CD-3 substituted with CD-4 (per Photographers' Formulary catalog)?

[tranquibra]

I'm interested in some ECN-2 process at home. I noticed that Photographers' Formulary catalog (http://stores.photoformulary.com/images/store_version1/Catalog.pdf, page 27), for CD-3, it says "use CD-4" instead. I remember I read past posts, including some from PE, that CD-3 and CD-4 are meant for different dye formation and cross using them will cause color shift.

I know CD-3 is also available from Artcraft Chemicals. But from a practicality point of view for ECN-2 process and your experience, can CD-3 really be substituted with CD-4 without affecting the final dye color rendering and stability? If so, what would be a good weight conversion? Kodak publication calls 4g/L for CD-3.

Thanks for your help.

 

[Athiril]

CD-4 cannot be substituted in place of CD-3 for dye stability on films designed for CD-3, the dyes produced are 'slightly' different, not the stable intended forms.

Also you must run a formaldehyde/formalin stabilising bath with ECN-2, stabilisers are not built into the film like C-41.


As far as colour rendering, different dyes formed, can never be identical. Other than that, you can still achieve quite good colour results (this isn't the same as simply running it through C-41 though).

I put some 5201 50D through a split-bath CD-2 developer which came out very nice, along side with some ECP-2 print film (CD-2 native), as a baseline comparson (trying to get a daylight pictorial developer for ECP-2).

4g/L CD-3 should be 2.24g/L CD-4 for equivalent development iirc.



Also the ECN-2 kit developer, parts A, B are inexpensive, though you have to handle a 20L cubi container for part A, which can be annoying.

Starter is also inexpensive in the U.S. as well iirc.

 

[tranquibra]

Thanks for your reply, Athiril. The film I will shoot with is 5219. I'm planning to do negative development at home, then scan negatives and order prints online or local store. For B&W, I do all the work by myself in the traditional wet darkroom at home.

I asked if CD-3 can be substituted by CD-4 because I want to keep my base raw chemical stock to the minimum. I have neither at this time. Maybe I should stick to the official ECN-2 formula published by Kodak, minus anti-fogging agent.

Anyone knows how good the CD-3 dry powder keeping property is? I'm also planning to store ECN-2 developer working solution (mixed with distilled water) in amber lab glass bottle, filled to rim. Not sure how long I can keep it fresh, maybe at least a couple of months? I did check the Kodak's ECN-2 kit, but the total volume it can make is way beyond what I can consume in a reasonable amount of time before the concentrate goes bad. Also shipping cost for the heavy liquid solution will make a deep dent on my budget.

 

[Athiril]

Thanks for your reply, Athiril. The film I will shoot with is 5219. I'm planning to do negative development at home, then scan negatives and order prints online or local store. For B&W, I do all the work by myself in the traditional wet darkroom at home.

I asked if CD-3 can be substituted by CD-4 because I want to keep my base raw chemical stock to the minimum. I have neither at this time. Maybe I should stick to the official ECN-2 formula published by Kodak, minus anti-fogging agent.

Anyone knows how good the CD-3 dry powder keeping property is? I'm also planning to store ECN-2 developer working solution (mixed with distilled water) in amber lab glass bottle, filled to rim. Not sure how long I can keep it fresh, maybe at least a couple of months? I did check the Kodak's ECN-2 kit, but the total volume it can make is way beyond what I can consume in a reasonable amount of time before the concentrate goes bad. Also shipping cost for the heavy liquid solution will make a deep dent on my budget.

You might want to consider adding a chelating agent to the ECN-2 recipe.

 

[tranquibra]

I will keep that in mind. Thanks.

 

[cinejerk]

5219 has a rem jet coating. You will want to get that off or it will make a mess of your chemistry.
You need an alkaline bath of some sort. Lots of info searching here.

(there was a url link here which no longer exists)

 

[Photo Engineer]

And, I have mentioned that CD3 vs CD4 thing to the Formulary. It has not changed. I'll have to mention it again.

PE

 

[tranquibra]

PE, thanks for bringing attention to the Formulary. Hopefully they will make correction soon. I was always fascinated with chemistry when I was a little kid and did experiments at home. Of course, my mother could tell what I did by holes left on windows curtain from sulfuric acid.

cinejerk, thanks for your reminding of the rem-jet. I plan to use washing soda+baking soda alternative as given by Kodak for pre-bath before development. I don't have water jets to blast the rem-jet away, so I will give 2 mins for pre-bath followed by vigorous washes instead until the water is clear.

I'm still on the planning stage, and here is the general sequence I'm planning to use:

[1] washing soda+baking soda based pre-wash - 2 mins @ 80F
[2] repeated vigorous wash until water is clear @ 80-100F
[3] cd-3 based developer - 3 mins @ 106F
[4] citric acid based stop bath - 0.5 min @ 80-100F
[5] wash - 0.5 min @ 80-100F
[6] ferricyanide based bleach - 3 mins @ 100F
[7] wash - 1 min @ 80-100F
[8] two bath fix - 2x1 mins @ 100F
[9] wash - 2 mins @ 80-100F
[10] formaldehyde+jet dry final rinse - 10 secs @ 100F

 

[Photo Engineer]

You know that Kodak has posted the ECN process sequence and formulas on their web site.

Those are the best to use.

PE

 

[tranquibra]

Yes, Kodak's publication is definitely great! My plan is based on ECN-2 process on Kodak's web site with only minor adjustment, like on the stop bath and two bath fixer.

 

[hrst]

cinejerk, thanks for your reminding of the rem-jet. I plan to use washing soda+baking soda alternative as given by Kodak for pre-bath before development. I don't have water jets to blast the rem-jet away, so I will give 2 mins for pre-bath followed by vigorous washes instead until the water is clear.

Vigorous agitation doesn't seem to work, at least for me. It needs some kind of physical contact, either with high-pressure water jets and/or rotating buffers.

In a hand process, I just drag film between my fingers (with nitrile gloves) a few times. My procedure is like this:
1) baking soda solution for a minute or two
2) drag film between fingers in a fresh water bath
3) repeat (2) in a new fresh water bath
4) (optional) -- repeat once more to make sure all remjet is removed.

This procedure may scratch the film and has a risk of redepositing remjet on the emulsion side. The risk of redeposition is decreased but the risk of scratching is increased if you increase the number of repeats, so pick your poison .

 

[Athiril]

For remjet - vigorous agitation causes it to fall off of some films, and only a little of some other films (5201 50D for example).

In any case, with a few goes at that, anything left on the film should not come off in processing with less vigorous agitation, you can clean it off near the end, before last rinses.


I also finger squeegee with nitrile disposable gloves. I do not recommend to do it bare handed, as you will likely wipe oil all over the film from your skin.



I haven't scratched film doing this, I have scratched films almost every time with a film squeegee. After each wipe, rub fingers in water to clean gloves. You can tell when the film is clean when your finger-squeegee'ing is perfectly clear.


You could also do it in a bucket of water, while the film is in solution, touching the emulsion side, while only rubbing the back of the film.

 

[newcan1]

Artcraft sells CD3

I have to say, after developing many rolls of ECN-2 in a regular plastic developing tank, I never get optimum results using 4g/L of CD-3. I use about 5.2g/L for best results. I don't know why that is, and I had a "developer quest" thread on here for a while, and while I hate to deviate from official formulae, I keep coming back to around 5.2 to 5.4g/L CD-3 for best results. Maybe it's because some of the stocks I am using are quite out of date, but not all of them are, and I always get thinnish negatives with just 4g/L.

 

[newcan1]

Oh and with remjet, with Kodak stock, I always wait to the end to remove. I only use water for a pre-bath, and I find a quite long pre-bath (about 3mins) seems to help with optimal deveopment (measured anacdotally, but I seem to get a petty good color balance if I start with a long prebath).

Also - I use very long washes between stop and ferri bleach -- maybe 4 or 5 changes of water 30 secs each. No matter what, the rinse seems to be pink with less than that, which I would attribuite to CD-3 - even if I use a clearing bath in between. I would hate to have that carry to the bleach.

 

[Photo Engineer]

The carbonate rem-jet step makes the film alkaline. This probably accelerates development a bit don't you think? That might account for your weak slides.

Another thought is that CD4 (and all CDs) come as 2 or 3 different salts. Original CD3 was the Sulfate salt. Sometime a few years ago, they changed to the p-Toluene Sulfonate salt with a vastly different molecular weight.

Those are two thoughts OTOMH.

Older CDs such as CD1 and CD2 came as Hydro CHloride salts and then changed to Sulfate salts.

BTW, the Formulary web site has been changed to omit the suggestion to use CD3 for CD4 and CD4 for CD3.

PE

 

[newcan1]

I'm going from memory but I think the carbonate remjet step is only 10 sec or so and probably a rinse afterwards. it may accelerate development a bit but I don't think much. I have used a carbonate pre-bath with Fuji stock as their remjet tends to melt away in the developer stage, and using an alkaline pre-bath causes it to melt before the developer (and hence not mess it up). I don't think that changes my analysis, that I at least get better results with a bit more CD3. It could be the molecular weight change, especially if Kodak didn't update its formula. Very interesting!

 

[Photo Engineer]

I'm saying that you are not using the EK process. Any number of things can change results.

PE

 

[tranquibra]

The carbonate rem-jet step makes the film alkaline. This probably accelerates development a bit don't you think? That might account for your weak slides.PE

+1

This procedure may scratch the film and has a risk of redepositing remjet on the emulsion side. The risk of redeposition is decreased but the risk of scratching is increased if you increase the number of repeats, so pick your poison .

I have been mulling practical options to remove remjet without having to take either poison. Here is one in I just came up yesterday. How about an ultrasonic cleaner, like those small ones for jewelry cleaning as long as it can hold a single film reel inside. The softened carbon deposit should come off easily without any physical scratch. If anyone happens to have one at home, would you please give it a try and let us know if it works?

The bright side of my planning is that finally I got a dedicated film scanner for ecn-2 negative. I don't have a real color sample yet, but here is a b&w one (fuji400 in 510-pyro).

 

[newcan1]

I use printer's 4 inch cotton pads to remove the remjet under warm running water at the end of the process. I have never had a problem with scratching the film. I just gently rub the pad on the back of the film under the running tap, moving along slowly, holding the rubbed part in my hand. I then even gently rub the emulsion side, then the reverse again for completeness. The pads are very soft and I have never had a problem.

 

[tranquibra]

Finally I got chance to develop my first roll of color film in my life via ECN-2 process as published by Kodak using CD-3. I did make a mistake by overdeveloping the film a little bit (time & agitation). The temperature control is not too bad in a water bath and it does take time however. I only rinsed rem-jet 3 times after pre-bath and didn't wait until the water became totally clear. So there are a few visible specks in the scan (Mädchen Orchid). The ICE was on for the other three (Lady Eggplant, Mr. Bean and Baby Cucumber) and the rem-jet specks are significantly reduced if not totally eliminated. There is no other post-processing except for image rotation, size scaling and a little cropping.