To be curious for new substances is helpful, I get interesting once in the thema coffee developer, when I read in internet the using for high resolution films and that they will get some fog. But coffee has more than 800? ingredients and - I am a green tea drinker.
So I have only an eye on these things. An interest is for commercial available substances of qualified purity, which produce some fog and do not ruin speed like Thiurea. Since starting gelatine-AgHal research 1880 all interest was in mixed emulsion and not in monodisperse emulsion. With monodisperse high resolution emulsion you get a more scientific answer, when you test developing substances. The grain distribution of mix-emulsion will "smear" your result. But all old literature and the bibles of photochemistry are all based on these old tests.
This "smearing" will happen in all tests, when you work with normal films with a high grain size distribution, and you have a lot of difficulties to detect the real problems in photochemistry like speed, faults, equalness. Thanks my new film GTP, which is now on the market, I could enhance my chemistry, because the grain size distribution was more little than ever and the normal gamma for normal developers higher than ever. Thanks this I could detect mistakes of the past better and cancel them in the HDR chemistry. In my new datasheet I describe, that the old problem, to get absolutely faultless developed areas since 1880 (Richard J. Henry wrote a thick book on that - Controls in black and white photography, sec. ed. 1986), has to do -perhaps- with following:
In my eyes the spooled film - in a cartridge - and in a developer spool - will act like a kondensator in electrotechnics. The film can accumulat em-energy. In the moment the kondensator comes to an electrochemic bath (the developer is) several things in the moment of starting development will happen and - when the field is strong - disturb an equal quality. I do not mention the silverscum in dirty tubes, this is another, near equal problem of galvanochemistry. The simpelst in this thinking of mine is the short circuit via the perforation holes (cavityresonator?) up and down on the film.
When the "balance" of a developer is quite perfect (and you can use it, as an example, for correct halftone G=0.5 with Dmax for monodisperse 20°C 1+5 5 min and all mixemulsion like normal 100 ISO films with 400 ISO undiluted 12 min as with the HDR), in the moment of contact with film the final result is "programmed". In other words - normally you need not more to move the developertube, only developer fill in and wait. I test this from a theoretical point of view and for all standard motives it works good, for studio-photography (with their flashlights - em-impuls!!?) with white background it would better to move the tube in the first 30 seconds, then you can "smear" the white to a equal white. Testing full exposed films (only full white exposures) in full length you see -without moving- now some weak marks on the corners or sometimes weak clouds. In the beginning of a spiral the curvature is stronger (tension in gelatine) as at the end of the spiral - this will influence also the result. Spooling this developed film back in the spiral and when you have marked the areas, sometimes you can see something: When you see the spiral like a coordinate cross, in one area (lets say northpole) all these signs will get together a sign like you will have seen once in physics.
Once a scientific client from me has storaged his films in a refrigidair, on this stands an old microwave. Often he got flashes when he wants to open the refrigidaire. He got sometimes flashmarks in his films using in vacuum, I need together 5 hours telefon calls to detect this. Together with the normal known flashmarks I saw never described phenomena on these films. Thanks this solved problem I am open for new ideas for enhancing classic chemistry. Normally all professional users will make a prewatering for their b/w E6 or C41-films, perhaps in future this can be better. And it has to do with the holy grail of all secrets of emulsion making - the wetting substances. The first wetting substance in history of production was a natural product, it was in use until 1960. To look for some new "old" substances can be interesting. Old substances are more oecologically.
