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michaelbsc
01-01-2011, 09:00 PM
Michael;

In practice at EK, we do work with what amounts to B&W single layer coatings. The problem is that a multilayer version acts differently due to diffusion. That bugaboo changes everything. The end result though is that whatever you do with whatever process and coating, your final result will be OK if you can produce a neutral step wedge from a 3 color exposure.

PE


Am I correct in the assumption that by isolating the three color development steps from one another I can simply totally fog the sheet for each step without concern for the reexposure, thereby removing that variable from those experiments?

MB

Photo Engineer
01-01-2011, 09:06 PM
Michael;

If it is an integral tripack, then you cannot fog the sheet. If you use separation exposures on 3 sheets of B&W film, then you can fog the sheet.

PE

happyjam64
01-01-2011, 11:11 PM
Toasting in potentially epic bread!

This is actually quite interesting, it's starting to look as though kodachrome may become a cottage industry.

michaelbsc
01-02-2011, 01:14 AM
Toasting in potentially epic bread!

This is actually quite interesting, it's starting to look as though Kodachrome may become a cottage industry.

I'm not sure that one could say Kodachrome per se will become a cottage industry. But certainly hand processing Found Kodachrome is possible even if difficult.

I think the best option would be http://www.kodachromeproject.com/forum/showthread.php?t=674 over at the Kodachrome Project.

But that might be more than can actually get done. And anything we're doing here can only help his effort as well. Kittlegraphy has got to get the chemicals, and helping figure those out can only provide support to get his machine going.

(Kind of ironic, to process Found Kodachrome on a Found K-Lab.)

I wonder about his volume requirement, however. Finding 25 rolls to process at a time might be easy the first year - once word gets out that you can still do it. But after that I think it will dribble in one or two rolls at a time for several years. That might be tough to sustain. Remember, there's no more new being made.

As far as duplicating Kodachrome emulsion in a home darkroom goes, well sure, anything is possible. But it's going to be fraught with failures and cost a lot. PE estimated no better than a 20% yield, and I think he's being kind. I doubt you could get 5 out of 100 good coating passes until you had spent yourself and your children into debt for life. Maybe if you will the lottery you'd have enough money to get it right.

As many also know, Kodakchrome is a B&W film, not a color film, so technically a modern manufacturer like Ilford could coat a replacement. But the R&D would make it unprofitable. Remember, it's already fail with Kodak.

TerryM has stated that he's working with someone to coat a new version, and I wish him all the luck in the world. If it goes well, not only will Kittlegraphy have feed stock for his K-lab, but I expect many would do home development exactly as we're talking about here. While it's more involved that E6, it isn't that much more involved, or at least so it seems.

michaelbsc
01-03-2011, 10:53 AM
Michael;

If it is an integral tripack, then you cannot fog the sheet. If you use separation exposures on 3 sheets of B&W film, then you can fog the sheet.

PE

OK, to make the three sheets for simulating the three color layers I need a #25, a #47B, and a #58 filter.

This is correct?

MB

Photo Engineer
01-03-2011, 10:58 AM
If you use 3 sheets for exposure in-camera, you need something like that. For reexposure during processing use just white light.

I had recommended to me the use of a WR98, 99 and 70 filter set for in-camera use and for enlarging using separation. But any good tricolor filter set is OK.

PE

michaelbsc
01-04-2011, 12:52 PM
If you use 3 sheets for exposure in-camera, you need something like that. For reexposure during processing use just white light.

I had recommended to me the use of a WR98, 99 and 70 filter set for in-camera use and for enlarging using separation. But any good tricolor filter set is OK.

PE

I talked to Sandy King, and his suggestion is to use the narrow band filters for separation of existing slides with an enlarger, but use the wider filters - #25, a #47, and a #58 - for in camera separations.

I may not be able to tell the difference, but that's his standard practice.

If nothing else it's a starting point. All I really need for now is three colors to practice with.

MrCoffee
01-05-2011, 02:11 PM
I am curious about the K-14 process after the initial developer. Watching a news cast that showed the machine at Dwayne's in operation, I saw what looked like film coming out of a yellow dye, and then looping into another tank. If so, does that mean that part of the Kodachrome process could be done in regular light, before the fixer? In other words: Is the initial developer before the color developers the only parts that required total darkness?

Photo Engineer
01-05-2011, 02:35 PM
Darkness is required until the last (magenta) developer. There are 2 re-exposures, red then cyan development and blue then yellow development and then a fog or white light step with magenta development. The 3 color developers are unstable and quickly become highly colored. That is probably what you saw. And if the lights were on for the yellow development,the film was being ruined.

PE

MrCoffee
01-05-2011, 05:25 PM
It may have been the fogging just before the magenta developer, then. Thanks for clearing that up, PE.

MrCoffee

Photo Engineer
01-05-2011, 05:27 PM
Well, actually, the fogging is done chemically in the magenta developer, but the process could have been light by then.

PE