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Best developer to achieve highest ISO with Tri-X

Xmas

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And separating spectral lines in star astronomy for the same reason.
If you want night shots with lights in scene then POTA will capture most data, printing may be more difficult there by.
Mixing a different technique may leave the worst combination rather than a better one.
There are some variants of POTA in addition to the APUG specials linked to in above post.
 

Athiril

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Regardless of the developer, a hard push and pre-flash will get far more out of it.

Superia 800 @ 12800 example, I based it on an article about pre-flashing for Tri-X.

no preflash + push
Superia 800 @ 12800 no preflash by Daniel Lee, on Flickr

preflash + push
Superia 800 @ 12800 Zone 3 preflash by Daniel Lee, on Flickr









In regards to POTA, a long push in it might work very well, will stay thin low contrast, but bleaching and re-developing in a colour developer with colour coupler many times over is supposed to gain more stops of speed normally unattainable. Probably out of the realm of practicality for your student though. Pre-flash remains practical.
 

Mike Crawford

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Thinking about it, it did have a replenisher, so we would have topped it up. As I remember, (and this is 30 years ago!), it lasted a while in the small deep tank. It looked disgusting with loads of crap floating about but seemed to work fine.
 
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David Allen

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Very impressive results Daniel.

I used to sometimes use a pre-flash when I did large format landscape photography (for contrast control) - but that was some 30+ years ago.

I would appreciate it if you outline your pre-flash technique - would be very interesting and helpful.

Bests,

David.
www.dsallen.de
 

Athiril

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The difference in shadow detail is mild at best (even if pictorial exposure is under exposed) in normal processing times but very significant with a very hard push.

I used an AE-1, which meters through the lens, the film used was Superia XTRA 800, I did pre-flash via double exposure. So I had a double tissue folded and held over the lens and exposure, pushed the rewind button and held the rewind spool firm while gently advancing the film advance lever so I could go to next shot without advancing the film.

Pre-flash that worked was 6 stops under box speed (so metered at 800, counted 6 stops less exposure) the average 18% grey reading through the diffusing material (the meter would take into account anything over the lens since it's TTL metering). Anything less than that had no effect. - Doing it like this via double exposure lets you use and compare different pre-flash amounts and no pre-flash easily too.

First roll you may need a test roll, but its probably in the same vicinity, you could shoot Tri-X at 6400 with a lot more shadow detail this way.


Read it about Tri-X here, then applied to Superia 800, so should apply to Tri-X no worries.
http://www.strobist.blogspot.com.au/2013/02/how-we-got-here-analog-photoshop.html