Does This Sentence Make Sense To You?

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Norseman
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Does This Sentence Make Sense To You?

Post by Norseman »

From the Bolex Zoom Reflex P1 Manual, under "Use of the Variable Shutter":

"When filming with the shutter half closed, set the exposure dial to a number half the speed of your film expressed in ASA, or the double number of the filming speed."

I want to film some moving subjects in slow motion, at film speed 64. They say if you close the shutter half way, you will increase picture sharpness. The film I'm using is Cine Chrome 40 ASA 40 Tungsten ( I'm using a #85 filter for daylight, but the manual says NOT to set your exposure index dial to 25 beacuse the photo-electric cell compensates for the light lost through the filter). So, if my film speed dial is set at 64, and my shutter is half closed, what do I set the exposure dial at? Thanks for your help.
Norseman
reedsturtevant
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Post by reedsturtevant »

if my film speed dial is set at 64, and my shutter is half closed, what do I set the exposure dial at?
My guess is set your fps to 128 (if you can) or your ASA to 20.

The 1/2 open shutter means you need twice as much exposure (one stop wider aperture), just as you would for a faster frames-per-second or a slower ASA. Does that make sense?
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