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04-05-2009, 07:35 PM   #31
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QuoteOriginally posted by alohadave Quote
Interesting. I just picked a Ricoh Singlex from the early '60s that uses a similar shutter from Copal.
Copal has been making those vertical run electronic shutters for all brands for decades. Another maker is Sekio but their shutters are minority.

04-05-2009, 07:37 PM   #32
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QuoteOriginally posted by Jonson PL Quote
The Nikon D1 had Single-blade mechanical shutter. And the D1x had Charge-coupled electronic and mechanical shutter. They could go up to 1/16,000 sec. With flash sychronization up to 1/500 sec
I don't think there is any "single blade" mechanical shutter on Earth for use in any DSLR/SLR.
04-05-2009, 08:05 PM   #33
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QuoteOriginally posted by denisv Quote
I always thought it had to do with the sensor heating up or something, but with the release of the 5DII and D90 that shoot video by keeping the shutter open and sampling, I've come up with the question why do DLSRs still have mechanical shutters?

Why not just flip up the mirror and sample the sensor electronically on exposure? It'd allow lighter, smaller, quieter, more reliable cameras and faster "shutter speeds" (1/250000 anyone?).
There are several reasons, but the most important one (to me) is:

Electronic shutters generate switching noise, which raises the noise floor even higher as ISO increases. Mechanical shutters do not contribute to sensor noise.
04-06-2009, 12:00 AM   #34
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You cant prevent a light sensitive device from generating electricity unless you block out the light. Without a mechanical shutter the sensor would be generating a signal constantly....

Could use that to charge the battery maybe

04-06-2009, 12:55 AM   #35
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QuoteOriginally posted by WerTicus Quote
You cant prevent a light sensitive device from generating electricity unless you block out the light. Without a mechanical shutter the sensor would be generating a signal constantly....
Not really.

We can prevent a light sensitive device from generating electricity when the power supplied to it is cut !

As such, switching on and off the power supply to the imager can do the electronic shutter, but of course there are side effects and limitations, too.

QuoteQuote:
Could use that to charge the battery maybe
Ricoh had a SLR called XR-S which used solar energy to power the light meter. But since the solar generates only weak power, it can by no means drive a power hungry monster like a DSLR. XR-S is a mechanical SLR, IIRC, there is even no electronic controlled shutter.
04-06-2009, 05:06 AM   #36
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QuoteOriginally posted by RiceHigh Quote
I don't think there is any "single blade" mechanical shutter on Earth for use in any DSLR/SLR.
It is stated so, in the DPr specs sheet.

And Nikon themselves say :
"Single-blade mechanical shutter provided for smear prevention"
The Nikon D1

But if it is a typo, and it really acts more like the D1x, it doesn't matter much to me
04-06-2009, 05:34 AM   #37
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QuoteOriginally posted by Jonson PL Quote
It is stated so, in the DPr specs sheet.

And Nikon themselves say :
"Single-blade mechanical shutter provided for smear prevention"
The Nikon D1

But if it is a typo, and it really acts more like the D1x, it doesn't matter much to me
There are at least two blades for a mechanical shutter to work: one in front and the other behind.
04-06-2009, 07:52 AM   #38
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QuoteOriginally posted by RiceHigh Quote
There are at least two blades for a mechanical shutter to work: one in front and the other behind.
Unless the shutter is circular...

04-06-2009, 09:27 AM   #39
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I wonder if I could stand that OP's question on its head and ask, how is it that high-end compact, fixed-lens cameras manage to take such good photos WITHOUT a mechanical shutter?

Will
04-06-2009, 11:34 AM   #40
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QuoteOriginally posted by WMBP Quote
I wonder if I could stand that OP's question on its head and ask, how is it that high-end compact, fixed-lens cameras manage to take such good photos WITHOUT a mechanical shutter?

Will
They most likely are using a leaf shutter.
04-06-2009, 03:39 PM   #41
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QuoteOriginally posted by WMBP Quote
I wonder if I could stand that OP's question on its head and ask, how is it that high-end compact, fixed-lens cameras manage to take such good photos WITHOUT a mechanical shutter?

Will
Those that lack a shutter do have shortcomings when it comes to objects moving at them or perpendicular to them which results in a slow response times.
04-06-2009, 09:16 PM   #42
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In P&S cameras with "Live View" the sequence is:
When the shutter button is depressed partway the image is collected via the sensor (shutter is wide open) and the image is shown on the LCD.
When the camera is told (shutter is activated) to take the picture, focus and exposure are calculated, the shutter (usually a leaf shutter - just like in the old days) closes and the image sensor is "charged". The shutter is opened and the image is sent off to the buffer.

Hence "shutter lag" - yet another reason to dislike "Live View". However, with a SLR - makes not difference whether film or digital - if you see the "perfect" image in the viewfinder - you missed the shot, because the image is captured when the mirror is up and you can't "see" anything.

The Elitist - formerly known as PDL
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