Best possible push developer recipe?

[Kino]

OK, thank you.

After making it most of the way through a rather enjoyable 24-page read on the "New HC-110 Formula" thread from last year, I've ordered a liter of the new stuff from B&H to give it a try with super soup.

In the meantime, it had been a decade since I'd pushed Tri-X in Xtol more than a stop, so I mixed up 10L stock fresh today today and tried developing 2x100ft rolls of Tri-X pushed 3 stops to 1250 (artificial light from windows at night). The first roll I did 35min at 68.5F, Xtol 1:3.4 (dilution error on my part), bucket dev by inspection under night vision. The next roll must have been even more poorly exposed (checking my notes from the night of shooting I'm not sure how -- I've not had good luck with Tri-X pushed under artificial light), since it was still extremely thin even after 37min at 72F Xtol 1:2 (so warmer and stronger concentration).

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.)

 

[bendytwin]

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.)

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]

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]

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.

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!