Reducing contrast of film during development.

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Oh! Sloppy test shots caused me to rate my tech Pan 120 film at ISO32. Now I realise this is going to give me too high contrast for my subject (high contrast anyhow to start with). I've run another Tech Pan film off and done some dev testing with a two stepper (emofin) but still too high contrast. I'd like to know how effective a water bath would be with this developer and weather I'd get any blotching occurring. Or would you expect Technidol to be the only way forward. Then again anybody tried a water bath with Technidol? If anybody could help me with a visualisation here: if you had one neg developed 'normally' and one in Technidol what would the contrast difference be if likened to that of b/w paper contrast grades? 5 -to 00 or just 2 to 3? Get the idea? Oh why didn't I shoot more films off...remember people film is cheap. Damn! :o(

Bri

-- Brian Thomas (brit@bwphoto.freeserve.co.uk), August 26, 2000

Answers

if contrast is going to be a problem,use a more consistent and easier film, agfa apx 25 developed in agfa rodinal 1:25 for 6 minutes. it will suit your needs fine. if you really want a lower contrast,for your prints then use tetenal centrabrom-s WWW.FOTOARTE.NET

-- sean anderson (fotoarte@katamail.com), October 05, 2000.

I don't know if you can save it, rated at 32. You might try a pyrocatechin compensating formula. Adams gives one in The Negative. I'd suggest doing a test strip first. Normally they recommend overexposing the film with this formula--instead, your film is underexposed, and Tech Pan is already too contrasty. But your only hope is to develop the heck out of it in a formula that won't overdevelop the highlights.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), October 07, 2000.

Here's a weird idea: try Rodinol at 200:1 for 9 minutes.

-- mathew morgan (morganphoto@msn.com), January 21, 2001.

I'm sorry this is probably too late, but... A number of possible solutions (bad accidental pun) suggest themselves: i) An EI of 32 isn't too far from 25; a fraction of a stop. Ignore the problem. This is probably the easiest, but if you have a long subject contrast range, which with Tech Pan's high contrast is a problem anyway, you will loose the shadows. ii) Some form of compensating dev. As you want, say, a third of a stop extra speed, Paterson FX39 at max dilution would be good, although you might not find enough compensation from that and might not like the gradation, but, boy, would it be sharp! If FX39 isn't locally available, the formula for FX37 is published (and some of the other FXs) are published so you could make them up yourself. The key point here is an 'accutance' formulation. One of the ones that gives 1/3 to 2/3 of a stop speed increase when used at a high dilution and use it at its highest dilution, so it will give some compensating effect. iii) Water bathing sounds promising, but with any POTA-style formulation (Technidol and one of the Neofins {Blue, is it?}), you have the risk of streaking. iv) Most of the staining devs tend to loose a little film speed so that is probably not a good idea. Pushing Tech Pan to overcome the speed loss will probably only make the contrast problem worse. Otherwise, this would be a good idea. v) Paterson FX50 sounds as if it might work, but my local supplier can't get any. vi) There is a suggestion that you can dev Tech Pan in C41 dev., and get an EI of 50-64. Now I haven't tried this, but if the shots weren't too valuable, I'd be tempted to drop the dev time from, I think, 10 mins, to say 8 mins and see what happened. Not seen any negs processed this way, so that has to be experimental.

So my favourite options would be FX 39 or C41 dev depending on how valuable the negs were. FX39 if I thought that I *must* get a printable result, C41 if I felt 'I've screwed up, how much worse can it get'.

-- Mark Wyatt (markw@myworldmail.com), November 22, 2001.


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