For some odd reason, you made me think of the person who, upon being exposed to a treatise by Thomas Acquinas on "The Divine Simplicity" said "If that's His simplicity, I can't imagine what His complexity would be like."
It wasn't the difficulty of the process that stimulated my wit, it was the fact that it seemed that you expected every APUGer to have the chemicals and to be able and willing to go through that for a Rodinal fix which might or might not be better than store-bought. Seemed more complex than it is, and I'd have to wait a week for delivery of the test gear.I agree with the comment on Acquinas, but how hard is a titration? After learning to use the balance, titration is usually the first thing they teach you in chemistry class.
You could probably use USP ascorbic acid to titrate against if you really wanted to give it a try...
Ian;
I think HC-110 is rather good as a developer and has good shelf life. I think that some of the higher dilutions of HC-110 have not been fully exploited and may prove to approach Rodinal. I also believe that a Metol based Rodinal, if stable, would be superior to Rodinal.
PE
I took your suggestion. I made some KOH using the K2CO3 and CA(OH)2. A 0.1 normal solution of ascorbic acid added slowly to a sample diluted 10:1 gave a pretty sharply defined transition form basic to acidic on my pH meter. I estimated closely enough for government work that the KOH I made was about 1.25 N.You can use your pH meter too if you like. Just titrate to pH 7. I was trying to keep it simple by mentioning an indicator. But nowadays, most tinkerers will have a pH meter.
Some years ago, I used HC-110 a lot, even for developing paper. For film, I usually added a modicum of ascorbate. For paper, I added some carbonate and some sulfite, IIRC. It was always reliable and quick to prepair, which was a virtue at the time. I was working for NASA, principal oboist for both Peninsule and Norfolk Symphonies, and photographing guest artists at dress rehearsals, providing them with prints the next day. Did I mention having six kids?
I have a portion of a bottle a couple of years old, looks and works like new.
That's when my wife and I worked on making the kids. It was a lot of fun, too.And what on earth did you do with all your spare time??
Bob H
Actually, you don't even need to make the ascorbic (or KHP) to a particular normality. You can simply weigh a known amount into a beaker and add enough water to get the solution high enough for your pH electrode (or add your indicator), and then start titrating.
Now I read this book,the google quote gives the wrong impression.It is in fact phenidone which the book says is sensitive to hydrolysis in alkaline media.Metol is said to be sensitive to hydrolysis in alkaline media:
http://books.google.co.uk/books?q=metol+hydrolysis+karlheinz+keller&btnG=Search+Books
If 198g/L (1 molecular weight) sodium ascorbate is added to Metolal concentrate (M+A),the film speed is increased.For TMX EI: D-76=64,PC-TEA=80,M+A~160.The grain is reduced but could probably be restored to Rodinal like levels by making the concentrate more alkaline.Dev time M+A=2x that for Xtol 1+1.
www.ccohs.ca/oshanswers/chemicals/chem_profiles/sodium_hydroxide/
Oh.Reviewing my notes,I did not put any sulfite in, so it was done without sulfite.
Metolal derivative,call it MA-1:
Water 150ml
Metol 8g-if the solution is heated, be sure to cool to room temp before adding the next ingredient, the hydroxide.
Sodium Hydroxide 15.6g
Ascorbic acid 35.2g
Water to 200ml
For use dilute 1:50, develop for about 2x the Xtol 1+1 time.
There are notes on sodium hydroxide safe use earlier in this thread.It attacks people and parts thereof.
www.ccohs.ca/oshanswers/chemicals/chem_profiles/sodium_hydroxide/
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