Does anyone have any knowledge of Process B-41? (This is not a mis-print for C-41)
In 1949, Eastman Kodak put on the market a sheet film called "Ektacolor Type B". It was a tungsten colour negative film of 8 asa, intended for user processing in the "Kodak Ektacolor processing Kit". The Process was known collectively as Process B-41.
The processing kit is mentioned in the EK data book for Kodachrome films of 1952. It's also mentioned in the data sheet for Ektacolor type B film as of March 1957.
In the 2nd edition of the "Kodak Color Films" booklet, published by EK in 1956, on page 27, there is a note on negative processing faults, relating to processes C-22 and B-41. One of these faults is an overall reddish fog. Item 4 states that the cause of this fault is by "ommiting the FIRST USE of the Hardener and Fixer............"
Move forward to 1959 when the 3rd edition of "Kodak color films" was published, on page 20 the note on negative proccessing faults appears again. This time Item 4 states "ommiting the Hardener and Fixer......."
By 1959 only the C-22 process was in use.
C-22 has only one Hardener and one Fixer.I used the process for nigh on eight years starting in the pre C-41 days.
Was the Hardener and Fixer used twice in B-41? Why does it say "First Use"? I would like to know the differences between the B-41 process and the C-22 process, as regard to solutions, process times, temperatures, etc.
By 1959 C-22 was standard for Kodak colour negative films - Ektacolor Type B and B-41 dissapeared in 1958 to be replaced by Ektacolor Type L, a much faster film at 25 asa at one fifth second.
I put this post out originally in July this year but received no replies. I did'nt expect to get inundated with replies but there must be someone out there who has used B-41 many years ago. It was a user process, not like K-12 or K-14. (Kodachrome) Can anyone help? MT
I have those books starting with the first edition in 1950 and ending with an edition published in about 2002. I have data sheets and have been processing color negative and reversal since the processing kits went on sale and I never heard of B41.
There was C22 and E1, followed by E2 etc.. Until E6 and C41.
Before that were a number of internal processes used by Kodak that were never released to the public. One was used for the lenticular film called Kodacolor, which gave a positive image, not a negative, and the other was for unmasked color negative films which gave a silver mask not an orange mask. A third was for the first masked negative films, which also was internal and AFAIK used CD1 or CD2 as developer and a quinone / sulfuric acid bleach. I have mentioned this before on APUG. It was also used for color paper.
At the time of the consent decree, the C22 process was first released outside of Kodak.
In the 1950 book, there was no mention of any process for negative films or color papers whatsoever. It was not until the consent decree that these were published. It vaguely hints that the amateur could process reversal films, but that is all.
No outside facility processed Kodak products until the consent decree.
This may be different in England or other European sites. Or, you may have an internal handbook.
I might add that most Kodak products of the time used sulfite clearing baths sometimes before and after bleaching (especially if the bleach was dichromate), an alkaline formalin hardener, or an acidic chrome alum hardener. I would have to look up the details as to which went with which process, reversal or negative (C22).
To Photo Engineer
Thanks for your reply.
I am surprised that you hav'nt heard of Process B41. Perhaps we have different Kodak books!
A reference is made to it on the data sheet for "Ektacolor Print Film" (data sheet of March 1957) Processing ..."it can be processed in Kodak Ektacolor processing chemicals, Process B-41...". Apparently, Ektacolor Print Film could be processed in C-22 or B-41 (page 27, Kodak color films, 2nd edition 1956),
Ektacolor Print Film was marketed as from 1950.
From my own point of view I think that B41 was an earlier version of C22, very similar, most likely the same operating temperature, E1,as of 1949, and P122 ,as of start date, were used at 75F ,so I can't see B-41 being different.Maybe there was an extra hardening bath at the end of processing, like a stabilizer. C-22 was probably an improved version of B-41.
Kodacolor negative film and prints did not reach the UK until 1956-57.Kodacolor was described as "NEW" by the British Journal of Photography Almanac of 1958, despite the fact that Kodacolor had been around in the USA for sixteen years! At that time in the UK colour negatives and prints were Agfa (mainly) ,Gevacolor, Pakolor,and (very limited) ICIcolor. Synthacolor and Raycolor were amateur printing processes of that time.
In the early sixties, Pakolor even marketed a Reversal Print process for amateur photographers, like Kodak Ektachrome paper.
E1,E2 and E3 all used a Clearing Bath before the Bleach. In fact in the E1 and early E2 processes the clearing bath was a Fixer, to be used twice, once before and once after the Bleach - 5 mins, and then 3 mins, at 75F. Bleach was 8 mins.washes in between. By 1959 the formula of the Clearing bath had changed to that of a stop bath, and then the E2 process, and later E3 used only one fixer.Some experimentors in the UK used a glacial acetic acid + sodium acetate clearing bath for E2. I should imagine this was close to the Kodak formula.E3 replaced E1 around 1958-59.
I shall continue to try to find out more on B41. MT
I have commented on US information only. In the US, information back to 1950 only describes a C22 process for color negative.
Clearing baths were sulfite baths intended to scavenge color developer before going into a strong oxidizing bleach bath. That is about all I can add.
Michael, there is a brief reference to this in George Eaton's introductory style book, "Photographic Chemistry" (1965 w/original copyright = 1957). It's in chapter 13, "Practical Color Processes".
Eaton lists B-41 in two tables: one is photomaterial vs process, the other lists basic steps in several processes. These basic steps do NOT say anything about time, temp, formulations, etc.
Here's excerpts with the basic info:
From Table IV, Material vs Process
Kodak Ektacolor Film, Type B B-41
Kodak Ektacolor Film, Type S C-22
Kodacolor Film C-22
Kodak Ektacolor Print Film C-22 or B-41
From Table V, here are the steps; note that the step descriptions for C-22 and B-41 are identical except for 9:
1. Developer, 2. Stop Bath, 3. Hardener, 4. Wash, 5. Bleach, 6. Wash, 7. Fixer, 8. Wash, [for step 9 see next part] 10. Dry.
In the case of C-22, step 9 is "Remove water droplets by wiping or with Kodak Photo-Flo Solution. In the case of B-41, step 9 is "Bathe in Kodak Photo-Flo Solution plus 3/4 oz. Kodak Formaldehyde per gal."
My best guess whould be that, aside from step 9, the two processes are fundamentally very similar (possibly even identical) on the basis of either being ok for "Ektacolor Print Film". The oddball seems to be that Type B film needs B-41 process; one could make many guesses as to why, but it seems doubtful that a conclusive answer is going to surface here.
I would suggest you just take the info as is and don't try to justify why it is so. If you are tempted to guess, here is a run of speculation to help dissuade you. Maybe the 'B' film had a new style ballast on the coupler and needed a bit of a certain solvent in the developer. Why then is that developer ok for "Ektacolor Print Film", but not for the "Type S" or Kodacolor? Well, maybe the latter films have issues with emulsion swelling, etc, in certain mix water conditions, but the former film has been toughened agains this. well, why not toughen the other film, etc, etc? Or maybe the "B" film releases a certain byproduct which affects some films but not others. So you can see what a slippery slope this speculating can lead even the layman to. Someone who knows the chemistry, like PE, could speculate on and on, going much much deeper, I'm sure.
BTW, I think it is perfectly ok for PE to not be aware of (or remember) a possibly obscure process of 40 or 50 years ago. To me, someone who understands things and can explain (at some level) is much more valuable than one who merely has access to trivia.
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Thanks Mr. Bill;
I have George Eaton's 1957 copy of the book and it does indeed include the B41 process. I totally overlooked it.
Interestingly enough, the B41 and C22 processes seem to be inverted as the formalin with photo flo went with C22 not the other way around. This is quite odd, as I even have some C22 stabilzer here along with the rest of the kit. The Ektacolor Type B and Ektacolor S were similar films differing mainly in the relative speeds of the 3 light sensitive layers, so the processes must have been very close if not identical except for that one step.
Thanks for the detective work. I would have missed that entirely. I don't pull Eaton's work out often.
Thank you Mr. Bill for solving the mystery of B41.I did'nt think there would be much difference in the processes.
Yes, it is perfectly OK for PE to not be aware of a 50 year old process. I was just a little surprised that the Kodak books I got the information from did'nt match the Kodak books owned by PE. They are all genuine Kodak film books, printed and published in the USA.
I am not a photochemist, but I am just interested in why things happen with regards to colour processing and printing.
Thanks again for the info on B41.
Incidently, when I was at Art college, I used to put Ektacolor Print Film through E3 Stabilizer instead of the C22 Photo Flo rinse! MT
At one time, the C22, C41, E1, E2, E3, E4 and E6 stabilizers were virtually identical if not identical. The only difference was in the solid kits which used paraformaldehyde instead of formalin solution.
Sorry I couldn't find that answer, but Mr. Bill pointed me to a book that had it. I think that there were different editions sold in England and the US. That is the only explanation.