direct positive film developing outfit

OK, I just bought a "direct positive film developing outfit" on eBay.

(That means it isn't here yet.)

 

It looks like the chemistry is in sealed foil packets, so dry, and

maybe more likely to still work than liquid packets.

 

But otherwise, it might be easier to replace the developers than some

of the others.

 

I knew about this when I was young, but they were out of my price

range. Now I get to try one out.

 

I do have Panatomic-X, which as I understand is the usual film to use

with this, but I might also be interested in Tri-X reversal 7266.

 

https://www.kodak.com/uploadedFiles/Motion/Products/Camera_Films/7266/Resources/7266_ti2617.pdf

 

I don't know how close it is to the chemistry that is normally used for 7266.

from Reversal film - Wikipedia

 

Black-and-white transparencies can be made directly with some modern black-and-white films, which normally yield negatives. The negative image is developed but not fixed. The negative image is removed by bleaching with a solution of potassium permanganate or potassium dichromate in dilute sulfuric acid, which is removed by washing and a clearing bath containing sodium metabisulfite or potassium metabisulfite. The remaining silver halide salts are re-exposed to light, developed and fixed, and the film is washed and dried.[7]

 

Black-and-white transparencies were once popular for presentation of lecture materials using 31⁄4" by 4" (31⁄4" square in the UK) glass-mounted slides. Such positive black-and-white projection is now rarely done,[citation needed] except in motion pictures. Even where black-and-white positives are currently used, the process to create them typically uses an internegative with standard processing instead of a chemical reversal process.

 

Black-and-white reversal films are less common than color reversal films.

 

a very long time ago, I did reversal process Panatomic x, but more recently I've done an internegative, or nowadays, do it digitally.

Edited October 31, 2019 by JDMvW

I have known the theory about how it works since I was fairly young.

 

I started darkroom photography when I was nine, and had, and still have the same

copy of, "Kodak Films in Rolls for Black and White Photography".

 

It includes the steps, assumes you will buy the subject of this thread, so doesn't

give details of the chemistry. I suspect that it isn't hard to find more details, though.

Some years ago, I did work in a chemistry lab so might have been able to get some

of the chemicals, and now I suppose I could mail order them.

 

Also when I was young, I bought something from Freestyle meant for making

black and white slides, as contact prints, which came in 8x10 sheets. I did try

it, but it never worked as well as I might have hoped. That was at the same

time that I bought 100 foot rolls of (ASA 40) Panatomic-X for $4.

 

When I was young, and couldn't afford color film, black and white was

conveniently affordable. Now it is more for the fun of it.

 

However, I might still try reversal processing of Super-8 Tri-X 7266, which

might not be quite right for this chemistry, but maybe close enough.

I now have another such kit, this one has the chemicals in cans, except for the redeveloper.

 

The first developer has powder and liquid, with the bottle inside the can.

The instructions have you partially open the can, dissolve the powder, then open

the can all the way to remove the bottle.

 

I now wonder if cans keep better than foil pouches.

 

Besides Panatomic-X, I also want to try processing some

Tri-X reversal Super-8 film with this, which I believe is close enough

to the suggested process.

 

More specifically, I want to process 10 foot strips of Super-8 film.

Never tried the reversal kit. I used to make black and white slides by contacting on Kodak Fine Grain Release Positive 5302 film. The stuff was remarkably inexpensive and handy around the darkroom for various masks and things. I remember it as less than ten bucks for 100' of 35mm, but times have changed.

It's easy to digitize B&W negatives, then invert and process the digital file with NIK and PS. The only film I've not been able to properly scan effectively in the past was Kodak's Kodalith, but if I can find the neg I'm sure it can be digitized effectively with my duplication setup.

While this thread's been brought to the surface, perhaps Glen could tell us how he got on with the kit?

 

As far as I remember, you simply use a contrasty developer for both first and second dev baths, and a ferricyanide bleach in between. Finishing off with a normal fixing bath.

 

The film needs to be capable of producing a high density, and I suspect T-max 100 would be quite suitable. You might need to use a clearing bath to get rid of the purple AH dye afterwards though.

I still haven't tried it.

 

I will try the first developer alone and make negatives, and see what those look like, first.

I believe that is D-67.

 

The second developer is a special fogging developer that has a short mixed life, so they

give you more packets of it.

 

I have Panatomic-X to use with it, one of the recommended films.

 

The newer kit is for TMax 100.

 

The kits I have don't come with a fixer, but they recommend Kodak Rapid Fixer.

Presumably clearing has the same problem as for negative films.

No longer available, but it was fun to use for making B&W positive slides in the 1960s...a product called Besseler Slide-O-Film. It was a coated plasticised sheet which you cut to the size of your negative, which was then exposed behind your negative either in a slide projector or in the sunlight for about 30 sec- 1 minute. You then took the exposed sheet (in the daylight, darkroom not needed) and dunked it in boiling water for about a minute to develop the image, which was clear -- giving a white to the projected image, or shades of white which blocked the transmitted light and produced gray--black when projected.

When I was younger, at the same time I bought 100 foot rolls of Panatomic-X (ASA 40) from Freestyle,

I also bought some 8x10 sheets that were supposed to be used for making slides. The only directions

it had was Dektol for 3 minutes. I did contact prints from 35mm negatives, cut them out and

mounted them in Kodak ready-mounts.

 

They never came out like I thought they should.

 

At that time, I already knew about the direct positive kit, but it was way out of my price range.

 

I think I was the only bidder on the ones that I now have.

The second developer is a special fogging developer that has a short mixed life, so they

give you more packets of it.

Easily replaced by a standard developer plus prior removal of the film from the tank and fogging it about a foot from a 100 watt lamp.

 

Also, contact printing standard negatives onto slow copying film isn't difficult. I did this in my mid-teens when some B&W slides were needed for back-projection in an amateur theatre production.

I also bought some 8x10 sheets that were supposed to be used for making slides.

Sounds like that might have been special duplicating film that utilised the solarisation effect. It was usually lith film that was pre-fogged to the point where its density would decrease with further exposure. Quite tricky stuff to use by all reports. I never had cause or chance to use the stuff, and I suspect it's no longer sold these days. While old stock will probably be unusable or unreliable.

Edited March 11, 2020 by rodeo_joe|1

 

(snip)

 

Also, contact printing standard negatives onto slow copying film isn't difficult. I did this in my mid-teens when some B&W slides were needed for back-projection in an amateur theatre production.

 

Yes, I think the material I had for doing it wasn't very good. There was no name

on the box, just the instructions for 3 minutes in Dektol.

 

It might be that the contrast was too low, and so they didn't look like they should.

 

Or maybe I just didn't try enough.

If you think about it, you're actually making a print on film. So using a print developer makes a lot of sense. Except you need twice the density of a print in the shadows, and hence twice the contrast, since the light only passes once through a slide, and twice, by both transmission and reflection, through a print emulsion.