"Roba Apposta": reversal process for film and paper

Hi everybody,
I just completed the profiling of a couple of widely available papers (Ilford MG RC and FB) used in-camera and then inverted using “Roba Apposta” by Branco Ottico, an Italian company. “Roba Apposta” is a reversal development process sold as a kit that works for both film and paper. I used it only with paper.

I wrote a paper on this profiling. Here is the link:
https://www.marcoannaratone.photography/Tests-(PDFs)/thumbs

I included below an example from a project I just started (“Syringes”). It’s a 14x17in cut from 16x20 and used inside my Lotus ULF camera. G-Claron 355mm @ f/45.5

I have no relationship with Branco Ottico so I suggest you have a look at their site if interested:

http://www.brancoottico.fineartlabo.com

Cheers!

Marco thank you for the in-depth write up
I also enjoyed your other writing/musings
very thoughtful and left me thinking!!
Peter

Peter Schrager said:

Marco thank you for the in-depth write up
I also enjoyed your other writing/musings
very thoughtful and left me thinking!!
Peter

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Hi Peter,

thank you for the kind words! Many years ago (too many...) a lot of people invested their time in forums like this one to bring me up to speed re: large format photography. When I have something to share I think it is a bit my obligation now to return the favor.

Cheers!

Very nice and detailed writeup! I had a great time last year in the midst of covid crisis making in-camera reversal prints. Some of my exposures at EI 3 were long running into several minutes and reciprocity was a major concern. Did you do any testing with exposures that ran into reciprocity failure? Are there correction factors that you found from your testing that you can share?

My longest exposure was two minutes and I did not have to introduce any correction to account for reciprocity failure. But I believe this applies to the specific papers I use (someone should correct me if I am wrong), i.e., Ilford MG RC and FB. Another paper may exhibit reciprocity failures much sooner (or later).