printing on positive transparency with enlarger

Hi,

I have 35mm colour negative image that I am trying to print onto strips of colour transparency film. My background is in filmmaking so I am using 35mm motion picture colour negative film and printing onto 35mm colour positive film, processing with ECP 2D. I understand these materials and do not have a problem. However, I am not a photographer so I do not have much darkroom experience. The enlarger I am using is a Beseler that does not have a colour head. What I am trying to achieve is to enlarge the 35mm original onto strips of 35mm positive that are butted together on the easel; this produces a large positive image. I am using CC filters in the enlarger but not any contrast filters. I put black paper on the easel so light does not reflect through the base of the film. My problem is with the exposure times. Sometimes the prints are too dark or light but it is never perfect with good contrast. How can I fine tune this process to achieve better results? I know this is an alternative process so maybe i cannot get good results? thanks for your time! oh and any good books or links would be great!

You're trying to to an interchrome. I think Kodak made a film for such a process, but I doubt if it's available anymore. You can have a print made then take a picture of it on slide film. It's one more generation of duping, but it's easier. For an enlarged positive, there's also Duratrans which is C print paper emulsion on a milky plastic base. But I don't know if Duratrans material is available either with inkjet technology so common.

thanks for your response. i am trying to enlarge my 35mm color negative film onto a transparent positive. i can produce an image but the problem is that the exposure and contrast of the positive image needs improvement. i am using a black and white enlarger with cc filters but perhaps it is better to use a color enlarger? i am looking for advice in this regard as i do not have much darkroom experience.
in terms of materials. i could make a positive 35mm print and enlarge that to ektachrome dupe film (8x10). i have this film. it is long expired but i will try it. thanks again!

What is the exposure time you are using?
For my experience exposures with less than one seconds with an enlarger are not really reliable (probably due some heat up time of the lamp). For times over one second you have to fight with the reciprocity failure of the film.
That’s the classical dilemma for enlarging on film…

much longer. when i use black paper on the easel it is +/- 45 seconds. without the black paper it is +/- 12 seconds. aperture is wide open at f/2.8

but it is never perfect with good contrast

Click to expand...

Check the usual suspects:
Stray light from doors/windows, etc
Don't use a safelight
Make sure the lens is clean and stopped down to f8
Check for stray light coming around the edges of the negative, projecting on the baseboard.
Check for stray light coming from the enlarger head, or around the negative carrier.

that is helpful, thanks. i will try that.

Start by going out and buying a real colorhead before you go insane. They're cheap enough these days. Does that film have an orange mask?
If so, there are some distinct tricks to getting past it. Can't elaborate here, but some of the old Kodak manuals listed the basics. Altering the
contrast up or down is something that will require serious silver masking skills - not a skill you're going to quickly acquire. Or you could pay thru the nose, have the things scanned and output on a film recorder onto tranny film. I applaud you on attempting this, but getting high quality results requires a distinct learning curve plus the appropriate equipment. You have to play the chords a long time before joining the symphony in this kind of situation. Even the pro labs of the past generally did it miserably, and as much as I hate mentioning it, it something better done these days digitally. Even acquiring an appropriate chrome film that isn't outdated is getting harder and harder.