Many developers are just takeoffs of some Kodak developers such as D76, Dektol, HC110 and etc.. The same is true of fixers. The reason is that there are only a few such "good" formulas out there. Kodak was working on a whole family of these new B&W products when I retired. IDK if Kodak is still using D76 for release testing.
PE
I don't consider Crawley to be a truly credible source. I'm thinking more of James, Haist etc. I can't find any reference to 75g/l being somehow "optimal" for a solvent developer. And of course what is optimal also depends on the emulsion.
And many Kodak developers are also derived from other manufacturers formulae, in Kodak's case they evolved a number of developers from the Wellington & Ward Fine Grain Borax MQ developer including D76. Other Kodak developers acme from companies they acquired.
Ian
#6 - the availability of constituent components - is really not relevant to developers like D-76/ID-11, X-Tol, Rodinal, D-72/Dektol and probably a bunch more.
The constituent components of these are really common chemicals which are used outside of photography, and aren't subject to special safety or security concerns.
Whether or not they are conveniently obtained by individuals (especially in Canada) is a different question - most of the sources are really only set up to deal with businesses.
True, but such experiments should have been done somewhere around 1920s, otherwise we are forced to conclude that D-76 contains an arbitrarily chosen amount.There is nothing difficult in measuring the solubility of the silver halides in various strength sulfite solutions. Any second year chemistry major could do it.
This is an interesting note . HC110 contains catechol, a chemical that is considered toxic, but which is also produced in huge amounts to be used elsewhere in chemical synthesis, so there is absolutely no danger that it is no longer available. HC110 also contains HQ, which is used in cosmetics. Other constituents of it, indeed, are out of reach.Rodinal, and any Pyro developer come to mind as being problematical due to toxicity, and HC110 is totally out of reach of the home darkroom worker.
PE
As PE mentioned making your own HC-110 is problematic. Some of the chemicals are not commercially available and even Kodak was forced to synthesis them. In addition very toxic gases (is hydrogen bromide and sulfur dioxide) and special equipment are required. Certainly not something an APUGer can do in their garage.
While some of the older formulations do not work well with modern emulsions SOME work very well like D-76 and D-23 as two examples. So be of good cheer.
True, but such experiments should have been done somewhere around 1920s, otherwise we are forced to conclude that D-76 contains an arbitrarily chosen amount.
Some of these might have it: https://pubchem.ncbi.nlm.nih.gov/compound/Metol#section=Chemical-VendorsReally? What about metol? Where can you get it for a business?
aka Germain's Finegrain Developer? Yes, this person had a sense of humor. I have long suspected that the use of sulfite parallels the story of sugar vs fat, and the sulfite industry similarly bribed someone influential, and ever since that point in time 100 g/L sulfite became the "principle" of fine-grain development.This is somewhat common to arbitrarily pick a arbitrary weight. For D-76 it is 100 g for Perceptol 125 g which is close to the amount of sulfite that can remain in solution below 65F. Then there is the famous 777 developer.
Thank you, I am aware of this database, but one can spend a long time finding the link that is usable. Certainly not Sigma, too expensive. But you are right in that if Sigma carries it, it must have been used recently somewhere else than photochemistry.Some of these might have it: https://pubchem.ncbi.nlm.nih.gov/compound/Metol#section=Chemical-Vendors
PE, obviously this part of your prospective book would be highly informative for those interested in truly up-to-date info. Also, it occurred to me that one may hesitate to write a monograph, but a book with chapters written by different experts may be a more feasible, and perhaps even a better idea.Well, in answer to the above comments, I write books about emulsion making not processing! Volume #1 is now out of print except for the commitments I have right now. I am working in volume #2. As long as supplies last, the Formulary in the US and Fotoimpex in the EU both sell the first volume.
I have said many times that EVERY book on photography and specifically emulsion making or which refer to emulsions is incorrect or has errors. Many are duet to redaction by the authors employer!
Crawley did do some good work, but the work on Iodide developers with enhanced edge effects is obsolete, but this brings up the question of how many other formulas are suspect.
PE
This is quite true, however I could not name them as they have pretty much vanished from the market. The ones I named are enduring and probably will endure.
PE
Rodinal, and any Pyro developer come to mind as being problematical due to toxicity, and HC110 is totally out of reach of the home darkroom worker.
It is certainly not saturated!Basically, the market is reducing to the few best!
As I read through this thread, I cannot help but think of a bit of Tom Waits that I heard a wonderful performance of last weekend.
Here is one of Tom Waits' performances:
Since Grant Haist published his two volumes on photography there has been little R&D done. My question is therefore what groups are you thinking about other than the much older ones in Jacobson, Crawley and Anchell? There is of course the newer T-grain or Delta not discussed by Haist ones but I am unaware of any others that could be assigned to a new group.
As far as D-76 is concerned it is considered a universal developer. On what basis do you consider this not to be true. I would not base any decision on what commercial labs produce as their work is usually pretty slipshod.
XTOL was essentially the first (and last) developer to "beat" the D-76-type when it comes to the overall balance of granularity/sharpness/speed, and the improvement is very slight.
However, from a simple encounter with Rollei Retro 80S, one can conclude that there are classes of films that may develop similarly only within a class. So, which current films are "retro" and which are not?
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