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07-23-2008, 10:24 AM   #16
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QuoteOriginally posted by k100d Quote
what is the conversion factor for 645 lenses to 35mm?
Hi K100D,

There is no conversion factor when using a 645 lens on a 35mm. A 300mm lens is still a 300mm lens. When using a 35mm (or APS-C) body you are only using a smaller center portion of the 645 lens. The "cropping" factor for the APS-C body would be the same @ 1.5%

The difference you are probably thinking of is when using a 300mm lens on a 645 what would be the comparison for a similar setup on a 35mm? In which case you need to compare the angle of view.

The angle of view for an A645-300mm/F4.0 is 13.5 degrees
The angle of view for a F*300mm/F4.5 is 8.2 Degrees

So in approximate terms looking though a 645 with a 300mm would be equivalent to looking through a 35mm with a 185mm lens, in terms of field of view.


07-23-2008, 10:32 AM   #17
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QuoteOriginally posted by MRRiley Quote
if you want to shoot 33 quick shots it'll take you a whole minute (must be german math).
I wonder if this is due to the camera, or the cards write speed.
07-24-2008, 07:59 AM   #18
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QuoteOriginally posted by little laker Quote
I wonder if this is due to the camera, or the cards write speed.
The 1.x frame per second is probably a function of "transfer" speed between the camera and the card... and its actually pretty fast if you think about it... 50mb per sec... not exactly Mr. Slowski...

The 33 frames per minute is probably a buffer issue... That beast would need a HUGE HUGE buffer to handle anything faster.

(just guessing)
07-24-2008, 08:03 AM   #19
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also this is just a total guess

but if you force your user to never shoot faster than X speed, you can maintain a noise level standard and avoid customer complaints because you more or less allow the sensor too cool off for that split second before taking the next shot.


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