Duplicating a color slide to BW neg

[Jim C.]

I've been spending way too much time in the darkroom, and I was wondering if
anyone has tried to duplicate a color slide on currently available film ?

[Mark Sampson]

BITD at Kodak, we used Tmax 100. Use a green filter, as all the resolution is in the green layer.

[Gary Beasley]

Do you have to develop the neg to any higher contrast than usual to get the optimum result?

[LabRat]

Do you have to develop the neg to any higher contrast than usual to get the optimum result?

No, a slide is contrasty enough, so a normal straight (bracketed) shot will usually do...

Steve K

[ic-racer]

In the past I have put the slide in an enlarger and a film holder with b&w film on the baseboard. Prop up on edge a little to make the film holder level. I use 'white' enlarger light and panchromatic B&W film.

[Jim C.]

BITD at Kodak, we used Tmax 100. Use a green filter, as all the resolution is in the green layer.

BITD ?

Interesting, I was thinking along the lines of using filters to keep the exposures times down
but never thought of using them for resolution.


No, a slide is contrasty enough, so a normal straight (bracketed) shot will usually do...

Steve K

You lost me there with 'bracketing' in a darkroom setting.


In the past I have put the slide in an enlarger and a film holder with b&w film on the baseboard. Prop up on edge a little to make the film holder level. I use 'white' enlarger light and panchromatic B&W film.

For my initial test I did the same thing, but instead of a film holder I used the raised edges of my enlarging
easel to locate the film and a sheet of glass to hold the film flat.
Grossly over exposed :)

[LabRat]

Oh, Jim...
I usually "downshoot" a chrome by copying with a camera, with the chrome on the lightsource, or mounting a camera on the enlarger column with an arm, (aiming up) and letting the enlarger lens project onto the film (into the camera) to "shoot" smaller format negs... (I get to use a TTL meter that way!!!) I'll bracket then...

And I keep an old, leaf shutter (from my MP-4 rig) with adapters for the enlarger lenses in the lab, so I can time short exposure process stuff... (or keep the enlarger lens closed while I'm letting a cold light head warm up, or to "cook" problem negs in glassless carriers (so they "pop" properly...)) So some step test exposures there, too... Handy!!!

Steve K

[vinny]

Bitd= back in the day.
Bracketing? That's where you make multiple exposures using different settings to guestimate proper exposure rather than developing one sheet only to realize your exposure was off.

[bob carnie]

Hi Jim

One method that is being done by many workers is to have a LVT negative made. This is not new technology in fact it has found a resurgence. Specifically for digital only capture workers who then want to
make a silver gelatin print, or cibachrome, from 4 x5 or 8x10 film and have it printed on paper of choice via enlarger. ( this allows them to print silver with their current digital capture methods.)

This practice is very popular by Salgado right now.. I have seen many projects done this way, I prefer the method I describe below as it is a contact print and I believe sharper final product.

For your purposes you could scan the neg and the BW coversion and make a neg to any contrast and density you require for your darkroom. There are people here that can make this neg here and may chime in .

I am making very large silver negatives for many end processes, the largest neg I have made was 24 x36 inch for a series of lith prints we made on Ilford Warmtone. Once again we are scaning the original
negative (colour or black and white) and via PS and my image recorder (Lambda 76) enlarged tailor made negs are produced. - I am not offering this service commercially but I do it for my self and a few clients
who I work with on large shows. The price per single unit is too outrageous to offer to clients , but when spread over a 30 print show it becomes affordable(somewhat).


Bob

[Jim C.]

And I keep an old, leaf shutter (from my MP-4 rig) with adapters for the enlarger lenses in the lab, so I can time short exposure process stuff...


LOL, while collecting hardware for my darkroom I got a lens board for an Elwood that had a Ilex shutter, I remember thinking
that it must have been used as a timer for exposing, I stored that tidbit in the recesses of my brain, along with the shutter, when
I decided that I wanted to do a enlargement of a slide, exposure came up as a problem, your mention of a leaf shutter
brought it back.

I guess Fixer fumes can affect memory ! :)

Vinny, Thanks for the BITD definiton. I do bracketing with 35mm and 120, but with sheet film not $o much

Bob, Thanks for the info on LVT negatives, I'm more interested in experimenting with
non digital methods of making a neg from slide. It makes it much harder since from what I've gleaned
off the Intarweb, Tech Pan was the recommended film to use, but that's history now.
Good info on LVT negs nonetheless.

[Jerry Bodine]

Back in the early '70s I had an E3 Ektachrome 4x5 that I thought might be better in b/w (didn't have b/w film with me when it was shot). So I laid it on my 5000K Macbeth lightbox, masked it, and set up my Sinar Norma with 55P/N to get an instant negative. It worked well enough to get a decent 16x20 print.

[blindpig]

Still another voice.
There are two problems with duplicating you are going to have to address,sharpness and contrast(I guess dust would be a third,sorry).Personally, projecting the image would be my choice as lens flare while detrimental to apparent sharpness will help lower apparent contrast( the difference will be negligible unless your lens is of low quality or extreme enlargements are to be made) and will allow burning and dodging adjustments if necessary. Pre-flashing the dupe film might help as well.Finally adjusting your processing to a lower contrast could be effective.
Good luck,
Don

[Drew Wiley]

You treat your slide just like a scene in nature which you can selectively balance or edit via colored filters if necessary. It takes some practice with your particular light source and chosen film to do a good job of this; but once you learn, it's fairly easy to repeat. You can either do this by projection or contact, with an appropriate lens on the enlarger. You want a long-scale film and developer. You could use FP4 or one of the TMax products and HC-110. I have person developer tweaks and can control contrast very precisely via unsharp masking, but that is an acquired skill set and mandates special registration equipment. I never flash. This can be a fun kind of project if you are patient and nitpicky about cleanliness. If you do a contact, you want either antinewton glass in the frame, or a slip sheet of frosted mylar between the glass and base of the film to prevent rings. Exposure is made emulsion to emulsion. Projection is a bit more difficult. I recommend a vacuum filmholder on the easel, and a very precise glass carrier with AN glass, and an enlarging lens suitable for small degrees of magnification with your given format. There is a distinct learning curve. If none of this appeals to you, have it scanned and digitially output by someone like
Bob, who has the right tools and experience.