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Old Sep 6, 2010, 6:03 PM   #21
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That ~300 shots is a CIPA Rating, and assumes things like the default image preview features turned on, use of the flash for a percentage of the images, time the camera is turned on and supplying an image to the EVF or LCD, and more.

I'd expect much better battery life from a number of photos perspective if using burst modes and taking a lot of photos in a short period of time. ...
I suspect you're correct, but those same assumptions apply when the CIPA Rating for the battery life of the A5XX is determined. Either way, the A5XX is likely to get about three times as many shots from a single battery as an A33.

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... But, I'd still buy a spare battery or two. ...
As would I, even if I were getting an A5XX.

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...No big deal if you value the smaller size/weight, EVF, etc. of the newer models.
But if you buy and carry around as many spare batteries as it would take to take as many photos as an A5XX would get with two, that whole "smaller size/weight" thing becomes less important. Especially if you have to run them all through a singel charger, so you may need to get an extra charger to keep all those spare batteries charged.
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Old Sep 6, 2010, 6:13 PM   #22
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1/3 stop light means losing 33.3 Percent of the light (about what you'd lose with Sony's mirror. No big deal. That's like the difference between ISO 3200 and ISO 4000 (and the newer sensors are around 1/3 stop better from a noise/detail perspective anyway), and thanks to the amplification of the signal going to the EVF, you'd see a brighter image compared to an OVF for framing (as compared to the 1/3 stop dimmer view you'd have using a Pellicle mirror design with an SLR that has an optical viewfinder).
No. One stop is half (50% of) the light. When you stop down from f/2.8 to f/4.0, you must double the exposure time because the aperture is letting in half the light. If you block 30% of the light you're losing 6/10 stop (roughtly 2/3). That's the difference between ISO 3200 and ISO 5000, or between a shutter speed of 1/500 and 1/320.
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Old Sep 8, 2010, 12:35 PM   #23
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Yes, 1 stop is half the light. But, as for the loss through the Sony mirror design, we're both wrong. It's closer to 1/2 stop. :-)

Here's the formula:

EV change = log2(Transmission)

So, with 70% light transmission to the sensor (which is what I'm seeing quoted for the new Sony mirror design), this is what it would work out to:

EV change = log2(0.70) = -0.5146EV (approximately 51/100 of a stop, making it closer to 1/2 stop).
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Old Sep 8, 2010, 1:22 PM   #24
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I'll buy that. Thanks for the effort.
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Old Sep 8, 2010, 2:19 PM   #25
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Yes, 1 stop is half the light. But, as for the loss through the Sony mirror design, we're both wrong. It's closer to 1/2 stop. :-)

Here's the formula:

EV change = log2(Transmission)

So, with 70% light transmission to the sensor (which is what I'm seeing quoted for the new Sony mirror design), this is what it would work out to:

EV change = log2(0.70) = -0.5146EV (approximately 51/100 of a stop, making it closer to 1/2 stop).
Thanks for all your hard work. It was an interesting topic. I think I'd still go with the a500 than the a33. I'm not sure if the EVF would be able to keep up with action like at my son's basketball game.

But hey, I may have found myself a research topic for a paper I have to write in applied mathematics
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