tmax developer dilution ratios?

[tallaght_spur]

hi all im looking to extend the life of my tmax developer. i have been using the

recomended 1x4 dilution but have read that it is possible to mix it at 1x7 and

even 1x9 ratios. Is this true and if so could someone please explain the

development process re: time and temp for these ratios. i use ilford hp5 400iso,

also if it could be clarified if i can use this developer repeatedly as up to

know i have been using once (1x4 ratio) and disposing of it once used.

Thanks in advance

[William Kahn]

Kodak's recommend dilution/development times are here (for TMax films, small tank processing):

 

http://www.kodak.com/global/en/professional/support/techPubs/f4016/f4016.jhtml#small-tankprocessing(8-or16-ouncetank)?rolls

[mattalofs]

You can reuse Tmax diluted at 1+4. There's time adjustment directions on th bottle for repeated uses.

 

I've had good luck using Tmax diluted to 1+5 and 1+9 to help control contrast. For HP5, I've found that 4.5 minutes works well for Tmax diluted 1+5 at 75 degrees. Agitate for 5 seconds every thirty. For 1+9, just double the time.<div></div>

[Rob F.]

I've used TMax at 1:7, but I consider it a one-shot at that dilution. It's half-strength, just as D-76 at 1:1 is half-strength. I wouldn't expect it to keep. I'm not sure if there would be enough developing agent left at 1:7 to do another roll. At 1:9, it would seem even more questionable.

[jeff_schraeder1]

I have used a 1-9 ratio TMax RS for years, one shot of course. I use times of around 10 minutes at 75 degrees. It would be a good place to start calibrating. I use the same dilution on 35mm (Tmax 400) 120 (Tmax 400) 4x5 (Tmax 100) and 8x10 (Tmax 100). It keeps things simple.

[alan_rockwood]

Phototherm recommends using T-Max developer at 1:5 dilution in their processing machines. In fact, it is the only developer and dilution for which they give recommended processing times. Here is a link to Phototherm's recommended processing times. Note that most of the times are for 75 degree F temperature.

 

http://www.phototherm.com/sktech/second.html#bw

 

Phototherm is a rotary processor, so it has continuous agitation and one can expect their processing times to be shorter than processing by hand with intermittent agitation. I imagine that other rotary processors (Jobo, Unicolor, etc.) could use development times and temperatures similar to Phototherm if one were to dispense with the pre-soak step that Jobo normally recommends.

 

Here is another link to phototherm containing additional information.

 

http://www.phototherm.com/

 

 

Phototherm processors sometimes come up for sale on ebay. In my opinion Phototherm equipment is much easier to use than Jobo, and the build quality is much higher as well. However, Phototherm is less flexible than Jobo's equipment because the programming options are somewhat limited and Phototherm only develops film, not paper. If you decide to get a phototherm the Super SideKick models are are preferred over the older SideKick and FP-1 models because the Super SideKick has more programming options than the older models. However, the older models at least let you change the developing time, so they can handle most film developing tasks such as push or pull processing.

 

By the way, Phototherm units usually also come pre-programmed for E-6 and C41 as well as B&W, which is a nice feature.

 

Sorry for bending this thread over to a discussion of rotary processors and Phototherm processors. It just seemed to naturally drift from T-Max developer to rotary processors.

[alan_rockwood]

Oops, one more thought. I just realized that what you really want to do is extend the life of your T-Max developer. Phototherm's recommendations are for one-shot development, but at least at a slightly higher dilution you are saving a little money. I understand that HC-110 and Rodinal are very inexpensive to use if one uses the higher dilutions, and in that case one-shot development becomes attractive. The concentrated developers HC-110 and Rodinal solutions also have very long shelf life, especially Rodinal, which is legendary in that regard. Have you considered using either of those developers.

[tallaght_spur]

thanks for the replys so far folkes. i have 60+ students who are all using ilford hp5 400 iso and using small hand held tanks. Ive searched and i cant seem to find any recomended dev times for such film using TMAX at the 1:9 ratio...

[robert_grasing]

Kodak says the 1+9 dilution is OK with 100TMax and 400TMax, even with a small (237ml) tank, so it should be alright with HP5. No times for HP5 or even Tri-X, but they should be between 2 and 2.5 times your 1+4 times. Kodak does not recommend diluting beyond 1+9 because of increased graininess. I think you will probably see a grainier but slightly sharper image at 1+9 than you get with 1+4. There should also be a slight film speed increase, perhaps 1/3stop.

[peter_fitzsimons]

I use it at 1:7 with Tri-X but did the zone 8 development test first to determine my dev times. For consistancy I only use it one shot.

 

Peter