Old Agfa Atomal / Orwo A49 / Calbe A49 questions

[James1]

A49 prevents building up too much density at some rather contrasty working films. I like it for aerial films like Rollei Retro 80 or Superpan 200.

Sounds excellent. And does the stock solution last for a reasonable length of time (in closed bottles)?

[Dali]

A49 prevents building up too much density at some rather contrasty working films. I like it for aerial films like Rollei Retro 80 or Superpan 200.

It might explain why I got very good results with medium speed films like Plus-X but no so good with Tri-X. It might also comes form my development time... I need to investigate further. BTW, I use the ADOX version which should be pretty similar the the Calbe version.

[Dali]

Sounds excellent. And does the stock solution last for a reasonable length of time (in closed bottles)?

I don't find the stock solution to last very long. 4 weeks, maybe 5... In fact, I store my exposed rolls until I get enough to use a full bottle of developer (1+1 dilution).

[piu58]

Sounds excellent. And does the stock solution last for a reasonable length of time (in closed bottles)?

I have used the stock solution over a period of 2...3 months without any degradation. For 1+1 dilution I filled small bottles which remained unopened until I use them. They last even longer, more than half a year.

[piu58]

BTW, I use the ADOX version which should be pretty similar the the Calbe version.

It is the same stuff.

[James1]

I have used the stock solution over a period of 2...3 months without any degradation. For 1+1 dilution I filled small bottles which remained unopened until I use them. They last even longer, more than half a year.

Thanks Uwe. That's actually pretty good I think. I have 2l packets for the most part, so glad to know I have a reasonable chance of using it up!

[Gerald C Koch]

When I suggested Metol as a substitute for Atomal I did so for a number of reasons. Among these are the fact that both chemicals are related in structure and belong to the same Kendall-Pelz group being based on aminophenol. Developing agents such as CD-1 are based on paraphenylene diamine and are in a different group. Their use proposes some different problems which Calbe may have solved with chemicals which do not appear in the MSDS. Another consideration was ease of access and price. The color developing agents may be hard to find and are usually more expensive. If Metol does not produce fine enough grain then Glycin is another possibility. It too is based on the aminophenol structure but is less active than Metol. It is also in the same KP group as Metol. By being less active it probably behaves more like Atomal. But again more expensive and harder to obtain for some in other parts of the world.

No matter what developing agent is substituted for Atomal, it is highly unlikely that the resulting developer will exhibit all the properties of the original Atomal developer.

[piu58]

> I have 2l packets for the most part

Here in Germany the 2 l packages contain 2 pieces 1 l packages. 1 l ist sufficient for 10 film which is quite a adequate amount.

In my younger day I used 600 ml packages for 6 films. 600 ml was the amount the most devleoper tanks need.

[AgX]

@Ian - interesting. I'm sure one of my reformulated packets of A49 stated one of the sachets contained CD1. That perhaps is the case for modern Calbe A49, but I don't have access to the MSDS to check.

@gorbas - thanks. Would love a copy of the whole book :-) so not practical - but as mentioned, if anyone reading this knows of one for sale, I would be interested!

Calbe offer some CD-standard developing agent as raw chemical, but not CD-1. That may mean, they don't use it in A49, don't make A49 any longer, or keep it for themselves.
Make your decision.

[Ian Grant]

CD-1 is in Calbe's A49 MSDS

Ian