Processing K-12 film as B&W

[htmlguru4242]

OK-

I posted about identifying movie film on a previous topic. I've since determined that it's K-12.

Soo, I dont want to send it to Rocky Mountain Photo at their extremely high rates.

Does anyone know how this can be processed as a black and white negative or slide?

 

[dmr]

I am not a darkroom guru by any means, but I've been told that you can do this in more or less conventional B&W chemicals as long as you first remove the rem-jet antihalation backing. (How this is done will be an exercise for the student.)

You might take a short strip of it and test it first.

 

[Photo Engineer]

The rem-jet is removed with a sponge wet with dilute sodium carbonate solution. About 10% IIRC, but not sure. Run a test.

Negative processing will give an orange-yellow negative, and positive processing will give a near normal positive, but again a test is in order.

PE

 

[htmlguru4242]

Thanks, PE

Do you have any reccomendations for a developer to use?

 

[CRhymer]

Hello HTML,

I have done both neg. and reversal on K-12 and K-14, the K-12 and some K-14 found in old movie cameras, and some fairly recent K-14 Super8 (now discontinued) which I shot myself - also on some fresh 35mm Kodachrome 64.

Some observations:

The remjet is tricky to remove in the dark from a 25ft length of film - harder from 50ft of Super8. It can be removed after processing, but will gum up the grooves in your tank, and is difficult to clean off the emulsion side, should some get stuck there (through the sprocket holes, etc.) I spent two hours cleaning up (quite successfully) 50ft of Super8 K-14 with Q-tips and Edwal Anti-Stat Film Cleaner - but never again. It is a good idea to test a few inches of film in the light with sodium carbonate (Arm and Hammer washing soda) to practice removing the remjet.

Reversal, as PE said, will give you the best result. The disadvantage is what you see is what you get - unless you do some expensive copying/printing, but the latitude is pretty limited.

Negative processing, as PE also said, gives an orange-yellow cast which may be difficult to print through.

If you want to project the result, reversal will give you a very good image, if the original exposure and the first development time are correct and of course the film has not degraded too much over time.

You could send the processed negative to a lab and have a positive made (costly), but they may not be able to print well through the orange-yellow colour.

Alternately you could have it transferred to DVD and make adjustments on your computer.

For reversal, I use D-19 plus hypo for the first developer and dichromate bleach. The details are easily found online, or I can PM you the process. Ilford's reversal page is also a good guide. I used permanganate for some years - because I had it on hand and it is used in Kodak's T-max reversal kit. Dichromate has given me more reproducible results and has a long shelf life mixed.

Kodachrome 64 35mm (K-14) makes excellent B&W slides with D-19, although other films are cheaper and also give good results.

I believe you asked about film splitters. I bought one from J&C a couple of years ago in John's odds and ends section, although it is not a stock item. I buy my Foma R2x8 regular 8 movie film from him (best price - good service). I got a second one with a Lomo spiral tank.

If you have a 16mm projector, you can show your film before splitting, since the sprocket holes are spaced the same, only twice as many in 2x8. It will even work in an old double perf. 16mm projector. The result is quite unusual - one side running forward and the other backward. Also, the film gate is larger, but this is not a problem. It will give you an idea of what it will look like.

If you can not locate a film splitter on Ebay (or by asking John for a special order/contact whenever he finishes his move) a few labs will split and splice your film for a small fee. I have had some film (not Kodachrome of course) developed by the Black and White Film Factory (who also do split and splice for $ 5.00) with good result.

http://www.blackandwhitefilmfactory.com/

There are probably others in the US, which would save you postage, etc.

If you decide to go the negative route, I use D-19 straight, although I have never tried to print the result - it was strictly for testing purposes. Getting a 2x8 negative printed is rather dear - I suspect over $50.00. Others may have more info for this service.

At any rate, testing a few feet is essential. Although you will be loosing a bit of the start and end of the film, some of it will be light struck, which also provides information in testing pos/neg and fixing - the few frames you loose - assuming your first shot doesn't give good results - will probably be insignificant for the usual home movie.

Kodachrome is pretty high contrast IIRC (PE may have more info) and so is D-19 (you could try 9min 20C to start). This is not a bad thing for positives, but may not be ideal for negatives. You may want to choose a developer to limit fog (since the film is old). Donald Qualls suggested HC110 dilution G here:

Dead Link Removed

I have not tried it.

If this is a one-off and you don't want to get into reversal chemicals, you may find that projecting the negative image at 16mm gives quite an interesting effect, even with the orange/yellow colour.

Good luck.

Cheers,
Clarence

 

[htmlguru4242]

Thanks Clarence

I have dichromate bleach, but no D-19, though that'll be easy enough to find. How much hypo are you mixing with it, and do you have approximate dev times?

 

[CRhymer]

Hello htmlguru,

The hypo is not essential. I used to use no silver solvent at all. I usually use one now since the results are better (clearer highlights). There is a bit of discussion about reversal here:

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

and the Ilford Reversal page is helpful:

http://www.ilfordphoto.com/Webfiles/20061291034093.pdf

8-12 g/l is their range depending on the film. I wouldn't go more than 8g/l to start. Some have suggested this may add to fog. I did a roll of GP3 (Chinese film) 120 last night and used 10g/l. Nice result.

You can use Dektol if D-19 is not easily at hand.

I don't recall if you know that the film was exposed or if it has been rewound in the light. Most film I have found in old cameras is undisturbed unless the seller got curious. It seems that either the camera malfunctions and people put if away or the owner passes away/looses interest and the film sits there for years. You may find that the first few feet are light struck due to poor loading technique. I don't know how you plan to develop it, but I have found that the emulsion is easily scratched unless wound on some sort of spool. Short lengths 4 or 5 feet could be done by see-sawing. Splicing is fairly easy and splices are still available. Scotch tape will work in a pinch. You will also be able to adjust your development as you go.

At any rate:

D-19 for 10 minutes at 20C would be a good starting point. If there is anything on the film, you will see it. If you have dichromate bleach you are aware no doubt of the safety precautions. The second developer can be pretty much anything, since you will be developing to completion.

If you get a usable result, I would be glad to slit and splice it for you gratis, but since I live in the Northwest Territories of Canada, and only have surface mail here, it could be a long turnaround time.

Cheers,
Clarence

 

[Photo Engineer]

In order to get good cleanout (whites) in reversal films, it is necessary to develop the dmax silver in the negative development step to its maximum. This usually requires either a foggy emulsion or a foggy developer or both.

The way to achieve a foggy developer is to add a silver halide solvent to the first developer. This is done in both B&W and color processes. Hypo is not used except in rare cases due to formation of dichroic fog. (This BTW is one reason to use an acid stop bath in normal B&W processing - to prevent dichroic fog)

In any case, thiocyanate is often used as is another rare chemical called DTOD. Any silver halide solvent can be used, as long as it gives good whites in the reversal image and does not give gray blacks, which is sometimes a symptom of dichroic fog.

PE

 

[CRhymer]

Hello PE,

That is interesting. I have not noticed much difference between hypo and thiocyanate, but have never made a proper side-by-side comparison. Do you happen to know offhand what concentration of thiocyanate is likely to produce dichroic fog? I realize this may depend on the type of film and other compounds present in the developer. I use the developer one shot, so carry over is not a problem. I also happen to have a fair bit of thiocyanate on hand, so if there is a real advantage, I will switch. Can you say if there is any advantage in using dithiaoctane diol unless one is using permanganate bleach?

Thank you.

Cheers,
Clarence

 

[Photo Engineer]

Clarence;

Thiocyanate can also cause dichroic fog, but IIRC the level is about 1 g/l of developer. Kodak gives formulas for several reversal motion picture products on their web sites and if you look at them there are some good first developers given, even for color. You can see the chemical used and the amount used there. That might help.

You see, thiocyanate does not decompose as readily as hypo, and that is one reason why it is used. DTOD is useful as it does not decompose at all.

PE