Anything between Xtol & FX-39

[Alan Johnson]

I only have FX-37 but Crawley has said this is the nearest published formula to FX-39.My pH paper shows:
Xtol 1+0 pH just over 8
FX-37 1+3 pH about 10
Mixture equal volumes Xtol 1+0 and FX-37 1+3 has pH about 9
What you see may be simple pH effect, not alchemy.

 

[Tom Stanworth]

I only have FX-37 but Crawley has said this is the nearest published formula to FX-39.My pH paper shows:
Xtol 1+0 pH just over 8
FX-37 1+3 pH about 10
Mixture equal volumes Xtol 1+0 and FX-37 1+3 has pH about 9
What you see may be simple pH effect, not alchemy.

Sure, but the two developers have different development agents as well if my memory serves correctly. I guess superadditivity falls into the alchemy category unless one has rather good knowledge of chemistry and even then it might not be clear. It was the potential for strange interaction of various chemicals that was the concern with mixing these two developers, but ti appears that this is not the case with these two.

I would rather mix Xtol and FX-39 together to change the pH (if this is responsible) than mess about with other chemicals, as I do not have scales here, reliable storage etc and I sure as hell dont want to be going thru Kabul airport with white powders in baggies

Those Neopan fX-39 negs are sooooo crisp but smooth skies are not their forte. Xtol is just too lacking in edge for me. If mixing the two gives a good balance I will consider myself very lucky. In all probability some balance of chemicals somewhere will be upset and it will lean one way or the other. However, thus far, it looks to lean more towards FX-39 than Xtol. Definitely more crisp than Xtol alone.

 

[Tom Stanworth]

Well, I have just looked at the first roll of Neopan 400 with the two devs mixed. The negs are a touch undeveloped, but not by much. Comparing areas of equal visual density (I had some well matched skies), it is clear that the grain is less than FX-39 alone and less sharp, but a little more crisp than Xtol 1+1 and slightly grainier. It appears, based on very casual testing I admit, that the mixing of these two does indeed produce results about between the two. Dev times and film speed remain constant, although I will test again and check for density as it appears that this test roll was about 10 % under developed. That can occur with the temperature fluctuations in the rooms I use, which can result in convoluted measures to cool water down using the AC unit and then development taking place in a far warmer room (which I cannot get below 26 degs no matter what!). I was also rushing; however, the equally dense smooth skies tell no lies! They are about the same density so the 10X loupe test should me moderately insightful when comparing similar densities.

The mix produces good negs and I really cannot see any problems with mixing these two devs. I will reserve final judgement until I get to print identical test negs, however. I am hugely excited as this could be my perfect solution for full Xtol/FX-39 speed with TriX/Neopan 400 with more bite than Xtol and smoother grain than FX-39! I really expected this to fail miserably.

I will probably experiment further using a test clip which I will insert at the tail end of other rolls when I do Xtol and FX39 development. I will then do a third clip with the two devs mixed.

 

[Tom Stanworth]

I have spent 30 mins staring at various negs under a loupe and can say with moderate confidence that pairing these two developers gives fantastic looking negs - I have not printed them but just cannot see any problem at all. They grain is not that much larger than Xtol 1+1 but more clearly defined and more crisp and it is very noticeably finer than FX-39 1+9 on Neopan 400. There is more contrast within the grain pattern with the mixed dev negs (as one sees with FX-39) under a loupe rather than the reduced contrast one see within the grain pattern of Xtol negs. Looking back over dev times and temps I gave a little under the development I intended to give (but still, I compared like density with like). So it would seem that using these two devs allows you to use pretty much the same film speed with both, or the two mixed and get varying acutance and fineness of grain between Xtol 1+1, the two mixed and FX-39 alone. I am a very happy bunny. I guess this means one could treat is like a continuum if one wanted getting a sliding scale between them, but I wont go that far. I find dev times a little shorter for FX-39 than xtol 1+1, but not a huge amount so even the dev times are in a similar ball park. I see the mixed devs being very handy for new TriX and Neopan, both of which become rather soft and all too smooth for me in Xtol 1+1, for gritty scenes.

 

[Steve Smith]

Give it a go - what's the worst thing that could happen?

Obvious the worst thing that happened was that you got negatives that you liked the look of!


Steve.