December 12, 2014

arabica coffee or not

We recently had a discussion at Apug if pure arabica coffee without Vit-C would do any development, one guy reported that he had no development at all with arabica coffee. We can read at different places that the cheap and awful robusta would be the best for developing film and arabica would be worse, but no development at all? Furthermore, I didn't have single report here on my blog of any failure caused by arabica coffee. Au contraire, people told me that they used 100% arabica "premium" instant coffee, because it was at hand, and got excellent results. I also made such an experiment and could confirm, that pure arabica coffee was not worse than any other I tried so far. But I made the test with Caffenol-C. Now I decided to make a side by side comparison of 100 % arabica and the cheapest instant coffee available here without Vit-C, to get the results from coffee with washing soda alone. To make it worse, I used decaffeinated(!) arabica. Both samples were developed at the same time side by side. To make a simple story simple: I can't distinguish both! They look exactly the same, even held against a lamp for better judgement: identical blackening. To be honest, I wasn't surprised very much. But of course using a more expensive coffee is a waiste of money.

PS: my old flickr buddy Larry aka inetjoker just said that he only once had a failure with caffenol, and it was a deacidified coffee. Again no big surprise, caffeic acid is regarded as the main developing agent of coffee. Thank you so much, Larry for all your help and simply for being around always.


Both developments were made with snippets of Polylan F, I cut off 1 edge for the arabica developement and 2 edges for the "cheap" development for further reference. The recipe for both was:

40 g/l instant coffee and 40 g/l washing soda waterfree, that's it. pH was about 9.9 for both. Fixing and rinsing as usual.

Stand developed 60 minutes at room temp with some stirring every 10 minutes or so. That was a quick and dirty test, everybody can repeat it with a minimum effort.

See you guys, happy developings


December 7, 2014

the new old RPX 400

 Hi coffee users and abusers,

good news about film and Caffenol. The "original" Rollei RPX 400 is back!

The RPX 400 from the very first production was a great film with good pushing behaviour and nice grain. Then the emulsion was changed obviously without any announcement. I couldn't see any difference to the Kentmere 400 now, and I never liked this film. 
Here is my original post on the RPX 400 with an update adressing that point:

Many people, incuding me, complained about this inaceptable behaviour. After the new package design was launched recently the emulsion obviously changed again, now showing again all the great features of the first batch. Obviously our lament was successful. Shadow detail is splendid, even with extremely contrasty subjects. EI 1600 is possible. The RPX 400 needs a powerful development to show his best side.

I used exactly the same development as before: 5 minutes presoak, Caffenol-C-L with 1.2 g/l pot. bromide, 80 minutes at 24 °C stand development with constant agitation only for the first minute. And I got the same great results as almost 4 years earlier. EI was 800, all shots done with a Dynax 5 (Maxxum 5) in multi-segment metering mode with aperture priority at f/4, no manual exposure compensation. The subject contrast was big to huge up to more than 10 stops! Only very small adjustments were made in postproduction. Shadow detail was so splendid that I had to darken them a bit.

Credits go to a friendly guy who sent me 2 films for this test. Thank you very much! And thanks to the 2 charming girls who let me take the picture.

Best - Reinhold