micha
I’m currently using a combination of Efke 100 and Efke 25 with Calbe F09. But I have this nagging feeling that this combination isn’t exactly of fine grain, but just cheap. How does the dilution ratio affect the granularity? I’m using a 1:80 ratio.
I’d be grateful for any tips.
Micha
MirkoBoeddecker
Micha,
Who on earth told you that R09 is a ‘fine-grain’ developer??
It’s our coarsest-grain developer (along with Microphen).
But that’s clearly stated in the catalogue too :P
F09/R09 is the original Rodinal. A top-notch developer for plates and sheet films.
It produces a truly wonderful grey-scale modulation and you can also play around with the curve quite well.
Grain clustering, edge effects, visual sharpness enhancement – it does everything that fine-grain developers don’t.
If you’re not into that, go for A49. Dilution doesn’t really affect the graininess here. It’s more about the balancing ability.
By the way, I think the combination of efke 25 and F09 1+80 is brilliant. The film is fine-grained enough for my 30x40 prints and the grey tones in R09 are amazing.
Beautiful blacks in the eyes (grain clustering) – edge effect on the eyebrows – rich, brilliant prints.
But of course, it’s RELATIVELY coarser-grained than with A49 or other fine-grain developers. You just have to weigh up for yourself what’s more important to you and trade crispness for grain suppression.
With Fomapan 400, I only use the A49 because the grain in the F09 is just too coarse for me...
Well, I hope I’ve cleared everything up now.... :)
Regards
Mirko
uworischki
The f09 is certainly not a fine-grain developer, but it does produce more pronounced grey tones than the a49, particularly with Efke film (I have to agree with Mirko on that). As I mainly use roll film, grain isn’t really an issue for me.
Best regards, Uwe
micha
By the way, I think the combination of Efke 25 and F09 1+80 is brilliant. The film has enough fine grain for my 30x40 prints and the grey tones in the F09 are amazing.
I’m not saying the combination is bad, I just wanted to hear your opinion. I only use the combination for sheet films, though. One more question. What effect does the dilution have? Regards, Micha
MirkoBoeddecker
Micha,
The more you dilute it, the slower the film develops and the more balanced it is.
However, you must ensure that the active substance does not fall below 8–15 ml per film, otherwise the film may not be fully developed and may turn out flat.
R09 can be diluted to such a high dilution because it is very oxidation-resistant (unlimited shelf life).
Furthermore, there is a correlation between sensitivity utilisation and concentration.
In theory, higher dilutions should make it harder to push the film.
However, there are publications in specialist magazines from the 1970s claiming that at 1+400 and a development time of 2 days, the KB 25 is said to have reached 1600 ASA......
But that is just lab talk and has not been verified!
Regards
Mirko
Gast
R09 can be diluted to such a high degree because it is highly resistant to oxidation (unlimited shelf life).
… however, the long shelf life only applies to the undiluted concentrate. After dilution, Rodinal & Co. have a very short shelf life.
Alex
MirkoBoeddecker
Alex,
Of course. What I meant to say is that other developers, which aren’t as resistant to oxidation, would in theory become more balancing at higher dilutions, but because they’re less stable, they’d suffer an oxygen shock and give up the ghost.
The solution only lasts for a short time. The important thing is that it lasts for the duration of the development time.
Thanks for clarifying!
Mirko
Gast
Mirko,
Does this mean we should conclude that problems are likely to arise with high dilutions and very long development times?
As in the example mentioned—a 1:400 dilution and a two-day development time—hasn’t the solution long since become unusable?
What is the approximate upper limit for the solution’s shelf life?
Best regards, Jean-Michel
MirkoBoeddecker
Jean-Michel,
That’s exactly right.
Only a chemist can test whether, and if so when, the developer will run out during such an ‘experiment’.
It also depends on the subject (the amount of exposed silver), as depletion is caused equally by oxidation and silver reduction.
As long as you don’t go over 1+200, use at least 15 ml of active substance (concentrate) and don’t engage in development for longer than 1–2 hours (i.e. use the developer as we specify...), you have nothing to worry about.
The whole ‘2-day’ thing actually makes use of this effect. The film isn’t moved during those 2 days. What happens is this: the developer becomes depleted locally in the areas where it has reduced a lot of silver, and develops more actively in the areas where little light has fallen on the film, meaning it hasn’t had to work as hard there yet.
This means that, despite severe underexposure and overdevelopment, the contrast of the subject does not increase too much, because the highlights and shadows are developed to different degrees.
It is therefore entirely intentional that parts of the developer become inactive at certain points on the film surface.
Best regards,
Mirko
Gast
What is the approximate maximum shelf life of the mixture?
Hello there!
Here’s a recent update on this:
http://groups.google.com/groups?selm=buinu...ws.t-online.com
Alex
Jacques
Do you use Rodinal (R09) with Feinkönig film? Give this a go:
Rodinal 1+50 + 4g sodium ascorbate (vitamin C) per litre.
I’m not joking – it really works...
Efke 100: 10 minutes
Bye,
Jacques
cfb_de
Hello Jacques,
What exactly do you mean? Sodium ascorbate or vitamin C? Vitamin C is free ascorbic acid, not its sodium salt.
Best regards,
Franz
Jacques
Hi Franz,
Sodium ascorbate.
I just mentioned vitamin C for those who have no idea what NA might be.
I should have been clearer – sorry.
Vitamin C is ascorbic acid.
Sodium ascorbate is roughly ascorbic acid plus bicarbonate of soda, if I remember correctly.
Regards,
Jacques
