Super-XX Pan equivalent

[David Nash]

I'm afraid it's a continuation of the colour separation question!

I've been reading a wee bit more on the subject, and I've found that in the good ol' days, the 'best' film for making colour separation negs was Kodak Super-XX Pan 4142 (developed in HC-110 solution B). I think this was because of its 'even sensitivity' that produced a 'straight-line characteristic curve'. I'm assuming that this film, and Kodak Separation Negative Film 4131 (another recommended film) are no longer available - I haven't even checked the Kodak website, so I may be pleasantly surprised, but I'm not holding my breath!

I just wondered if you could recommend a currently-available film with similar characteristics. I know there are some European films that are supposed to be like the older thick films, but I've no idea about their suitability for this application.

When I last attempted this process, I just used Tri-X in Pyro (what I normally use for platinum printing), but I suspect part of my problems were due to the tanning, and the contrast was probably too high.

David

[John Berry ( Roadkill )]

Super-XX has been gone so long that nobody even stops by its gravesite anymore to drop off flowers

[sanking]

What is your application? If you are doing in-camera separations for a process like gum bichromate virtually any modern panchormatic film can be made to work reasonably well.

The major requirments for a film for color separations are, 1) linear straight line, and 2) equal to close same response with RGB filters. However, even Super-XX did not satsify both of these requirements completely. Super-XX had a long straight line but strong adjustment for blue light, both in exposure and contrast, was necessary.

Looking at the curves and spectral response of all current films my recommendation would be TMAX-100. I am very confident that with a minimum of testing I would be able to make this film work every bit as well as the old, and much lamented, Super-XX.

[Jim Rice]

*puts some flowers on it's grave*

[J. P. Mose]

Here may be your answer: www.jandcphotography.com

J and C advertise their "Classic" films (ISO 100, 200 and 400) being similar to Super XX.

There have been several postings on this forum and photo.net about the use and development of this film.

[David Nash]

HI Sandy

Thanks for that. I'd like to pick your brains a wee bit! I'd like to know how you would go about testing a film for making in-camera separations. Also, what should I be looking for when looking at spectral sensitivity and density curves. I do have a densitometer that I got a while back, and which I've never used. I probably don't need an in-depth step-by-step response, but a list of the procedures you follow would be really useful.

Thanks

David

[Terence de Giere]

If you find a good equivalent for Super-XX film, you can also use the Kodak DK-50 formula for development as it gives a good straight line response as does HC-110. Any film that can produce a long straight line portion of the characteristic curve could be used as long as it is panchromatic film. Super-XX was pretty grainy, compared to modern emulsions, so sheet film sizes give cleaner images.

How do you intend to composite the images? Scanning and digital? When processes like dye transfer were still available, color correction masking using Pan Masking film made for much better, more accurate color with direct separations. These masks were made from the developed direct separations, and sandwiched with the separation negatives during printing. The masks compensated approximately for color reproduction faults in the print dyes. Pan Masking film is not made any more however.

Today's inkjet printers normally supply similar color correction digitally behind the scenes, if your images are to be composited from scans of the negatives. With analog or digital color correction masking, direct separations should produce more accurate color than color negative or color transparency film reproduced via the same process.

The use of a densitometer is very useful when testing for correct exposure and development times, as each separation negative - red, green, and blue, require different times to match the curves.

If you are using sheet film, it is best to use the same holder, and the same side of that holder for each negative to assure best registration, which means you need a darkroom nearby to load film between exposures. That is because manufacturing tolerances of holders are not designed for registration across holders. Different holders may result in more mis-registration of images. If you are using roll film, you could compensate for contrast differences between the red, green, and blue images after scanning the images using an image editor. 120/220 roll films might buckle a bit causing mis-registration, depending on the camera. 35mm film should be flatter in the camera than 120 sizes.

If you can make multiple exposures on the same frame in a roll film camera, you can also experiment with color separation filters on color film. Depending on the bandwidth of the filters, the resulting color reproduction of the color film can be strikingly different from its normal rendition, even if grays are reproduced correctly. The color reproduction of a system depends upon the bandwidth of the filters, the film's spectral sensitivity, and any subsequent steps and diodes, phosphors, dyes, or pigments used to reproduce the image.

[Terence de Giere]

If you want to see and download a collection of color separation images, the Library of Congress has available photographs made in Russia from about 1900 to 1915 by a photographer using a direct color separation camera (it had a moveable plate allowing three images to be made in rapid succession). You can search the collection of scanned images and practice assembling color images etc. When properly corrected some of these images are stunning, even by today's standards, 100 years later.

http://www.loc.gov/exhibits/empire/