Gast
Is this developer the same as Rodinoll?
If not, what's the difference?
Niall
MKL
Hi Niall,
Calbe A49 is completely different from Agfa Rodinal. A49 is a fine-grain powder developer. Rodinal is a liquid, highly concentrated acutance developer.
To put it simply, A49 produces finer grain and lower acutance (sharpness).
Rodinal will produce noticeable grain with high-speed films and high acutance. Rodinal concentrate will keep almost indefinitely in airtight containers, whilst A49 stock solution will keep for about 6–12 months.
Calbe R09 is similar to Rodinal; it is based on the old formula and is less concentrated.
Hope this helps.
Best regards,
Michael
Gast
In addition to Michael’s comments, I would like to add that Calbe A49 is also excellent for pushing films (unlike Rodinal, which reduces the film’s speed); I really like it for portraits, or for pushing TMax 3200 up to EI 3200 (the actual speed is around 1000 to 1250) – works well with A49 1+1, 20 mins.
If diluted, A49 is still not as sharp as Rodinal (which I prefer for landscapes or architecture, though I recently switched to a home-brewed recipe by Barry Thornton, which gives higher film speed and less grain).
Also, if used at 1+2 or higher dilutions, you won’t achieve very high negative contrast levels even with longer development times; for me, 1+1 is the ideal compromise; I don’t know which film you generally use, but I love Fuji Neopan 400 (shot at 320) in A49 1+1, 13 mins, for portraits (and Neopan 400 at EI 250 in Rodinal 1+50, 9 mins, for landscapes).
Roman
Gast
I'm using Neopan 400 at the moment. I'm giving it a go, so to speak, and I
develop it using the standard Rodal dilution!
It gives good results, but I'd like to try A49!!
Now tell me, why do you push or pull a film??
And what effect does it have on the prints??
Niall
Gast
...Come to think of it, why do you lot change the film speed!!
Niall
Gast
Pushing the film: not ideal for image quality; you’ll end up with more grain, extreme contrast, and you might get blown-out highlights or washed-out shadows, or both at the same time… Why do we do it anyway? Well, sometimes there simply isn’t enough light to expose the film at its true speed, and sometimes a tripod and long exposure times aren’t the answer (e.g. when photographing people – movement would be visible).
Pushing is mainly used for taking pictures of people in low light, when the subject is more important than the picture quality...
Pulling film: This is used to reduce negative contrast in scenes with very high contrast lighting (e.g. bright sun at midday).
Lowering the exposure index of your film (i.e. shooting 400 ASA film at EI 250) is not always pulling film – most manufacturers are simply a bit over-enthusiastic when it comes to rating their films’ speeds...
Shooting at the ‘real’ film speed (which, depending on the entire process of taking a photograph – camera shutter, light meter, development – varies as different developers yield different film speeds with the same film type, the type of light source in the enlarger, the contrast range of the printing paper, and the print developer used) will give you negatives that are easier to print, with more open shadows that reveal finer detail.
There are methods to establish the ‘real’ film speed using a densitometer and a lot of maths, or you could use one of the following two methods:
go to <htttp://www.barrythornton.com> and click ‘Unzone’;
or go here:
<http://www.halfhill.com/speed1.html> and
<http://www.halfhill.com/speed2.html>
.. or you can simply rate your film slightly lower than the speed printed on the box (64 to 80 for a 100 film, 250 to 320 for 400), and reduce your development times by about 15%.
Gast
Dear Niall,
A49 is a developer similar to Agfa Atomal; it produces a very fine grain and is also a good choice for high-speed films rated at 27 DIN and above.
However, you do need to expose and develop with a little more precision; I only use A49 for films with higher speeds.
If you’re looking for a developer that falls between Rodinal and A49, I’d recommend ILFORD ID 11 – that’s the developer I use for films between 15 and 21 DIN.
Also, do not use the undiluted developer, as the processing times are not specified very precisely, which can lead to inconsistent results across different films.
It is better to use a dilution of 1+1 or 1+2.
Finally, I would not push or pull films, as they deliver the best results at the speed printed on the package (although there are some developers that alter the speed by approximately ±3 DIN for optimal results).
Werner
MKL
Niall,
Why do we push and pull film? Well, first of all, the ISO ratings don’t have to be precise for your equipment and personal preference. That’s why many people do calibrate their processes to achieve the desired result. Besides that, you usually push film when the scene has low contrast. By pushing, you extend the density range on the negative for a given exposure. Let’s say the scene’s contrast is 3 EV steps; you then increase the ISO setting (underexpose) and extend the development time so that the negative density range becomes 1.2 (Dmax – Dmin), which equals 4 EV steps. Pulling would be exactly the opposite.
Pushing causes grain, whilst pulling is a very common way of adjusting to standard requirements whilst still ensuring safety in bright scenes. It is usually better to develop for a shorter time and print harder rather than doing the opposite.
br
Michael
