Crawley's FX-37 Developer for T-Max/Delta Films

[Gerald Koch]

This developer is intended for use with T-Max and Delta films, although it will produce excellent results with traditional emulsions. FX-37 is designed to produce very sharp, tonally rich negatives with an EFS speed increase. It is not a fine grain developer and is not recommended for fast traditional films.

Increase the EFS by one-half to two-thirds of a stop.

Distilled water (50°C) ................. 750 ml
Sodium sulfite (anhy) .................. 60.0 g
Hydroquinone ........................... 5.0 g
Sodium carbonate (anhy) ................ 5.0 g
Phenidone .............................. 0.5 g
Borax .................................. 2.5 g
Potassium bromide ...................... 0.5 g
Benzotriazole, 1% ...................... 5.0 ml
Distilled water to make ................ 1.0 l

All times are for the 1+3 dilution at 20 C. For increase speed dilute 1+5.


—————————————— EI — Min —————
Fuji Neopan 400 500 6
Neopan 1600 1600 5
—————————————————————
Ilford Delta 100 160 8¼
Delta 400 500 7½
Pan-F Plus 64 4
FP4 Plus 160 4½
HP5 Plus 640 6½
—————————————————————
Kodak Plux-X 200 5½
T-Max 100 Pro 125 8
T-Max 400 Pro 500 9
T-Max 400 Pro 400 8
T-Max 3200 1600 8
Tri-X 500 6


Crawley stated that FX-37 is the closest published formula to FX-39

The benzotriazole can be eliminated if the bromide is increase to 1 g/l.

I have not tried this formula as I do not use either of the two classes of film mentioned. I include it here because some people do like these films.

[Sean]

Comments from previous article system:

By Rlibersky - 11:39 AM, 07-20-2006 Edit Rating: None
I have used this formula with Plus-x @100ASA, Bergger @100ASA and Ilford 3200 @1600 with excellent results. Especially with the Ilford 3200. The finest grain I've seen.
By aligndont - 07:20 PM, 09-02-2006 Edit Rating: None
I've notice that if you use this developer at 24c and alter developing times as per time/temp converter in massive developing page then you have an exceedingly sharp fine grain developer.
By craigclu - 05:41 AM, 09-04-2006 Edit Rating: None
I've finally been getting at some testing for a speed enhancing (or at least attaining rated ISO's) developer. I tested a few things in this today and was pleasantly surprised at the fine grain, too. I got slightly over-developed results with the above times/temps and likely will try moving to 1:5 and see what the grain looks like and get more controllable times. Is anyone else using this and can share some results?
By Rob Archer - 06:03 PM, 09-13-2006 Edit Rating: None
How important is it to use distilled water - if so why? (i'm not a chemist!)

Rob
By Gerald Koch - 06:15 PM, 09-13-2006 Edit Rating: None
The formula, as published, does not contain any calcium chelating agent. Attempting to add one may throw the pH of the solution off. I recommend using distilled water for all stock solutions of any developer and in this case also for the working solution.

The calcium hardness in tap water can precipitate out onto the film surface as a whitish scum. Using distilled water prevents this.
By pauldc - 07:30 PM, 09-13-2006 Edit Rating: None
How do you convert the suggested times from 1:3 to 1:5? I have just made some FX-37 up and am ready to give it a go with Pan F. Also, are there advantages to grain size in going to the 1:5 dilution? And I am assuming that 1:5 means 1 part developer to 5 parts water. Cheers, Paul
By Gerald Koch - 07:59 PM, 09-13-2006 Edit Rating: None
I would try 1.5 times the 1+3 times.

As with most developers of this type, the greater dilution should produce increased acutance with a slight increase in grain.

BTW, I actually listed the dilutions as 1+3 and 1+5 to avoid use of the rather ambiguous colon notation such as 1:3.

[Alan Johnson]

Geoffrey Crawley wrote (Amateur Photographer 17 Feb 07) to the effect that the sharpness of FX-37 is the result of the combination of borax and carbonate as alkalis.The carbonate beefs up the the softness given by the borax without a noticeable increase in grain.This is helped by the milder solvent effect of the reduced sulfite content.The formula could be described as a "sharpened-up" D76 with phenidone instead of metol.

[Peter De Smidt]

I've used a little of this developer, and it worked fine. I don't buy the speed increase, though. If there is one over comparably dilute D76, it is negligible, as in less than 1/3 stop. At least that was the case in my system with the films I tried, TMX and TMY.

[eclarke]

I have been using this stuff at 1+5, 68° F. to develop Tmax 100.. I just love it, sharp with good gradation, economical and the stock keeps very well..Evan Clarke