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04-21-2007, 02:54 AM   #46
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measurebation

How can you not know what that means? I've been doing it since I was about 10!

04-21-2007, 03:08 AM   #47
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Oh, my pal, who have ever mentioned about the "shutter speed" in this thread? :-)

To put it short, the mirror CANNOT go down before the shutter is opened (and closed after opened), can it?

So, if the shutter lag is longer (the shutter lag *is* the time delay after the shutter release button is pressed and the shutter finally opens!), the finder black out time must be longer - no doubt here!

QuoteOriginally posted by PDL Quote
OK - You do not "get it".
The time it takes for the mirror to go up - and the time it takes to return is constant regardless of the shutter speed. The only variable is the amount of time the shutter takes for those times when the blades of the shutter expose the entire sensor.
These cameras use vertical focal plane mechanisms - the blades of the shutter move at the same speed regardless of overall shutter speed. At low speed the first blades (there are three I believe - at least there are three on my SF1) open and the last blade moves at the end of the cycle to cover the shutter - and at what maximum shutter speed is the entire sensor exposed? 1/180 of a second - X sync speeds. That is how focal plane shutters have worked for the last century - maybe you should do a little research - eh?

At shutter speeds over 1/180th of a second the exposure is made as the shutter blades are best describes as creating a slit moving across the sensor (and in this case it is the same in film or digital). So how long does it take the shutter blade to move across the sensor - no longer than the fastest shutter speed say 1/4000 of a second? The actual time it takes to expose a 1/200 or 1/3000 of a second image is about the same in absolute time from mirror movement to mirror back down - that is because the exposure is defined by the distance between the shutter blades as they move across the sensor.

The time of "black out" is constant once the shutter speed is above 1/180th of a second. Shutter lag - as discussed here - is the amount of time between pushing the shutter button to when you "hear" the shutter fire. As I said - if you can "hear" the difference - then your hearing is better than a dogs. As for the C*non 20D and the new one - the overall mirror up to mirror down will be shorter - because their FPS is higher. But to define this as "shutter lag" is not correct.

PDL
04-21-2007, 03:11 AM   #48
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QuoteOriginally posted by Christian Quote
How can you not know what that means? I've been doing it since I was about 10!
So early? ;-)
04-21-2007, 06:52 AM   #49
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To be honest I can't remember...

04-21-2007, 05:26 PM   #50
PDL
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RH - geesh this is frustrating.
The mirror movement you know up and down - is constant. The longer black out - as you mention over an over - due to mirror movement. The discussion was about SHUTTER LAG - get it?
Now the OP says he was just talking about the "sound" not anything physical. Longer periods of mirror up (Longer black out - your term) are due to shutter speed being slower than 1/180 of a second on the K10D. Just go off and do a little research on how focal plane shutters work. The shutter starts electronically - controlled by the camera - not physically - when the shutter completes the exposure then the mirror drops back into postion - however the time it takes the mirror to move up and move down are the same. If the "black out time" is different it is beacuse of the shutter speed. ---- just go look it up.
PDL
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