8mm Forum: Hand crank bolex

This is topic Hand crank bolex in forum 16mm Forum at 8mm Forum.

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Posted by Louis Li (Member # 776) on February 23, 2007, 11:36 PM:

Has anyone here tried hand cranking a bolex?
Cranking using the little backwind crank for double exposures.

im trying to figure how fast i have to crank in order to get a decent exposure.

Posted by John Whittle (Member # 22) on March 05, 2007, 03:54 PM:

There are two hand crank shafts on some (but not all) bolex cameras. Most all have the 8 frame shaft (that would be 3 revolutions per second) and the later Rex cameras have a single frame shaft (which was used for motor drives).

Using the bolex supplied crank, you'll have a bit of difficulty in trying to hand crank the camera. Most professional 35mm hand cranked cameras (like the Bell & Howell 2709) moved half a foot (eight frames) per revolution and the cranks were much larger and gave you more leverage and a wider circle to operate.

You'll have to calculate your own shutter speed based on your cranking ability remembering that the shutter speed was (I think and this is from memory) 1/48 of a second at 24 fps (and you had to adjust it for light loss for the prism if you have a Rex camera).

John

Posted by Louis Li (Member # 776) on March 31, 2007, 12:13 PM:

im sorry this took a while. almost too long. But thank you john.

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