Do you add developing time when you reuse the chemicals?
I am a Jobo ATL 1000 user. Recently i tried to reuse my chemicals and the result was great. I pushed one stop in case the chemicals became weaker after i used them.
Did i have to do that or it is ok to reuse the chemicals 2-3 times with no pushing?
Looking forward to hear your opinion!
Depends, what films and what chemicals (I'll presume you're talking about colour)?
Also, how many of what films are you doing at once?
I did my first 4 sheets of 4x5" Velvia in a 1L Tetenal E6 3-bath kit a few weeks ago, in my Jobo CPE2+Lift with 2509n. I measured the raw chems precisely and diluted accordingly to 350ml, and gave it 7:30 in the FD, they came out perfect.
The next weekend, I re-used the same chemicals for another 6x sheets of 4x5" Velvia, and gave it 8 minutes, again, perfect.
I've kept those chemicals, but won't reuse them again for anything important. I've got another 6 sheets of RVP to do, but I'll measure out a fresh 350ml and try to reuse them within a week or two of mixing them. (oh damn, I'll have to go out and take more photos )
When I've done this mix/reuse once more for the last 300ml of the kit, I'll mix all 3 lots of used chems together and play around with some old expired crapfilm (ektachrome from 1982 anyone?) and/or cross-processing...
Tetenal themselves recommend 12 rolls / sheets of 8x10 (48 sheets of 4x5) per 1L kit, "if you process 2 rolls at once" (ie 8 sheets of 4x5). Nothing wrong with doing less at once, or putting more films through, depends how picky you are about the results (FWIW, I can't see the difference in my first and second batches, YMMV)
I've also got some expired NPS and fresh Portra160 4x5s waiting to be processed with some Powder (forgot which brand) that's waiting to be mixed, but for that I'll just mix the whole 1L and keep pouring it back into the stock once I'm done. I'll be watching this thread to see others' reccomendations on extra times for that, I've never done C41 before.
An awful lot of electrons were terribly inconvenienced in the making of this post.
Hi! thanks a lot for your reply!
What an idiot of me.. forgot to say that my question is about C-41 chemicals. I use Digitise. The films that i processed recently are Portra 400 and Agfa Ultra 100.
Originally Posted by Dr Croubie
First time i processed 2 rolls with 270ml of each solution. The second time again 2 rolls and as the machine drains about 220-240ml of each solution, i added the rest mixing new chemicals.
Originally Posted by Dr Croubie
How did you know how much time you had to add the second time? I've read somewhere that people add 10% of developing time each time. Thats why i pushed it one stop (3:45 instead of 3:15). But this math with 10% each time made me confused. Maybe i misread that? What if i want to reuse the chemicals the third time? Pushing +3 stops? Sounds weird....
What should i do now: Push 2 stops or try the same 3:45 min )+1 stop)?
The Digitise manual says that the capacity of 270ml solution is 3-6 rolls. That's why i assume, that i still can use my solution one more time.
The manual will also say what time to use for 2nd 3rd film and how long the used developer lasts...
Originally Posted by ala
Processing longer for partially used developer is not pushing.
Read the manual more carefully.
Thanks for the reply.
Sorry, what manual do you mean?
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Most C-41 is a replenishing system. You pour out some old and add the fresh replenisher. So you can keep the chemicals pretty much forever.
Most people use the developer as on-shot, or run it twice until the manufacturer's capacity is reached. You can possibly use it more than that and add some time, but it is not recommended.
Developer is cheap.
You normally buy C41 chemicals as a kit with an instruction manual for mixing and use.
Some are abstract.
Thanks for the information. What you say about using bleacher and fixer adding some new solution every time is interesting... If i use 270ml, the machine pours out about 240. So additional 30ml of a new solution is enough to keep it alive? Don't bleacher and fixer "loose their power" like that?
Then i am a little confused with the capacity thing. This is a manual for my chemicals http://www.macodirect.de/download/C4...tionManual.pdf
Let's say, i use 270ml of a Bleacher. It says "capacity - 5-8 films". I thought that after i process 8 films with this solution, it can't be used anymore. Do i understand correctly now, that 5-8 films mean "during one process you can load up to 8 films, but you can reuse it forever"?
Thanks in advance!
Well, you'll have to read the instruction of your chemicals.
Only replenish system can be replenished. The replenishers (developer, fixer and bleach) are in general stronger than the working solutions. If the replenishing rate is 20 ml/roll, then that is how much you'll need to replace. Say, you use 300ml to process one roll of 135/36. After you save the used chemical (not contaminated), you pour 20ml new replenisher to the container, then top off with the used chemical to make it to 300ml. Pour out the remaining used chemical.
In theory, you can keep replenishing the chemicals and do not pour away them. But this system only works well if you use the chemicals on a regular basis, say, weekly, but not monthly. All C-41 solutions can be replenished.
But some chemical systems are not replenishing system. They are in general called one-shot, even though you can use it twice or 3 times.
Say, I use the regular T-max developer for B&W developing. It is a non-replenishing system. I believe for 1 liter working solution, you can process up to 4 rolls of 135/36. The next 4 rolls, you add 30 seconds to the developing time. Then add 1 minute to the next 4 rolls. I think the total capacity is either 12 or 16 rolls... Then it is time to throw it away. But most of the people probably just use it once. So if the tank capacity is 250ml, then the capacity is 4 rolls per liter.
Thanks a lot for all the information. After i saw your post i reread the manual for Rollei Digibase c-41 and started looking on different forums if it is a replenish system.
It is said in the manual, that the used chemicals should be stored properly before the next use. It makes me think that these chemicals are made to be reused. But there is no information about any replenishing rate or additional time for the development for the used chemicals.
I am going to write to macodirect.de support asking about that.
Meanwhile if anyone has any ideas, please share. Thanks in advance!