't thought much about it. Is there much of a shutter lag with the A55/A33? I suppose that even with the double shutter action it would be no worse than an SLR with the mirror/single shutter action though.

By the way, do digicams without a focal plane shutter operate the same way?

Sorry Henry I don't know much about how various compact (I assume) camera shutters work, I think most would have an in lens leaf shutter but I would only be guessing. Apparently the CMOS sensor design lends itself to a digital shutter where they can do resets of the readouts but I have no idea if any brand is actually employing any such method.
Greg

I always assumed that digicams use a lens leaf shutter so I suppose it has to do the same as the A55's focal plane shutter: stay open while using the LCD and then when you press the shutter button the shutter closes, opens for the exposure, closes, and then reopens.

Does any camera use a digital shutter?

Yes Henry and some may use some combination of the reset option with the shutter, the shutter performs double duty serving as an f-stop iris as well, it could open up to the predetermined f-stop and then the camera does a reset records all the sensor output at that moment and then the ‘shutter’ opens back up all the way again. There may only be two available auto f-stops on small compacts with slow-ish lenses anyway.
Greg

Will be interesting to see if they put a shutter rating on the A77..

Here is a quote from a non-photo forum I would like to share....


It came from a long time cannon shooter...

The discussion there has centered around what sony's move will be with regards to their sensors and Nikon. Do they continue to make money selling sensors to nikon/pentax or do they start to squeeze Nikon a little and put pressure on their R&D facilities ($$) to develop their own.

There has be lots of upward price pressure (slow but constant) for CaNikon as production facilities for both were in the earthquake zone. It's been hard to find certain models and lenses in stock as they have depleted their existing reserves. The $1000 A77 could put some real pressure on the big two to lower prices, (I've always felt both were overpriced, Nikon's more so than cannon.) It will be interesting to see what happens.
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Lonnie Utah, I would say that the sensors are made by a different Sony division and their objective is to maximise sales and profits. If Nikon and Pentax want to buy I am sure they will be offered products. I doubt that Sony Alpha division alone can provide a sufficiency of orders to justify the investment in the sensors.
Take the 16Mp sensor. It is now used by Nikon and Pentax as well as in the Sony A580, A55 and NEX-C3.

Only because of where sony is now in the DSLR market (#3). If they are overtake Nikon or canon, then then it make sense. But to get there, you have to take out the competition. I think the Nikon folks are worried. Thom Hogan was slumming around sonyalpharumors today.

You are thinking short term and not long term. If you are going to dream, dream big...

Why yes, I believe many do - when taking video. My question is, if you can take 30 (or 60) fps in video, why can't you have a silent digital shutter for stills? There must be a reason - but what is it?

Then why don't camera companies offer a "Ultra Speed Mode" where you take 20 FPS with the physical shutter held open and the digital shutter controlling exposure?

Dusty

I would be happy if they just did a high speed mode, where they just take 2 exposure per mirror cycle, that would give me 10 fps on the A550 with AF, then super high speed with 3 exposures per mirror cycle for 15fps with a refocus every 3 frames, That would allow A55 to take 30fps, for 99.99% of situations a refocus every 3 frames would be fine?

THe issue with capture rates like that is the ability to write that data to a memory card, esp if shooting RAW.