Best possible push developer recipe?

Kino

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If you have no underlying issues with abnormal movement, run at 8fps or even 4 fps to gain one or two stops. Locked-off on a tripod, of course...

(Assuming you are running at 16-18 fps as most amateur cameras do.)
 
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bendytwin

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Kino said:
If you have no underlying issues with abnormal movement, run at 8fps or even 4 fps to gain one or two stops. Locked-off on a tripod, of course...

(Assuming you are running at 16-18 fps as most amateur cameras do.)
Click to expand...

Thank you for the suggestion -- this was on a REX bolex that only goes down to 12fps without an intervalometer. Non-reflex models of course have a slightly larger shutter angle (resulting in ~1/45th exposure time at 24fps) and no light loss to the reflex prism. Critical framing is harder work with the side finder, but you're right that the extra light would ahve been very helpful. I almost never use slow motion but like doing short time lapses and have contemplated modifying the speed governor to bias toward much lower speed in order to acheive 8/4/2fps on a reflex, then just moving the dial to correlate with the new 24.
 

Paul Howell

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Well as it turns out Acutance can be measured. My 1963 edition of The Encyclopedia of Photography Vol 1, page 70 to measure acutance a picture of sharp blade is taken then using a microdensitometer changes in density along the edage of the blade is taken a graph developed and single number is provided. The article is short and did not give a range of numbers and stated that film and lens manufactures do no release results.
 

Kino

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bendytwin said:
I almost never use slow motion but like doing short time lapses and have contemplated modifying the speed governor to bias toward much lower speed in order to acheive 8/4/2fps on a reflex, then just moving the dial to correlate with the new 24.
Click to expand...

That would actually be fast motion; slower shooting speed = accelerated subject speed on playback and vice-versa, but I understand what you are saying.

I would rather hack an intervalometer motor setup to get to the lower speeds than mess with the integral Bolex governor. Those can be quite easy to mess-up and get uneven spring speeds, IMHO. The intervalometer motor can be removed easily but a failed modification can put you on the sidelines.

Good luck!
 
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