C41 (fresh chemicals) resulting in dark film base

alienmeatsack

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Hi all. Can someone here give me some thoughts on these negatives?

I am using the Tetanol C41 kit, mixed freshly using distilled water as I always do. I've run one batch of 35mm film through it day before yesterday and the negatives were completely normal for the films I was using.

Today, I heat the solutions and go through my normal routine of 3.5-4 mins for the Developer, 6.5-7 mins for the Blix and the resulting film bases are both is dark. It's two different film that I work with regularly, one is sometimes a little dark base wise but never like this.

I usually only see this when the chemicals are old and have been used a lot, or the film is expired heavily or certain brands of film that tend to be darker then others.

The first two rolls from this new set of chemicals were done as I always do and resulted in lovely sharp and contrasty images with about half as dark film base as these.

I tried a second batch with another roll of similar film and made sure my chemicals were up to temperature and I did the steps for as long as I was supposed to and I got the same dark film base as the others, maybe even darker.

Is it possible it's contamination of the Developer? Or a problem with the chemicals? I've done 100+ rolls through these kits before this and never had this dark of a base before on anything. Especially not film I had used many times before without problems.

Suggestions thoughts feedback etc?

(Two screen shots are attached to give you a semi-decent idea of what I'm talking about. I used my iPod to backlight the film. You can see the numbers and coding on the film just fine in the shots.)

photo_1-20130905-215933.jpg


photo_2-20130905-220007.jpg


I don't have another new color kit handy to mix another up fresh but can order one if I need to. I just wonder what the problem is since this is a fresh kit and has produced fine results previously. I had temperatures the same etc.
 
FYI... I've been scanning one of the 2 rolls in question over the last 20 minutes. They appear as jet black images on the scanner in preview mode because the base is so dark.

I just have to make a selection and move it around to get a preview that is adjusted and make my selection to scan from that.

The only time I've seen this previously was redscale and a few films with a darker base. So not sure what happened here. I did notice that both rolls of 35mm were expired Konica, but the 3rd roll was expired Portra 160NC in 120 format and I've never had it do that dark base thing before. So still a mystery.
 
Looks like base fog to me, just like you get with out of date films. Should be able to get something in the scan software...
 
I think I see Konica on your photos of the negatives. I believe Konica color film was last available fresh around 2009, so fog associated with outdated film, as suggested above, may very well be the problem.
 
I think I see Konica on your photos of the negatives. I believe Konica color film was last available fresh around 2009

Their film section was globally shut down early in 2006, but they had been pulling out of film ever since the Minolta merger in 2003. Given that expiration dates tend to be two or three years ahead from packaging on consumer CN film, some time in 2009 might be the very last expiration date on any of their films - the majority of Konica film still floating around will be even older than that, so age related fogging is likely indeed.
 
Note that I also mentioned in my post that I also developed some -new- color film in it just after that was not foggy or expired or old and it's base was also extremely dark.

And I've never had Konica (mines from around 2005-2006 I think) this dark before. Which is why I wonder if it's a problem with the chemicals.

I'm going to order a new kit to be safe, get some fresh new distilled water to have on hand. And do one more run through it with film I know comes out normally. It it does the same I will get rid of this batch. A pity as it's fresh and should have given me 20-40 rolls of development.
 
Well, since it's a fresh kit, I'd hope the bleach was not exhausted. It's literally had 5 rolls run through it.

I am going to do a test roll this weekend with it and try running the Blix time up by 30 or so seconds. I've always done 6.5 minutes for the first 10 sessions (be they two 35mm rolls each or one 120 roll), then added 30 seconds to it to make the time 7 minutes for the next 10 sessions. And then added 20-30 more seconds to it for the next 10+ sessions and never had issues like this.

I still think maybe it's a bad kit or maybe some cross contamination. Who knows. I just don't have another on hand to mix up at the moment to make sure. I have considered taking one of the rolls of Konica to Walgreens to see how their negs turn out for comparison.
 
Update to this problem...

I've developed an assortment of new and expired films in this batch of C-41 developer since this post, including some E-6 film. I am still getting the darker then usual base on everything. The new C-41 films aren't as bad but are still way darker then anything I've developed in the past. I did a visual comparison to some older rolls of expired and new films and there is definalte y a difference.

It has to be a bad batch of chemicals or cross contamination or similar. That is the only explanation. I've watched all of my supplies thoroughly, I've cleaned the containers between batches of chemicals, I use the right water and mix everything right, maintain temps etc.

So it has to be the chemicals.

I'll order a new batch and remix them and try again I guess. I don't know what else to do. Especially considering I've tried quite a few different films of different ages and developing types, all that worked ok previously.

I shouldn't complain too much... I've had great success in color development since I started doing it myself. So this really is the first time it has been "off" and I've put lots of film through the stuff during all these developing sessions.

The one thing I've not tried yet is to develop one of the rolls in question in BW chemicals to see how it comes out just to verify that the base can be clearer. I jsut hate wasting good expired and rare films like this when the results end up very difficult to scan.
 
I have similar problems with c41 kit. It is getting so dark, my scanner can't get it through.
Have no idea why, my first DIY color film kit.
 
Have you tried re-oxidizing the blix?

the Bleach in the blix can be replenished with oxidation. Just shake up your blix 1 min before you go to use it. This may help.

Also are you maintaining blix temp throughout? I usually have a tub of hot water I use to warm my chem. While Im blixing I leave my tank sitting in the warm tub to help keep the temp up throughout the time. I find that it falls quickly without.

If you are blixing for 7:00 that should be more than enough. I would look at temp and oxidation as mentioned.

I have had this before when xproing a roll of very expired provia. I ended up reblixing but it didnt help much.

Also your tetenal kit should have the same paper that my unicolor kit came with. It has a troubleshooting section.

good luck.
 
ZF1 - I have not tried re-oxidizing the Blix. I did not know this was a thing. I will give that a shot!

Yes, I am maintaining temperature throughout. Well, I am not 100% accurate on it, but I've done a ton of color rolls in these kits over the last 6-9 months or so and this is the first time I've had issues. I heat them up a little beyond the normal temp so when I move them to the waiting spot (in water) they will be about right. I also keep the 2 bottles sitting in hot water, and if I am doing more then one set of rolls, I'll put them back into a super hot sink to warm them back up and check the temp to make sure its close to where it should be.

As far as re-Blixing, this is something I can do? Even though it's dried and been Stabilized etc?

I just did another roll of color reversal (expired) tonight as well as a roll of color film (new) that both have very dark base again. I was going to try scanning them to see what I can get. I'd love to scan the Ektachrome stuff I did this weekend but it's so dark that I'm having one hell of a time getting anything off it. I never had much luck with it. But the Fuji Provia and Velvia always come out top notch for me when I XPro them in my C41 kit.

FWIW I don't (or haven't) done the B/W step like some folks step during the Xpro process nor have I "exposed" the negatives before the color process as some suggest if you B/W process them first. I just have run it through the C41 kit like normal many times and never had issues before.

I've considered sending a roll of to have a proper lab do an E-6 on it to see what they get too. I know these films work, but since they were loose, it's also possible that one or two of them are just aged poorly. But it doesn't account for the other films that have come out darker. Troubleshooting is fun to a point then it becomes annoying.
 
Just for giggles and since I had no idea what it would actually do, I decided to cut off a small part of one of the 120 rolls that was massively dark and run it through the Blix again.

First I shook the Blix well, then opened the lid, let it fresh O2, reshook, and repeated for about a minute.

Then, I put the piece of film into the Blix again (it's been developed, blix'd, stabilized and dried and exposed to light). I shook it heavily since there was O2 in there as well then did my normal agitation for about 5 minutes.

The original was dark blue on both sides with a very faint image if you shined a powerful light through it.

The re-Blix'd piece is now a little lighter blue on one side and tan/brown on the other. It doesn't appear to be any less dark though. I won't know until it drys and I can compare it. I figure it was a throw away anyway so why not play with it.

Maybe with the next roll I will just run the Blix process double the length instead and try to add O2 to the mix before hand.

Adventures in Blix.
 
Well, since it's a fresh kit, I'd hope the bleach was not exhausted. It's literally had 5 rolls run through it.

I am going to do a test roll this weekend with it and try running the Blix time up by 30 or so seconds. I've always done 6.5 minutes for the first 10 sessions (be they two 35mm rolls each or one 120 roll), then added 30 seconds to it to make the time 7 minutes for the next 10 sessions. And then added 20-30 more seconds to it for the next 10+ sessions and never had issues like this.

Adding 30 sec to bleach time is not going to help if you have exhausted bleach. Double/triple/quadruple the time. The bleach and fix (or blix) is run to completion, you basically can't over do it. I haven't used Tetenal C-41 kit in quite a while, but I seem to remember that even the Tetenal instructions recommended extending blix time up to 4 times (from 4min to 15min) as you use the kit.
 
Blix is rather unstable - even if you pay close attention to the expiration date and all storage/usage specifications, it may sometimes turn bad before being nominally depleted. Professional processes tend to use separate bleach and fix stages as these behave more predictably.
 
Based on the poor results I've had with this kit, I am going to replace it soon.

I am considering buying a new kit that is separate dev, bleach and fixer to have a little more control over the process. I've really enjoyed the simplicity of the C-41 3 stage kits but problems like this just remind me I need to keep growing.
 
I have been using the Unicolor kits with good results but I would be interested in finding the 4 stage chemicals with separate bleach and fixer. If you locate something that does not require the purchase of 25 gallons of chemicals at one time let me know.
 
I've not really looked for any outside of the Tetanol/Unicolor/Jobo kits. I was considering trying the Rollei 1L kit as a stop gap until I can find the separate chemicals. Theirs is still combined chemical stages however.

Seems like all of the "kits" are combined into 3 stages and all have a bleach/fixer stage. I wonder if there is a way to find a proper recipe for the bleach and fixer to make them yourself separately using alternative chemicals and get the same result?
 
Is there a chemical reaction required to make the Bleach work or the fixer work that is why these two are combined? Why can't one just leave the two dry mixes separate and mix them into their own water solutions and do them one at a time? has anyone tried this?
 
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