help with Tri X

Hi everyone!!. I have processed six 120 rolls of Trix at 400 ISO in one go with Tmax. I gave a prewash at 20ºc of one min. and I was surprised by the deep purple it came out. Did it allright? or should I leave the prerinse?. I developed 6 min 15 secs in Tmax 1+4 with two brisk invertions every 30 secs, then one minute in kodak stop, and then 10 mins in Agefix at 1+5. This is the dilution Agfa recommends for rapid film fixing. Then 20 mins wash and a final 1 min with filtered water and two drops of Photo flo. The trouble is that I got a silvery slight veil all over the films, even in the outer unexposed parts of the negative. It has a very very slight purple hue. I have tried washing manually some unused parts of one negative but it won´t fade away. Could it be that the fixer didn`t take the unexposed silver salts?, could it be the wetting agent?. Working with 120 in this big tank ( JOBO 1520 pls extension to accomodate three double reels), How should I change developing times?. This is the best forum ever and it is undoubtedly due to the people that so generously help. Thanks indeed to all.

The purple hue is a common theme with Tri-X and T-max negatives and I believe its from the anti-halation layer. Some developers like Rodinal seem to do a good job of stripping away the purple color but most people recommend extending fixing times slightly and washing thouroughly. This is what I do and allthough a very slight purple cast remains it doesn't affect the printing process at all. I'm sure people here with more experience than myself can give you a more thourough answer.

Try a post-fix soak in a solution of 20 to 25 grams per liter sodium sulfite (this is also a good fixer clearing bath, BTW). Then wash the film. That should get rid of most (if not all) of the purple.

The "silvery slight veil" indicates the film was inadequately fixed. Was it fresh? Was it mixed to full film strength?
Try refixing the film and then follow through with processing and washing. A one minute rinse in sodium sulfite prior to washing will shorten your wash time.
The color which came out with the pre-rinse is normal. It is only the anti-halation backing being dissolved away.
Jim

After forty years of commercial photography with Tri-X (and other b&w films) my short advice is: follow the manufacturer's instruction sheets to the letter. Then whatever happens is supposed to happen, and you need not be anxious. It never ceases to amaze me how few people follow those instructions.

More specifically, I like to use Ilford chemicals because of the extremely detailed instuctions on their website: http://www.ilford.com/html/us_english/homeng.html

Regarding your technique in general, Ilford and some others strongly discourage a prewash as it washes away chemicals (the deep purple) put there for a reason. I have never used a prewash on the many thousands of rolls and sheets I have processed.

Not sure why you are using T-Max developer for anything other than T-Max films. D76 or ID-11 are the usual garden-variety soups for Tri-X. Or something more exotic like Rodinal, if you like grain (as I do). Your agitation is fine. People usually over-do it.

One minute in stop bath won't hurt anything, but 30 seconds is enough.

Ten minutes is a very long time in the fixer. Ilford recommends 2 to 5 minutes for their rapid fixer.

Finally, two drops of Photo Flo doesn't sound like quite enough. Isn't the recommended dilution 1 to 200? It used to be something like a capfull in a quart of water. The correct amount will vary with the composition of your water.

None of the above has anything to do with the tint in your negatives. As I said, if it is there, it is most likely supposed to be there. Agfa 25 35mm used to be bright blue when processed. It also bothered lots of people, but did not affect the resulting prints.

Again, I strongly encourage you to take a close look at the Ilford website. Print out those PDF technical product and chemical files, punch them and put them in 3-ring notebooks in your lab. Most importantly: follow their instructions to the letter - not advice from people like me whom you do not know.

I didn't notice that you mentioned you fix for 10 min. I don't know much about agefix but that is quite a long time in the fixer so extending fix times wouldn't be wise in your case. I fix my Tri-x for about 6-7minutes in Kodafix and then use Hypo-Clearing agent. This removes almost all of the purple. Like John said, a very slight purple color is probably unavoidable and is probably engineered into the design of the emulsion.

Fixing times should be three times clearing time and if clearing time is more than a minute - your fixer is shot. Clip a leader of undeveloped film and put it in your fixer. After one minute pull it out - It should be clear - no haze. That is a quick easy fixer test. Over fixiing can cause your shadows to deteriorate - a bad idea. Also - water is great stop bath. The only time I use any kind of "stop" is when working with staining print developers and then I use a VERY WEAK one - one shot. Stop bath can cause more harm that good in a lot of situations. I have found that with an amonium thiosulphate fixer and a ten minute wash - 90% of the film tint will go away. Film tint is likely of no consequence anyway.

John Cook said:

Regarding your technique in general, Ilford and some others strongly discourage a prewash as it washes away chemicals (the deep purple) put there for a reason. I have never used a prewash on the many thousands of rolls and sheets I have processed.

Click to expand...

That isn't exactly accurate. I would hardly consider the following a 'strong' discouragement. From Ilford's Hp5 .pdf:

"A pre-rinse is not recommended as it can lead to uneven processing."

However, if you talk to their technical support, which I have, they consider it a 'general' recommendation. When I mentioned that a prewash eliminates any streaking when using Hp5 sheets in my rotary, they said "Then definately do it."

For Tri-X sheet in trays or large tanks, Kodak says this:

"Prewetting sheet film may improve tray process uniformity."

http://www.kodak.com/global/en/professional/support/techPubs/f4017/f4017.jhtml#small-tank%20processing%20(8-%20or%2016-ounce%20tank)

For roll film, Kodak recommends you drop the film into the developer, so a prewash isn't necessary.

I've never had a problem with a prewash when rotary processing 35mm/120/4x5. It has, definately, eliminated streaking. I've never had a problem with prewashing in a small tank (which I generally did not do), which I rarely use now.

The purple dye is part of the anti-halation coating. Wether it is there or not during processing, from my experience, is moot. Ilford has mentioned that sometimes a prewash can remove wetting agents designed to aid in development. However, I don't have a problem removing their wetting agent and replacing it with mine (distilled water) if I get the benefit of no streaking.

As usual, the best way is to test your own set-up.

"...follow the manufacturer's instruction sheets to the letter."

What a wonderfully radical outlook! Of course, following advice like that will really reduce the traffic on photo message boards.<g>

Neal Wydra

Personally I do fine without prerinse.

"I developed 6 min 15 secs in Tmax 1+4 with two brisk invertions every 30 secs, then one minute in kodak stop, and then 10 mins in Agefix at 1+5. This is the dilution Agfa recommends for rapid film fixing."

Agfa says 3-5 mins fixing at dilution 1:5, so if the fixer is fresh 10 mins will not hurt. For 1520 Jobo + 1530 extension volume is about 1.1 litre. 1 litre of Agefix 1:5 should be fine for 15-20 films. If is just a purple tint do not worry, if it however contains silver than it might be "Dichrotischer Schleier", if the developer is contamined with chemicals which are able to dissolve silver, e.g. fixer, thiocyanate, silver particels get dissolved and can form a "Schleier" a kind of thin film on the surface, which is hard to remove once the film is dry but I think it can be removed with chemicals. However as it is developed silver it can not be removed by simple refixing.

Regards,

Wolfram

The “silvery haze” you specified might be the TXP film base. The “old” TX-400 had a very different base and the “new” TXP-320(?) has always had a “tooth” in the back (non-emulsion) side to aid in (shudder) retouching. Otherwise some additional fixing might be in order. 10 minutes should be quite adequate and more won’t hurt. It takes a really long time for fixer to dissolve sufficient silver to be noticeable (like hours).

Residual color (purple, magenta et c.) in certain films has been a recurring theme in many photo discussions for a long time. I did some practical research to determine the source and it is apparently a dye used in the emulsion as a sensitizer. It is definitely not the antihalation dye which is on the opposite non-emulsion side. This is rather completely decolorized by the developer. It is also the material yielding the color of your pre-rinse – not to worry. Finally, the residual color will be removed in a thorough water soak/rinse especially with HCA or equivalent.