Pyrocat-HD, Besseler tube, and Efke 25

[k_jupiter]

Hi, title says it all...

I have 5x7 Efke 25 shot at 25, a Color Besseler tube (8x10 split for 5x7 use) with motor unit, and Pyrocat-HD for a developer. Any advice for times, dilution, quantity of developer, and/or things to look out for?

I also have my standard W2D2+, Rodinal, and 777 developers. I would suspect the Pyrocat is the best to start out with for this developing setup.

And no, the images are not important. They are of a house designed by Maybeck, a block from my humble abode. It isn't going anywhere anytime soon if I screw this up.

tim in san jose

 

[noseoil]

tim, I don't expose Efke 25 at any speeds faster than asa 12. Don't know the volume of that tube, but you will need 200ml for 5x7 at the 1:1:100 dilution. How did your film tests work out? tim in tucson

 

[k_jupiter]

tim, I don't expose Efke 25 at any speeds faster than asa 12. Don't know the volume of that tube, but you will need 200ml for 5x7 at the 1:1:100 dilution. How did your film tests work out? tim in tucson

tim in tucson,

To be honest, this is a new set of equipment, new camera, new film, new shutters and lens. New developer, new way of processing. The exposure could be anywhere from E.I. 6 to E.I. 50, hard to say not knowing the real shutter speeds.

This is the first step in pulling in a ballpark figure for expanding my test program. Now I take it that is 200ml per sheet? I am going rotary only because that's what I have for 5x7. All my 4x5 and smaller sheet and roll films are done in tubes in a tank (or on reels of course) using inversion processing. Development times for those are pretty easy to dial in.

I plan on using 5x7 negatives for contact prints and alternative processes, starting with cyanotype and working towards Platinum/palladium prints.


tim in san jose

 

[noseoil]

Sorry to take a while to get back. The rotary tank you are using may be too rapid and build contrast quickly. I've never used platinum or cyanotype, so my numbers for silver & azo won't match up with your process. I don't know how much contrast is needed relative to silver printing for these processes, more contrast or less?

If you are doing 5x7, I would urge you to make some 2" ABS tubes to work with. This will help dial in your numbers to existing times already worked out. Starting from scratch with rotary processing would probably need a reduction in dilution to 1:1:150 as a starting point, otherwise times may be very short.

I use 1:1:100 for tube development (BTZS type processing in a water bath) and 1:1:150 for minimal agitation. My "normal" exposure is at asa 12, but for azo I use asa 6 to get decent shadow values. Development times are still very short at 70f. tim

P.S. Whch camera & shutter-lens combination are you using for 5x7?

 

[k_jupiter]

P.S. Whch camera & shutter-lens combination are you using for 5x7?

I have recently aquired a B&J Grover 5x7 with a Gundlach Radar Anastigmat f 4.5 5x7 Ilex shutter and a Carl Zeiss Tessar 6.3 180mm Prontor Press shutter.

Coverage looks good on the GG but the proof is in the development pudding.

tim in san jose