Can sodium carbonate solarize your film?

StoneNYC

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Hi, I have a bunch of ECN-2 film I've been shooting, and I had it x-processed in C-41 chemistry by a local lab, now it has a Rem-Jet backing, and the backing didn't quite come off so I soaked it in sodium carbonate to soften and dissolve the backing. (Don't worry I had the lab run two other normal C-41 rolls through to clean out their machine to ensure I didn't damage anything).

Now I haven't scanned the film yet, but to me it looks like portions of the film are solarized, I didn't notice this before (but I wasn't looking for it either) so since I did this in broad daylight, I wondered if somehow I caused an accidental reaction with the light and the sodium carbonate.

Anyone know?

I'll scan them after I finish developing some B&W sheet film. But it could also just be the x-processing that caused a color shift, but knowing this would be good in general for the future since I have a Kodachrome B&W project I'm working on (which also has a Rem-Jet backing).

Thanks!
 

Gerald C Koch

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No, there isn't any way to do this as the image has already been developed and fixed when the carbonate was used.

When you cross process film all sorts of "interesting" things can happen.
 
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VPooler

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I have done carbonate prebaths (Kodak even suggests it as an alternative to borax based bath in their technical publication about ECN2) prior to processing, although I processed it b&w, there were no hints of solarization or other unwanted artefacts. And I used a HEAP of carbonate, don't even want to know what the actual alkalinity was
 
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StoneNYC

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Thanks guys, yea it doesn't appear to be solarized by the look of the scans.

However they look awful, there's a sort of pink mucking all over the film, I think it's simply that it was processed at a walgreens, if I remember correctly they often look like that? But I could be wrong. Hmm, the colors aren't so bad...
 

Truzi

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LOL - you have to be careful of Walgreens. I had run around town(s) a bit to find the better drug-store minilab. Most of my stuff goes to a pro shop now, as the prices are not much more than Walgreens, and quality is far better.

For a test roll, however, I found a local Walgreens that does a fair job. Though I don't know the workers by name, I know what day to drop it off to get the most conscientious person running the machine. That said, what you see may actually be normal for cross-processing (I do not know, haven't tried it yet).
 

Rudeofus

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The pH of the final bath is important for color correctness, so a final bath in Sodium Carbonate may mess up the dyes that form the image. Try another bath in some soup that's well buffered around pH 6.5 and see what happens to the colors. A Sulfite/Bisulfite bath should work for this ...
 

Photo Engineer

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Do not use SULFIT/BISULFITE. This bath can cause degradation of the colors.

Use Acetic Acid/Sodium Acetate or Carbonate/Bicarbonate adjusted to pH 6.5

Follow it with a stabilzer bath of some sort.

And, just because your processing lab ran 2 C41 rolls after yours does not guarantee that the process is free of rem jet. Beware that others may get occasional black dots on their C41 films. I suggest that you not do this again or you will gain their undying enmity.

PE
 

Rudeofus

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Photo Engineer said:
Do not use SULFIT/BISULFITE. This bath can cause degradation of the colors.
Click to expand...
IIRC, every fixer contains Sulfite, and it's usually the final bath before STAB, so why would Sulfite suddenly destroy colors???
Photo Engineer said:
Use Acetic Acid/Sodium Acetate or Carbonate/Bicarbonate adjusted to pH 6.5
Click to expand...
Bicarbonate (without any Carbonate) won't go much below pH 8, so you won't reach pH 6.5 with a Carbonate/Bicarbonate buffer. Bicarbonate and Acetic Acid might get you there, but I'd love to hear an explanation why Sulfite could possibly cause problems ...
 
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StoneNYC

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Thanks, and yes Sir no more doing that, I should have run a control roll BEFORE the ECN-2 roll and 2 after, oh well, the pink marks do appear on the other films run by the lab too, but I recall often seeing that on my film as far back as my first roll, it's the same Walgreens I used back when I bought my film with my allowance and rode my bike to get it developed.

There was a lot of Rem-Jet left on the roll so I don't think much came off.

At least I know there would be a color image using C-41.

If I ever do that again I'll remove the Rem-Jet first.

I'll post images to show you in a few hours.
 

Photo Engineer

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Yes, fixers do contain Sulfite at very low concentration. About 10g/l or less. However, if he went much over that, it would be a problem, perhaps even at 10g/l because there are NO other chemicals present. Sulfite is a bleaching agent!

As for the Bicarb, you are right. I meant Bicarb + Acetic Acid or some combination like that to adjust pH.

Remember, Sulfite alone is bad for dyes and at pH values too low is death for some dyes.

PE
 
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StoneNYC

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Ok examples, heres the lab and a few other images, I didn't have a fluorescent light filter at the time so I DID do slight post correction on the white balance, but that shouldn't cause any issues with identifying any problems.






And finally, the "solarization" I saw seems to have been a color shift, not sure if this was the "beginning" or "end" of the roll (it was the end... But I don't know which end the machine started with to know if it's somehow their issue or something else... As you can see there's a blue tone to the top half of the frame, this was present in a fee images.

 

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AgX

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I would not call these artefacts solarisation.
Am thinking of a better term.
 

Photo Engineer

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A mix of bad processing and uneven removal of rem-jet. The white spots are rem-jet.

Also, there is fluorescent light in the pix. This is a difficult situation for any film to handle due to the discontinuous spectrum. Mixed with tungsten or daylight, it can cause a big problem with color casts across the image.

PE
 

VPooler

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Second on the spots being remjet. C41 can get acceptable results out of motion stock but proper removal of that gunk is an absolute must.
 
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StoneNYC

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I'll be scanning the other 2 rolls but I did scan about 3 images and they had a lesser amount of pink dots but nothing as bad.

Remember pentaxuser, this is ECN-2 x-processed in C-41, so I won't entirely blame the lab, but PE could comment on how different the two processes are?
 

Athiril

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I've done it through a frontier processor but with pre-removal of the remjet using a borax bath, I would gently rub the film between fingers wearing disposable nitrile gloves while under solution in a container, wash it out, then hang it to dry in dark room and respool into canister and process.
 

Photo Engineer

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ECN uses higher than 100F and CD3 instead of CD4 among other things. It also uses a Sulfuric Acid stop bath.

I don't think I should keep going. Too many changes!

PE
 
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StoneNYC

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Photo Engineer said:
ECN uses higher than 100F and CD3 instead of CD4 among other things. It also uses a Sulfuric Acid stop bath.

I don't think I should keep going. Too many changes!

PE
Click to expand...

Well importantly, could the difference between CD3 and CD4 cause those pink patches?
 

Rudeofus

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StoneNYC said:
Well importantly, could the difference between CD3 and CD4 cause those pink patches?
Click to expand...

Unlikely. Cross processing between E6 and C41 does essentially the same thing, using CD3 instead of CD4, and while the colors look a bit off, no E6/C41 cross processor has reported problems with the kind of spots you showed in your images. PE already explained that it's most likely the loose remjet backing in the C41 processing line causing this, and I sure hope it didn't affect other people who's film got processed on that day.

BTW I would advise against mixing a Bicarbonate/Acetic Acid buffer yourself, as its composition is uncomfortably close to the notorious Swedish Lemon Angels recipe ...
 
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StoneNYC

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Thanks, problem is I have no darkroom, so once the film is wet, I need to keep it in my daylight tank...

I'll just do it myself I guess.
 

VPooler

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Dump some soda in the tank among with water and a dash of dish detergent, the water should be warm. Let it sit for five minutes. Shake the hell out of the tank along all axises for a minute or two. Dump the water, note the dusty appearance of water. Fill the tank with water. Shake, dump repeat until the water is clear. Let the film dry on reel overnight. Wipe the backside with tissue paper to remove last of the remjet. Good enough, wind it back to cassette and go over to minilab. Do a last cleaning before scanning to remove last of the remjet. It should work but I have heard people reporting unusual color shifts - I have tried removing the remjet that way on a test strip and it works well but I haven't processed it so can't really tell about shifts as I will do the removal prior to ECN processing in the future.
 

Photo Engineer

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I don't recommend dish detergent due to other additives.

I don't recommend Swedish lemon angels as they use Citric Acid not Vinegar.

No, cross processing will not cause blotches or spots. Bad processing causes spots.

PE
 

VPooler

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Photo Engineer said:
I don't recommend dish detergent due to other additives.
Click to expand...
True, but if it is getting processed in C41 anyway...it helped to clear the remjet a bit better but a bit of elbow grease will do just the same. It should get wiped or squeeged down anyway before entering a minilab processor.
 
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StoneNYC

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Won't the emulsion be all puffy and get scratched by this process?
 
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