Mixing developer/bleach/fixer etc. from sratch: video to show process?

Dcarubia · Jun 3, 2015

I've read quite a few discussions on APUG regarding the mixing of color developing chemicals from scratch.

For someone who has not gone beyond developing film with a Unicolor 3 step process, it all seems rather a complex process.

I'm sure for those of you who've done it a few times I'm sure it's easy peasy for you.

So I can get a better idea of what it's like and whether it's too much work for me to want to bother, I was wondering, does a video exist showing the process?

As an example, how does one mix an ECN-2 color developer from scratch? What is the process involved in taking a PH reading accurately? Maintaining temperature? Is there a specific way to safely handle chemicals?

I know I can read about all this and I have. My question is: does someone have a video of the process they go through? If one doesn't exist, could somebody create a video on their next mixing session and post it?

(Yes I have looked on APUG and elsewhere for a video and have not found one.)

Gerald C Koch · Jun 3, 2015

If you have never mixed your own B&W solutions then your wish to mix your own color chemistry will be quite difficult. There are videos on the internet on how to mix B&W developers. Watch these first to see if you will be comfortable with what needs to be done.

If you are confident that you can mix B&W chemicals easily then for starters read the following, Kodak Publication No. H-24, Processing Motion Picture Films, Module 7: Process ECN-2 Specifications.

Many of the color processing formulas contain chemicals that are not readily available to the public. You can usually find substitute or unofficial versions that are better for your use.

You will need a scale which can measure amounts at least to an accuracy of 0.1 g. Which means that the scale must display amounts to TWO decimal places. Also needed a 1 liter and a 10 or 25 ml graduates. Kitchen measuring cups are not a satisfactory substitute.

While a pH meter would be helpful it is not necessary.

The following formula is a simplified recipe for the ECN-2 developer. It makes substitutions for had to obtain chemicals.

Kodak SD-39 (Unofficial)

Distilled water (35°C) …………………………………………… 750 ml
Sodium sulfite (anhy) ……………………………………………… 2.0 g
Benzotriazole, 0.2% …………………………………………………… 10.0 ml
Potassium bromide ………………………………………………………… 1.4 g
Sodium carbonate (anhy) ………………………………………… 25.6 g
Sodium bicarbonate ……………………………………………………… 2.7 g
CD-3 …………………………………………………………………………………………… 4.0 g
Distilled water to make ………………………………………… 1.0 l

Weight out each chemical IN THE ORDER GIVEN and dissolve it. Finally add enough water to bring the total volume to 1 liter. It is important to use water of the temperature specified to insure that chemicals will dissolve easily. Decant the liquid into a glass or PET plastic bottle and label it with the contents and date of mixing.

Good luck.

RPC · Jun 3, 2015

Gerald C Koch said:
While a pH meter would be helpful it is not necessary.

I don't know about the ECN-2 formula, but some formulas for C-41, RA-4 and E-6 need to be adjusted to the proper pH after mixing to get the best results.

Gerald C Koch · Jun 3, 2015

RPC said:
I don't know about the ECN-2 formula, but some formulas for C-41, RA-4 and E-6 need to be adjusted to the proper pH after mixing to get the best results.

Having mixed many color processing solutions (C-22, C-41 E-3. E-4, E-6, ECN-2) with excellent results I have never had the need to adjust pH. (I am also very fussy about color balance.) Commercial processors might experience a pH drift with continued use and replenishment but this may not be the case for the home user. However this does require weighing out chemicals carefully.

Dcarubia · Jun 3, 2015

I've read a few Kodak ECN2 manuals and a bunch of posts here on APUG on scratch mixing. Reading about something is different that doing it and experiencing it.

I took your suggestion and looked for B&W developer scratch mix video's, but I could not find any. I did find a bunch of videos on mixing from concentrated prepackaged kits, which I have done before.

So, my request remains: if in the course of scratch mixing any film chemicals (preferably with use of scale, PH meter and specific gravity meter) one of you would be so kind to video tape it and post it here or on You-tube, so I can get an idea of what it's like to do all this work, I (and I'm sure others) would appreciate it and find it very educational.

Gerald C Koch · Jun 3, 2015

You might look on some of the alternative photography sites for actual videos. Making cyanotypes, salted paper, emulsion, etc. Here are a few sites with fairly detailed information
http://unblinkingeye.com/Articles/Developers/developers.html
http://photo.net/learn/darkroom/making-your-own-black-and-white-chemistry/
http://www.ephotozine.com/article/mix-your-own-chemicals---traditional-darkroom-ideas-4636
http://jbhphoto.com/blog/2012/02/06/mixing-your-own/

Xmas · Jun 3, 2015

Dcarubia said:
I've read a few Kodak ECN2 manuals and a bunch of posts here on APUG on scratch mixing. Reading about something is different that doing it and experiencing it.

I took your suggestion and looked for B&W developer scratch mix video's, but I could not find any. I did find a bunch of videos on mixing from concentrated prepackaged kits, which I have done before.

So, my request remains: if in the course of scratch mixing any film chemicals (preferably with use of scale, PH meter and specific gravity meter) one of you would be so kind to video tape it and post it here or on You-tube, so I can get an idea of what it's like to do all this work, I (and I'm sure others) would appreciate it and find it very educational.

You may be being too cautious.
Think of it like opening a can of beans, emptying beans into saucepan, heating pan,...
However wear rubber or nitrile gloves and safety glasses.
I always work with liquids, scale, & powder in bath tub to allow for easy address of spillage.

Don't have pH meter or hydro...

Gerald C Koch · Jun 3, 2015

The only times that I have used specific gravity values was when I was trying to duplicate a commercial developer. What I did then was to weigh a 10 ml graduate empty and then again with the solution. The Sp Gr is 1/10 of the increase in weight. In the lab one would use a weighing bottle but they are expensive.

Dcarubia · Jun 3, 2015

Xmas said:
You may be being too cautious.

I wouldn't say I'm cautious. More like I want to get a feel for the amount of work (and possibly hassle) involved to come up with the appropriate developer/stop/fix etc. to scratch mix my own photo chemicals to see if it's worth it.

I recently cut some Kodak Vision 3 50D 65mm (yes, with a "6") film down to 61mm, rolled it up onto a 220 spool and took some pretty nice photos with it. (Let me tell you, it is not easy to cut 2mm off of of each side of a 65mm roll of film straight enough to roll it up on a spool and work in a camera.) If you think 50D is nice with 35mm, give it a try in medium format!

I developed it with C41 a UniColor kit. The colors that came out of it were pretty decent, but at some point I'd like to use the proper chemistry to make sure the dyes are stable, etc.

Gerald C Koch · Jun 3, 2015

If you buy a good balance then take care of it. Chemidcals should never touch the pan. Use paper muffin cups or squares of paper. Remember to get the tare of anything you use so it's weight is not included in the total.

VERY IMPORTANT always read the MSDS sheets for each chemical you are using. Always use goggles, gloves and insure proper ventilation when weighing and mixing.

Xmas is right this is not rocket science. But it is work and involves a fairly high initial cost for chemicals, scale, etc. You would have to weight the cost depending on how much you shoot. Certain color chemicals notably the developing agents are expensive. They also do not keep very well, not like most B&W ones. Realistically for a few rolls a month (say 5 or less) I wouldn't bother.

Xmas · Jun 3, 2015

Gerald C Koch said:
If you buy a good balance then take care of it. Chemidcals should never touch the pan. Use paper muffin cups or squares of paper. Remember to get the tare of anything you use so it's weight is not included in the total.

VERY IMPORTANT always read the MSDS sheets for each chemical you are using. Always use goggles, gloves and insure proper ventilation when weighing and mixing.

Xmas is right this is not rocket science. But it is work and involves a fairly high initial cost for chemicals, scale, etc. You would have to weight the cost depending on how much you shoot. Certain color chemicals notably the developing agents are expensive. They also do not keep very well, not like most B&W ones. Realistically for a few rolls a month (say 5 or less) I wouldn't bother.

Hi Gerald

If you are using ECN you are going to have to scratch mix?

My scales resolve 0.01 gm but were cheaper than 1kg of KOH!

Noel

Gerald C Koch · Jun 3, 2015

Xmas said:
Hi Gerald

If you are using ECN you are going to have to scratch mix?

My scales resolve 0.01 gm but were cheaper than 1kg of KOH!

Noel

Some people cross process ECN films in C-41 chemicals. Cinestill has made a business of selling ECN films minus the Rem-Jet coating for C-41 processing. There is some cross-over but some people except this.

Xmas · Jun 3, 2015

Gerald C Koch said:
Some people cross process ECN films in C-41 chemicals.

I read post #5 different?

RPC · Jun 4, 2015

Gerald C Koch said:
Having mixed many color processing solutions (C-22, C-41 E-3. E-4, E-6, ECN-2) with excellent results I have never had the need to adjust pH. (I am also very fussy about color balance.) Commercial processors might experience a pH drift with continued use and replenishment but this may not be the case for the home user. However this does require weighing out chemicals carefully.

As they say, YMMV.

I have tried several C-41 formulas and an RA-4 and in every one the pH was high after mixing (even using distilled water) and gave either noticably high contrast or crossover. Adding some acid to bring the pH down solved the problem. This reflects the experiences of others who have mixed their own, like here:

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

I am surprised that you haven't had the problem, you must have used just the right formulas. In any case the OP should be aware of the potential for this situation, and have a pH meter on hand. As touchy as color chemistry is, one shouldn't take chances.

Xmas · Jun 4, 2015

RPC said:
As they say, YMMV.

...

I've not used a pH meter for c41 (kits or scratch) either.

Never got scratches from squeegee or bromide drag etc. either always different problems.

RPC · Jun 4, 2015

I also use a densitometer and gray scale to check my results and it has been most helpful in seeing what a formula is actually doing, and this is where crossover and improper curve shape can be easily detected.

Gerald C Koch · Jun 4, 2015

Unless one is experienced in mixing solutions it is easy to make the wrong assumptions when reading a formula. The listed pH value is based on using the correct chemicals. It represents what would be typically seen by someone mixing the formula using the chemicals listed. It serves two purposes. First, as a check that the formula has been compounded correctly. Second, that in a replenishment system it provides data for adjustment with acid or alkali with use. If any initial adjustment were needed it would be given in the formula. Similarly the specific gravity is also a check for correct mixing. In this case however there is no adjustment possible.

When the pH is incorrect it can sometimes be attributed to using the wrong form of a chemical. For example sodium carbonate is readily available in two forms, monohydrate and anhydrous. Using the anhydrous form will result in a higher pH unless that amount used is adjusted. Another example would be using technical grade TEA instead of the 99% pure grade. Some chemicals are not stable. Sodium bicarbonate will lose carbon dioxide gas and be converted to sodium carbonate increasing its pH. Adjustments are also required when substituting between potassium and sodium salts.

For anyone experiencing difficulties I suggest reading either the labels or the MSDS sheets for every chemical listed in the formula.

Cheap pH meters are often not very accurate. Any pH meter should always be checked routinely against the known pH of a buffer solution. In a lab the pH meters are checked again two buffer solutions near the ends of the electrode's range.

Substitute formulas given on the internet must be looked at with some suspicion. They are not subject to the same rigor as the official ones. If possible use the official formulas.

Dcarubia · Jun 4, 2015

Let's say I decide to keep it simple and am happy with the colors I get with C-41 (vs. ecn2). Does anyone have any idea of how long it would take before I start seeing noticeable (by eye) color shifts (dye stability) after film has been developed?

Are we talking Years, months, weeks or days?

Gerald C Koch · Jun 4, 2015

Dcarubia said:
Let's say I decide to keep it simple and am happy with the colors I get with C-41 (vs. ecn2). Does anyone have any idea of how long it would take before I start seeing noticeable (by eye) color shifts (dye stability) after film has been developed?

Are we talking Years, months, weeks or days?

The color shifts are immediate and are caused by different color developing agents used for the two systems creating slightly different color dyes. To see results of ECN films in C-41 google on Cinestill films. There lots of examples. The dye stability should be about the same.

I personally am not impressed with the results but other people may not have this problem.

Mixing developer/bleach/fixer etc. from sratch: video to show process?

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