Yes, I will do that next time.
But I read a post by a colleague in this topic that says that this developer is suitable for paper as well, and he said that in this case it must be diluted in a ratio of 1:15.
I sent some of this developer to a photographer in Tunisia and I was told that he succeeded in using it with printing.
Yes, I think you are absolutely right in your suggestion.It can also be used as a first developer in reversal processing if you add suitable amount of Thiocyanate to it.
I prefer to use the kit (ORWO) for reverse operations, as this is a disciplined and semi-standard process and gives expected results and does not require experiments or tests.
No, it works with all other types and categories of films in a very smooth and excellent manner,,Orwo's first developer and timings are meant primarily for use with Orwo UN54 film. For all other films, you do need to and must do testing.
Don't worry too much about the theory the manufacturer says.
Perhaps the literary expression betrayed me.In theory or in practice?
What chemical reaction is actually happening here? Would this be synthesizing p-aminophenol from metol and hydroquinone? Can anyone give more details?
I didn't see much description from him. Also the name to search is "gerald koch" as that is his user name here. Either way I might have to give this a try. It definitely looks simpler than paracetemol (rodinal synthesis from acetaminophen)There are some posts by Jerry Koch on the chemistry of Kalogen. Apparently, respective phenolates are formed which are less prone to oxidation and very soluble. Don't think PAP is ever formed.
I have a very crazy and possibly stupid idea in my mind.Jerry on Kalogen and phenolates.
"Paradoxically p-aminophenol, Metol and hydroquinone are more stable at a high pH where they exist as phenolates."
"Not only are there many recipes for Rodinal like developers there are several which use Metol and hydroquinone. Both these developing agents form phenolates with hydroxides just like paraminophenol."
"The concentrate contains the phenolates of both Metol and hydroquinone and in this respect is similar to Rodinal in concept."
"At a pH < 8 the phenolate cannot form as it must be around a pH of 12.
Chemically Metol and p-aminophenol are very similar. In fact Metol resists oxidation better than pap"
"Developers like Rodinal depend on the fact that the hydrogen on the hydroxyl group is weakly acidic. In the presence of a strong base the paraminophenol forms what is known as a phenolate.
R-OH + KOH ---> ROK + HoH.
Alkalies such as carbonates are just no alkaline enough. Should you use a carbonate what you get is an ordinary MQ developer such as D-72 and not Rodinal. The phenolates are particularly resistant to aerial oxidation hence the long life of such developer concentrates are Rodinal and Kalogen."
I have a very crazy and possibly stupid idea in my mind.
But it crosses my mind a lot.
...
Is there any proof of the image structure yielded by this developer formulation? Any sharpness, grain or speed comparisons? If not, then it is just a developer, and may be no better than using Dektol for your film.
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Sorry *, but the question must be asked and asked politely and with respect.
I do not suffer from delirium, my dear friend.This could be some help to you in your delirious state.
The idea is to replace the value of 12 grams (Metol) into three sections.
4 g Metol
4 grams p-aminophenol
4 g CD2
Thanks for the clarificationSuperadditivity of Metol with Hydroquinone is critical to Kalogen's success especially at the dilutions it is used for film. If you reduce the concentration of Metol or replace it with developing agents that are not superadditive with Hydroquinone, you'll get a relatively weak developer.
is my calculation erroneous?
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