Black &White reversal processinggreenspun.com : LUSENET : Large format photography : One Thread
I would like to hear about experiences, tips, and suggestions for processing black and white films as transparencies. I've worked with T Max and Delta 100 and Pan F using the Kodak T Max reversal kit but would like to work with faster films (good source for HP 5 Plus motion picture film?). Thanks for your help...
-- David Carney (firstname.lastname@example.org), July 04, 2000
Wht not try Tmax 400. Or if you are serious about HP5 then expose a few short rolls of the same subject, bracketing by upto, say 2 stops either side, then develop each for different lengths of time (always remembering to record each and every little thing that you do to achieve the shot to get a viable working formula). Also it may be a good idea to get a quantity of potassium ferricyanide if the slides are consistently too dark.
-- David Kirk (David_J_Kirk@hotmail.com), July 04, 2000.
Tri-X is faster than HP5+ or TMAX, and IMO is better than either one. Pat
-- pat krentz (email@example.com), July 04, 2000.
David, I have done a considerable amount of black and white reversal processing. In fact the majority of the film I shoot now is reverse processed. My criteria for what I consider a good slide, and therefore a good slide film, are necessarily going to be different than yours, but I will give you what I can. First off, I am after two things in my transparencies: tonality and fine grain, both of which go hand in hand. Shooting speed is secondary to me as I amost uniformly use a tripod. My film of choice for reversal processing is Technical Pan. Tech Pan is a tough film to work with normally and reverse processing it is no exception to that. But the fine grain characteristics and tonal qualities of the film more than make up for the slow speed (I shoot at EI 12 for reversal) and the tight controls needed for processing. Others will tell you that TechPan is too contrasty to use as a slide film, and if processed by the Kodak kit or by any of a number of protocols for other films this is true. However it can be processed to contrast levels that make it applicable for pictoral work. I get about eight or so stops of usable exposure contrast which matches the typical range in an "average scene. Aside from TechPan I have also reverse processed other films such as HIE, and am currently working with MACO's PO-100 orthochromatic film and soon their ORT-25 ortho film. I worked with T-grain films for a while, but never got results that I liked. The final slides had a "muddy" appearance that I ascribed to the tabular grain structure. I never went back to see if I could work out better second developers to eliminate that problem as I have other films that give me what I need.
Anyway, in a more general theme, any black and white negative film can be reverse processed. Using comercial kits or blindly following a published protocol may give you passable slides, but to get optimal results you must match the development to the particular film you wish to use. Personally I go through an exercise of manipulating the first developer to get the contrast that I want, and let the speed fall where it may. Alternatively one can manipulate the first developer to get the speed needed and just live with the contrast that results. I start off making a series of exposures of a step tablet and develop them while varying the first developer componants as well as the time in the first developer, manipulating those variables as fits the results I am getting until I am happy. Then I go shoot a number of real world scenes bracketting at 1/3 or 1/2 stops to make sure that the speed is truely what I calculated from the step tablet exposres and that the contrast range of the film is appropriate for the use to which I will put the film.A note on processing. Since the transparency is the final product and you cant make up for deficiencies through printing, your processing controls must be spot on. Think of the time and temperature requirements for doing E6 processing at home. These same requirements exist for reversal processing black and white films if one wants to get consistant and reliable results. I personally hold my temperatures within 1/2 degree while processing. I also time my steps very accurately. The most important step is the first developer as it is where the image contrast and density is determined. Being anal retentive in your processing is a good thing. That said, it is not outside the ability of any reasonable careful worker to produce good tranparencies. Anyway, after that bit of rambling, I will go. Let me know if you would like more specific information concerning the specific steps in reversal processing.
-- Fritz M. Brown (firstname.lastname@example.org), July 05, 2000.