I have not used Copex Rapid, but I highly doubt the 14 stop claim. Same for CMS20 etc.
Data please. Not lines/mm. H&D curves are required. I have still never seen an example that did not show abrupt losses of contrast in highlights and shadows.
OK, Gerald, but, essentially, your formulae are similar to standard MQ developers, with the exception of the addition of Phenidone (I don't think that that addition really matters with tone, as phenidone apes metol).
So I have tried straight metol and then diluted MQ developers and have gotten the same results. With ImageLink HQ it's really not possible to 'get it all in' with contrasty scenes because the highlights and mid-tones meld into one when sufficient exposure is given in order to render shadows properly. For low contrast scenes the film is sensational. - David Lyga
NOTE: one interesting thing with this film: If you expose for FULL shadow detail and you develop for an EXTREMELY truncated period (maybe 1/8th the time), you will 'get it all in' but your negative will be so thin (because of the greatly inadequate development time) that you cannot make a decent print.
The data was published several times by Henning Serger here on APUG and on aphog.de as well.
You might do a search here, just recently in his Photokina 2012 report Henning repeated what was already know about Copex Rapid.
At Carl Zeiss AG, Oberkochen lenses are tested with those super films.
Zeiss published their data in several Camera Lens Newsletters during the last decade.
Hi Georg16nik - I remember seeing Henning Serger's recent report but if I remember correctly these were resolution tests, not characteristic curves.
Gerald, David, when I experimented with XR-1B I found the curve I got with Tech Pan was similar to Technidol. I have not tested Copex Rapid.
I've had good results with ortho litho sheet film and a simple metol/sodium sulfite developer:
1 liter water
a pinch of sulfite
0.5 grams metol
8 grams sodium sulfite.
I expose the film at roughly EI 0.5, or 2 seconds at f16 under sunny conditions and develop 4 to 6 minutes continuous agitation in an oversize tray. Tonal range is not as good as a standard film like Tri-X, but contrast is near normal. Tonality, for lack of a better term, is not quite like standard film. Uneven development is sometimes a problem, but usually not too bad.
Happiness is a load of bulk chemicals, a handful of recipes, a brick of film and a box of paper. - desertrat
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David, Phenidone does not just mimic the properties of Metol but has some unique properties of its own. Its use in the two Perfection formulas is to increase film speed and latitude. For example, the POTA formula (which uses only Phenidone as the developing agent) was developed by Marilyn Levy for the Photo Optics Technical Area (POTA) division of the U.S. Arms Electronics Command to be used to record atomic testing which needed a film/developer combination capable of recording a very large contrast range. This formula will give an 18 stop tonal range with most panchromatic emulsions. Ordinary film/developer combinations can only handle a range of 5 stops.
With high contrast films, such as Kodak Technical Pan film and document copy films, this developer produces a negative which preserves the normal pictorial contrast while retaining the film's extremely fine grain.
A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.
~Antoine de Saint-Exupery
To throw another developer into the fray:
Soemarko LC-1 "improved":
750ml distilled water at 125F
4 g Metol
80 g Sodium sulfite
4 g Hydroquinone
20 g Sodium bisulfite
Distilled water to make 1l
For use, dilute 1:5 to 1:10...5 to 10 minutes at 75F
I've used it with Arista lith sheet film and it sorta-mostly works. Sorta-mostly is as good as I have ever gotten these microfilm/lith wunderkind developers to work.
Sometimes, using special developers, depending on the film. The results are usually still pretty contrasty, but they are usable and are very good for some subjects. (These films usually have a more uniform grain size and are built especially for very high contrast. A low contrast developer will get what it can out of them, but the film just isn't made to respond with even gradation to a wide range of light values.) The special developers are low contrast types, often called document film developers. Some examples are shown above. Most microfilms and some litho films work reasonably well with these, but you will have to experiment to find out and to get the right exposure and development combination. A couple more developer examples:
Sodium sulfite 25 g
Phenidone 1.4 g
Borax (decahydrate) 2 g
Benzotriazole 0.2% 15 ml
Substitute sodium metaborate for borax to get higher speed and contrast.
Benzotriazole may not be active at low pH and could be eliminated. Potassium
bromide or iodide might also be substituted.
LC-1B low contrast developer:
Distilled water (125F) 750 ml
Metol 4 g
Sodium sulfite 80 g
Hydroquinone 4 g
Sodium bisulfite 20 g
Distilled water to make 1 l
This variation was designed for Arista APH film for both interpositives and negatives. It is similar to LC-1 diluted 2:3:5, but with more sulfite and bisulfite. Dilute between 1:5 and 1:10. Develop 5 to 10 minutes at 75F.
Ref: Siegel, J, “Post-Factory Photography Journal”
James, C, “The Book of Alternative Photographic Processes”
Thanks Gerald for the info on Phenidone, but we all have to admit that there is a mighty difference between Tech Pan and ImageLink. Tech Pan 'gets it all in' and the other does NOT. With Tech Pan all you have to be careful with is development. Most of the other formulae presented are really standard MQ types having both metal and HQ.
I do not (obviously) have the definitive answer here and maybe that definitive answer is in the negitive. I have YET to see this ImageLink presented 'getting everyting in' for a contrasty scene . - David Lyga
Another low contrast developer candidate is C-41 color developer.
Cheap enough to buy, no need to make your own. Formula is:
Water 800 ml
Potassium carbonate 38 g
Sodium sulfite 4.7 g
Potassium bromide 1.5 g
Kodak anti-cal (optional) 1 g
Hydroxylamine sulfate 3.9 g
CD4 5.9 g
Potassium iodide 1 mg
Acetic Acid to pH 10.00
Water to make 1 liter
Well, at least it's not YAMQ.
Source: Francis A. Mitner, rec.photo.film+labs, 2002; attributed to Photo Techniques magazine