How to measure 35mm film length in dark

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milesandjules
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How to measure 35mm film length in dark

Post by milesandjules » Thu Jun 14, 2018 2:31 pm

Hi I need to accuratly chop a 400ft roll of 35mm in half as we only have a 200ft mag on our eclair 😩 what’s the best way to do this - it’s going on a core - cheers miles

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MovieStuff
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Re: How to measure 35mm film length in dark

Post by MovieStuff » Thu Jun 14, 2018 3:08 pm

I assume it is on a core. If you have some other already processed film, either 35mm or 16mm, you could put 200 feet of that processed film on another core and then temporarily put that loaded core on the intended split reel. This can obviously all be done in daylight. Just make sure that the 16mm core is the same diameter as the 35mm core. If not, then use a 35mm core with the 16mm film just for accurate measurement purposes. Once you have wound 200 feet onto the split reel, take a piece of tape and attach to the outside of the reel so the edge of the tape aligns with the outer edge of the 200 foot wrap. Now you have something you can feel with your fingers in the dark that will tell you when to stop winding. Use that same split reel to wind your 35mm film onto until you can feel the wrap of the film reach the same point on the split reel as the edge of the tape.

Roger

Mmechanic
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Re: How to measure 35mm film length in dark

Post by Mmechanic » Fri Jun 15, 2018 7:28 am

You use a synch roller with a counter whose cyphers are painted over with phosphorescing paint. You can also install a lighttight funnel with a little bulb or a LED inside to peep in or a contact switch in conjunction with an electronic counter so installed that its light doesn’t reach the film. Maybe a Nixie-tubes display

milesandjules
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Re: How to measure 35mm film length in dark

Post by milesandjules » Tue Jun 19, 2018 12:43 pm

Thanks guys 👍

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