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John King
12th November 2015, 10:48 PM
I have just seen on the AG website that Tetenal are discontinuing the 1ltr C41 kit! But the good news seems to be Tetenal are replacing this with a 2.5 ltr Kit.

I am currently using a Fuji 5 litre kit, however I fear that I may not be able to use it all before the developer 'A' solution goes off, it has started to take on a distinct yellow tone where before it was clear. A 2.5 ltre kit would be just the ticket and probably proportionately cheaper than 2 x 1 lite kits..

Mike O'Pray
13th November 2015, 03:06 PM
The developer is as I understand it, the weak point of any C41 kit. One of the attractions of the Digibase kit was the ability to buy fresh small bottles of developer separately.

Few if any other kits seem to sell developer separately. Does AG still sell the Digibase kits, indeed is there still a Digibase kit?

If anyone is only an occasional user of C41 then the 2.5 ltr kit may be too much.

I used to be a fan of the small powder kits produced for Silverprint by Michael Maunder. Alas the kits are no more. OK once mixed it had a limited life and would have been expensive for just one film but in small batches was ideal. Each powder kit in an unopened condition had a very long, if not almost indefinite life

So, anyone have any knowledge of the current state of Digibase C41 kits?

Thanks

Mike

John King
14th November 2015, 12:21 AM
AG don't sell the Digibase kits but they are apparently available from Firstcall in Taunton. Matt from AG told me when I rang up for advice that they had discontinued them, something to do with unreliabilty of the mixes.

I initially thought Digibase were good, but the films although gave a correct density always seemed to lack colour saturation. I never had the problem with Tetenal or with my FUJI kit. The 5 litre Fuji kit seems to be too big for the quantity of fims I use. Additionally measuring out the small quantities of FUJI, to make enough for one film to be consistent really needs far more accurate measures than I have.

AndreaP
17th November 2015, 12:31 PM
I have used Tetenal without any problems but the digibase i dont like at all - just didnt seem to work and that was on the first attempt will try it again as have just shot a test roll for the purpose but will go back to tetenal as definately better results

Tom Kershaw
20th November 2015, 05:24 PM
I'd keep going with / recommend the Fuji kit. It has separate bleach and fix solutions which is better technically, for why see the other place. I have used the Kodak C-41 products in the past but you need to be processing a lot of film to make it worthwhile. Also figuring out what items to order from Kodak can be a research project in itself.

Tom

Mike O'Pray
20th November 2015, 07:21 PM
Andrea, there was a 30+ page thread on this kit a few years ago on APUG and I went through it as carefully as I could in an attempt sort out the "wheat from the chaff" so to speak.

What I came up with as a process was as follows:
1. Pre-wash 2 x 30secs - water at same temp or a degree higher than developer temp
2.Developer(100F) 3 mins 15 secs
3. Stop 30 secs continuous but slow hand inversion. You could use the Jobo processor but the rotary action tends to blow off the red rubber cap and lose the stop
4.Bleach 6 mins 30 secs
5. Wash 4 x 30 secs
6.Fix 6 mins 30 secs
7.Wash 4x 30 secs + 2 x1min
8.Stabiliser 1 min

What may be significant in the above list is the bleach and fix times especially the bleach. Most kits especially my previous kits had used blix and none required anything like a total of 13 mins for bleach and fix

It may be that shorter bleach times lead to retained silver which can give rise to "de-saturated" colours as has been mentioned.

It does make the above process quite long by most standards and may be over the top but if you haven't been using these times it might be worth a try.

Having said all of the above I now need to add that I had paid particular attention to the thread mentioned because I had bought a kit from Matt at AG but had not and still have not used it

So what I give above is not based on practical experience but simply on gathering information from those whose opinions on APUG I felt I could respect.

One day I will try the Digibase kit so if you decide to give the above process a go I hope it will be helpful. It will certainly be helpful to me to know how it went

Thanks

Mike

KevinAllan
21st November 2015, 10:31 AM
I have used both the Digibase and Fuji kits; if anyone wants to see some samples, these are with Digibase chemicals:

https://www.flickr.com/search/?user_id=33186310%40N03&sort=date-taken-desc&text=DIGIBASE&view_all=1

and these more recent images are with Fuji chemicals:

https://www.flickr.com/search/?user_id=33186310%40N03&sort=date-taken-desc&view_all=1&text=fuji%20hunt

Mike O'Pray
21st November 2015, 01:23 PM
Thanks Kevin. I suppose the real test is the same picture in the same light conditions but developed in the two developers but at a quick glance I can't see any real difference.

What do others think?

Mike

John King
21st November 2015, 06:54 PM
The lack of obvious difference could be down to the reproduction on the various screens of the computers used to view them.

The samples I put up last week appear to be quite unsaturated, even dull when compared alongside the originals.

JOReynolds
22nd November 2015, 02:31 PM
What I came up with as a process was as follows:
1. Pre-wash 2 x 30secs - water at same temp or a degree higher than developer temp
2.Developer(100F) 3 mins 15 secs
3. Stop 30 secs continuous but slow hand inversion. You could use the Jobo processor but the rotary action tends to blow off the red rubber cap and lose the stop
4.Bleach 6 mins 30 secs
5. Wash 4 x 30 secs
6.Fix 6 mins 30 secs
7.Wash 4x 30 secs + 2 x1min
8.Stabiliser 1 min


What on earth is the stop bath for? You are specifying a separate bleach and fix, which is to be applauded.
The original C-41 process specification calls for the bleach to follow immediately after the developer.
The detailed Eastman Kodak C-41 process specification makes it clear that cyan dye coupling continues during the PDTA bleach step, which is designed to withstand significant developer carryover. The implication is that coupling may not complete if the pH is reduced by stop bath carryover.
Whereas combined blix has a strong affinity for oxygen and is degraded by oxidisation, C-41 bleach must be kept well-aerated.
Why specify a wash before the fix?