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  1. #1

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    Speedibrews Celer -41 Kit for Colour Neg Processing

    Anyone had any experience of using this kit? It is sold by Silverprint and seems to be about the only economical kit for low volume users as it is in powder form.

    Silverprint's website recommends a maximum of 4x35mm films from the 600ml kit but the Speedibrews overview section carried by Silverprint says up to 8 films.

    It's not clear whether each kit is 300ml of developer and 300ml of blix hence the reference to a 600ml kit or 600ml of developer and blix. It is a room temperature kit but doesn't specify what room temperature is. No doubt this is covered in the instructions.

    I must admit I have never come across a room temperature C-41 kit before and I am left a little uneasy about whether there might be any drawbacks to such things as longevity of negs.

    If it is only 4 films then it's not particularly cheap at about £2.20 per film but at least you can be sure of its keeping qualities in that a kit stays in powder form until needed.

    Can the powder be split in half to process say 2 films to extend its life? If not then how long might it last in liquid form?

    I have e-mailed Michael Maunder himself as he invites one to do so on the Speedibrews website but I may wait a while for an answer.

    Equally a call to Silverprint with these questions is in order but there's nothing like getting user experiences, should of course anyone out there use or have in the past used this kit.

    Thanks.

    pentaxuser

  2. #2
    Dave Miller's Avatar
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    Whilst I know Michael from my days in the Woking P.S., and have used most of his products, I have not used this one. If he says it will do a job I think you can rely on that. You must not try and split the dry packs, the chemicals are not evenly distributed in the bags, so you will get uneven results.
    Regards Dave.

    An English Eye


  3. #3

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    Quote Originally Posted by Dave Miller View Post
    Whilst I know Michael from my days in the Woking P.S., and have used most of his products, I have not used this one. If he says it will do a job I think you can rely on that. You must not try and split the dry packs, the chemicals are not evenly distributed in the bags, so you will get uneven results.
    Thanks Dave. Unfortunately that's what I thought. It seems a little strange that Silverprint should "downrate" Michael's products by 50%. It could of course be just an error in typing or interpretation. Silverprint who obviously endorse Speedibrews products would have no reason to contradict him. Since the issue of Silverprint's rudeness I have looked very carefully at its website and whatever else might be said about its approach to the customer I am absolutely convinced of Silverprint's honestly and intergrity in its approach to giving customers an honest deal.

    As you know Michael Maunder can you say what the chances are of me getting a reply from him?

    Thanks

    pentaxuser

  4. #4
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    All C41 films are very thick by comparison with B&W films. They also do not swell easily due to being designed for high temperature processing and scratch resistance. The incorporated DIR couplers and the iodide effects are designed to work at high temperatures.

    Therefore, all attempts to process at room temperature usually run into a diffusion problem causing severe mismatches in color reproduction as a function of layer order. The chemistry is designed for 100F (38 C) processing and does not work well at lower temperatures.

    Generally, when the bottom layer is properly developed, the top layer is overdeveloped. If you add ingredients to repress the top layer, you mess with the color reproduction, and so it goes, on and on in a vicious circle trying to fix one problem after another.

    If you go the other way, and add ingredients to push the bottom layer, then the top layer is still overdone and you again fall into the same loop. It is like trying to squeeze a baloon full of water without breaking it, but with a handfull of needles.

    BTDT.

    Good luck.

    PE

  5. #5

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    Quote Originally Posted by pentaxuser View Post
    Anyone had any experience of using this kit? It is sold by Silverprint and seems to be about the only economical kit for low volume users as it is in powder form.
    I've not used it, but I do have some comments. FWIW, most powdered C-41 kits I've seen are sold as "press kits," presumably because press photographers find it easier to carry around powders than liquids.

    Silverprint's website recommends a maximum of 4x35mm films from the 600ml kit but the Speedibrews overview section carried by Silverprint says up to 8 films.
    Assuming 300ml of working solution per roll, getting four rolls from a 600ml kit would mean two uses per 300ml, and eight rolls would mean four uses. Re-using C-41 chemistry is possible, but the quality may drop a bit with each re-use. Personally, I've never tried more than two uses per ~300ml.

    It's not clear whether each kit is 300ml of developer and 300ml of blix hence the reference to a 600ml kit or 600ml of developer and blix.
    In other kits I've seen, the volume specified has always been per item (a "500ml kit" is 500ml of developer, 500ml of blix, etc.). I can't promise the same is true of the one to which you refer, but I suspect it is. If not, that'd mean twice as many uses per 300ml.

    It is a room temperature kit but doesn't specify what room temperature is. No doubt this is covered in the instructions.
    Few or no C-41-type mixes work well at room temperature. I've seen some that claim to work at a variety of temperatures, but the instructions usually say they work better at 100F. The only exception I know of is NCF-41, which is an unusual mix-it-yourself divided developer. Unfortunately, my experience with it is that it's a rather hit-or-miss formula -- sometimes it produces very nice negatives, but almost as often it produces underdeveloped negatives. The bottom line: If the instructions give you options, use the 100F developing procedure.

    I must admit I have never come across a room temperature C-41 kit before and I am left a little uneasy about whether there might be any drawbacks to such things as longevity of negs.
    PE knows a lot more about this than I do, but my hunch is that a room-temperature process would be more likely to result in color shifts, thin negatives, or other problems that are obvious from the start than to produce good-looking negatives that fade faster than they should. That said, older C-41 films require a stabilizer as a final step, and some C-41 kits omit this stabilizer. Newer films can use a "final rinse" instead of a formaldehyde-containing stabilizer. If you buy a kit without a stabilizer, you should probably buy some, or perhaps a final rinse product if you're using newer films that you know don't need the old-style stabilizer.

    Can the powder be split in half to process say 2 films to extend its life? If not then how long might it last in liquid form?
    Generally speaking, this isn't recommended because you're likely to get uneven separation of components. If you absolutely must do it, be sure the powder contents are well-mixed before you proceed. You could also save up your film until you've got enough rolls to use up the entire kit at once.

  6. #6

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    Thanks all for the answers. Unfortunately no-one replying has used this kit which is a pity as I have two supplementary questions that now arise from having received the kit.

    In case there are others in the U.K. considering Celer 41 let me now expand on what the kit instructions say before asking my question. Can I also say that I'd welcome those with knowledge of C41 such as PE and others who haven't used this kit to also reply as I suspect that good answers to my question may not depend on having actually used the kit.

    Overall the kit instructions are well written and easy to follow.The kit seems very versatile. So what do they say?

    Well, it is in fact the kit is designed for use at normal C41 temperature of 38 degrees C but can be used as low as 20 degrees C.

    It makes 600ml of developer and blix which as others suggested in this thread was likely to be the case.

    It gives instructions for push processing and covers film capacities. In a tank with 300ml it will process 3 films before throwing the dev away so 600ml will process 6 films. Using all 600ml each time then 8 films can be developed but if the films aren't done one after the other then the part used dev has a storage of only 2-3 weeks which is short. I'd be unlikely to shoot say 7 more film in a 2-3 week period if I had only one to develop at the start.The alternative is to split the unused dev into smaller bottles filled to the top and use as two or more portions.

    In the case of my JOBO tank this could be usefully broken down into 4 x 150ml portions and assuming that each 150ml would process 2 films, this would give a maximum processing capacity of 8 films.

    The kit says that up to 8 films can be processed in 600ml so I would assume that instead of processing 8 films one at a time in the same used 600ml of developer that 2 films processed in 150ml and then dumped would not be a greater strain on the developer. This is one film in unused dev and one in the same used once dev.

    Is my logic sound here as I am now asking 300ml to do 4 films instead of 3 films as per the instructions, albeit 2 out of the 4 films get fresh dev. Whereas if I use 300 ml each time then only one film gets fresh dev but presumably the other two are processed in less exhausted dev than the 2nd and 4th film using 150ml in two portions?

    It must all depend on how the chemistry works and that's where I need answers. If each 150ml has to be one shot then this gives me 4 films only whereas 300ml twice will give me 6 films and 600ml once will give me 8.

    The kit's instructions go on to cover development of B&W chromogenics such as Ilford's XP2 Super and even normal B&W without of course the use of the blix! In fact it claims that ordinary B&W films rated at their box speed give very fine grain in this kit and mentions Tech Pan 2415 as a particularly good combo. It suggests that 10 mins is an average time but it is a question of you finding the optimum time.

    Anyway now to the other part of the instructions that give me some concern.

    Clearly the designer of Celer 41 had in mind customers who didn't possess a rotary processor. Under these circumstances the instructions say a time of 3mins 15 secs for dev using 15 sec continuous agitation initially then 5 per 30 which I assume to mean 5 agitations per 30 secs which equates to at least 5 secs or a little more per 30 secs.

    So for non rotary processing hand agitation wouldn't be continuous but conceivably might be more vigorous.

    The instructions go on to say:Rotary Systems are easier to us and normally need 25-30% less development time.

    Taken at face value this means that in a rotary processor, which normally calls for the same 3 mins 15 sec in other C41 makers' instructions with continuous rotation, now only needs between 2 mins 17 secs and 2mins 27 secs in Celer 41 with continuous rotation?

    This seems a very short dev time which I have never come across before. I am worried that the film may be greatly underdeveloped. On the other hand if I stick to a time on or close to 3 mins 15 secs then as this is some 48 secs longer than recommended the film could be way over developed.

    I managed to overdevelop a film once in, I think, Paterson developer for about an extra 30 secs and this gave difficulties in printing but it was still possible. However this is 48 secs more not 30 secs

    So short of getting an answer from the kit's designer which I haven't managed to get what would be your advice as to how I proceed in terms of development time?

    I suppose the safe answer is to shoot a 12 frame film of unimportant shots then use the recommended time of 2 mins 27 secs and see what happens but that certainly will hold things up.

    On the lesser issue of film capacity would you: A. Play absolutely safe and use 150ml as a one shot and do 4 films
    B. Use 150ml as a two shot and try 8 films with 4 portions
    C. Use 300 ml as a two shot and do 6 films with two portions.

    This last question is somewhat academic as I haven't got 8 films to do but should I ever have, it would be nice to have opinions as to whether this is 2 films too far.

    Thanks for taking the time to read this and double thanks to those who have the time to reply.

    pentaxuser

  7. #7
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    Here is an answer from a guy who designed one generation of Kodacolor Gold.

    That time is too short for proper 'normal development'. It is, as I stated before, a diffusion problem. For a thin B&W film, you could indeed do what they say, but for a thick color film the result would probably be severe crossover due to mismatched curve shape. There is no easy answer to get to room temp development or shorter development times.

    It took us years of development to get the match between film and developer to work. Then, each new generation of film had to be designed to fit that C41 process.

    BTW, neither Fuji nor Agfa have ever had to design a film and process from scratch. All processes existing today for color products are based on Kodak research. I doubt that this company could do the level of R&D necessary to make this work properly. It may work with one film, but not all.

    The bottom line is this. If you use the kit do the following:

    1. Use a Jobo or similar drum at 100 F.

    2. Presoak the film to get to 100F.

    3. Throw away the used developer.

    4. Use 3' 15" at 100F.

    That should work. At the worst, you will give the film a slight overdevelopment. This is much better than thin negatives.

    PE

  8. #8

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    Thanks PE. To be fair to the Celer 41 designer I believe that his feelings indicate that if the user wants safest processing then he should do all you have said except for the rotary processing time, having read the instructions several times.

    The only way I suspect I am going to get to the bottom of his reasoning for the rotary processing time reduction is if he favours me with a reply.

    He meets with the owner of Silverprint as he still does the kits for Silverprint instead of selling them himself. He is now semi-retired. So maybe an answer will be forthcoming via that avenue.

    If he decides to stop producing then the product will vanish unless Silverprint can persuade him to sell the know-how and presumably teach someone else to make it.That's likely to depend on the demand for it.

    Judging by the number of APUGers who use Celer 41( none so far it appears) then the demand may not justify any action by Silverprint should he totally retire.

    To keep the record stuck in the same groove " Times are worrying for low volume U.K. colour enthusiasts"

    pentaxuser

  9. #9
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    I've only just picked up this thread again, so apologies for not replying earlier. I haven't seen Michael Maunder for several years. I thought that he had retired to the Channel Islands to indulge in his passion for astronomy, and had given up the production of chemical kits. I should address your question to Martin at Silverprint in the first instance, if you haven't already done so, and ask him to relay your question.



    Quote Originally Posted by pentaxuser View Post
    Thanks Dave. Unfortunately that's what I thought. It seems a little strange that Silverprint should "downrate" Michael's products by 50%. It could of course be just an error in typing or interpretation. Silverprint who obviously endorse Speedibrews products would have no reason to contradict him. Since the issue of Silverprint's rudeness I have looked very carefully at its website and whatever else might be said about its approach to the customer I am absolutely convinced of Silverprint's honestly and intergrity in its approach to giving customers an honest deal.

    As you know Michael Maunder can you say what the chances are of me getting a reply from him?

    Thanks

    pentaxuser
    Regards Dave.

    An English Eye


  10. #10

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    Thanks Dave I suspect your second reply and my latest to PE may have crossed in the e-mail as they say. My conversation with Martin at Silverprint elicited the facts about Michael Maunder as in my reply to PE. It seems he does the business for Silverprint as and when they require fresh stocks but he's not getting any younger. I wasn't sure if he makes up the packs in the Channel Islands and sends them to Silverprint or travels across and does it at Silverprint.

    As far as the future of Speedibrews is concerned it's a bit like Ilford being only Simon Galley and us relying on him to produce all the goods when he is already way past retirement age.

    Can you imagine APUG's reaction? Well this is a good analogy. It seems to me that Silverprint might persuade Michael to sell the Speedibrews secrets and train someone to carry on but of course it has to make good business sense or at very least be a break even which Martin uses to boost Silverprint's reputation for an allround service with knock on benefits.

    Michael's address is certainly the Channel Islands and I think the e-mail address I got from the Speedibrews site must be OK otherwise the mail should have come back as undelivered.

    As you say the leverage to get an answer is probably best applied via Martin.

    Pentaxuser

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