XTOL Replenished for TMAX 400, JOBO Rotary anybody?

[Thomas Greutmann]

Hello,
I shoot mostly TMAX 400 and do my development in XTOL, using Jobo 2500 tubes with Rotary Processing. I have seen quite a few posts in this and other forums saying that XTOL will work even better when replenished and I would like to give it a try.

However Kodak does not publish any development times for this particular combination (table entries are blank), and I have seen a post saying that replenishing and Jobo rotary processing does not work together, no reason given.

Does anybody have experience with this particular combination and would be willing to share their experience? Any hint on development times or replenishment quantities?

Thanks in advance

[jeroldharter]

That is a problem with replenishment systems: how do you test for development times? I don't see the point with a Jobo. If I were using tanks with large volumes then I might use replenishment for economical and practical reasons, but one shot developers are the way to go with a Jobo.l

[Peter De Smidt]

You'd have to get the system stabilized by running a fair number of films before running tests. This would be a great use of really expired film.

My guess is that replenishment will cause bromide (a restrainer) to increase over what's in fresh developer. This should require slightly lengthened development times. Perhaps 10%?

[Jay DeFehr]

Jerold,

I don't understand your question, "how do you test for development times?". How would replenishment change the way one tests for development? One shot developers certainly simplify things, but that doesn't necessarily mean they produce better results or economy. If one's process is in control, replenished systems can be very consistent and very economical. Once your system is started and in control, the replenishment rate (70ml/liter) is all one uses for each roll/sheet of film developed.

Thomas,

Kodak mentions in Tech Pub J109, "Some rotary processors allow the use of replenished developer, see Replenishment." I think the times given for sheet film in a replenished system provide a starting point for personal testing. For TMY-2.

The challenge of a replenished system is in monitoring and maintenance.

http://www.kodak.com/global/plugins/...uals/z-133.pdf

The above provides a good overview of the principles and practice of process control and monitoring.

[tgtaylor]

However Kodak does not publish any development times for this particular combination (table entries are blank), and I have seen a post saying that replenishing and Jobo rotary processing does not work together, no reason given.

Thanks in advance

The most logical reason would seem to be the amount of oxygen that rotary processing introduces into the developer. After several minutes of rotary processing the developer (and fix) is pretty well 'aired-out' and I imagine that all the molecules have an oxygen attached to its receptor.

That said, I have no experience using Xtol replenished. I use Xtol 1:1, 1:2, and 1:3 one-shot in a Jobo and to "capacity" in dip n dunk tanks.

BTW, I wouldn't recommend a water soak prior to processing unless you compensate for it by reducing the development time.

Thomas

[jeroldharter]

Jerold,

I don't understand your question, "how do you test for development times?". How would replenishment change the way one tests for development? One shot developers certainly simplify things, but that doesn't necessarily mean they produce better results or economy. If one's process is in control, replenished systems can be very consistent and very economical. Once your system is started and in control, the replenishment rate (70ml/liter) is all one uses for each roll/sheet of film developed.
...

I understand what you mean. I am sure it is possible to calibrate a replenished system. If I ran a lab and processed a lot of film daily, it might have appeal. However, testing is tedious and time consuming. Processing 5 runs of film through a Jobo for BTZS testing, then running them through a densitometer, etc. is not Herculean but it easily eats up half a day. (One instance in which BTZS tubes are faster than Jobo drums is testing.) So the only way you can confirm that development is consistent in a replenished system it to run tests at various degrees of replenishment. So you would have to run many sheets of film through in between tests, then repeat the tests at points x/y/z and then compare the test results. What if the testing shows some inconsistency? Is it the testing itself? Is it the replenishment rate? Is it temperature variation between runs? Is it...? It just seems needlessly complicated and time consuming.

[Jay DeFehr]

Jerold,

Check out the link I posted for the Kodak process control system. Testing the system is done with process control strips. Film testing is done separately. One doesn't use BTZS testing to test one's process. I agree that maintaining a replenished process is more time consuming than using a one-shot developer, but nothing like as complicated as you describe above. In the end, it comes down to results. If one prefers the results obtainable by the use of a replenished system, I think the effort to maintain one is justified, and not too much of a burden. It's certainly more practical for those who process regularly than for those who process only occasionally, with long gaps in between. Because of my work schedule, my processing is regular, with a fairly high volume for 3 weeks, and then very minimal for the next three, on a rotating basis. Lately I've been using a superfine grain developer of my own formulation, in a replenished system. When I begin my 3 weeks of processing, I test to see where the process is in regard to aim values, and adjust as needed. Since I'm using a relatively low volume of working developer, adjustments take effect almost instantly, and I can get on with processing. Over the three weeks that follow, I test my system after every 5 rolls of film are processed, which would be overkill for an established developer, like Xtol, but useful for evaluating my own developer formula.

Maintaining a replenished system involves a learning curve, but once one gets comfortable with the process, it provides much peace of mind, knowing one's process is in control, and one's results consistent and predictable.

Using a developer like Xtol, D-76, etc., one shot is not as dead consistent as many like to imagine. Every time one mixes up a working solution, several opportunities for error arise. As the stock solution is used, the ratio of remaining developer volume to exposure to air increases, along with the duration of the exposure, making the last working solution potentially much different than the first mixed from a given stock solution. Then there's the potential for contamination, or water quality differences, or measurement errors, or some combination of the above. Certainly, a more stable and concentrated stock solution minimizes these problems, but it won't eliminate them completely. I guess my point is that there's no free lunch, and consistency requires diligence, whatever system one employs.

[Mark Barendt]

You will probably add about 10% to your normal full strength time once you are fully seasoned.

Seasoning depends on how big your working solution bottle is. My bottle is 1.75 liters and it took about 12 rolls to get fully seasoned and stable, 1-liter probably 8 rolls.

It has been absolutely stable and reliable ever since I finished seasoning.

During the seasoning process, the time stretches out gently, probably about 1% extra time for each roll completed.

During the seasoning just top up the working bottle to keep it completely full, might take 10ml or so per roll.

Once you have run your 8-12 rolls start the "bleed". Pour a full 70 ml of fresh Xtol into the working solution bottle for each roll you process then pour the "used" Xtol in until the bottle overflows, discard the rest.

[Sirius Glass]

That is a problem with replenishment systems: how do you test for development times? I don't see the point with a Jobo. If I were using tanks with large volumes then I might use replenishment for economical and practical reasons, but one shot developers are the way to go with a Jobo.l

This does not make sense. There is no need to test replenished XTOL.

Steve

[jeroldharter]

Apparently I don't know what I am talking about. I'll yield to those who do. Nevertheless, despite difficult to control variables in any method, I think 1-shot would be more consistent for the typical darkroom.