orthochromatic film

[daniel_luu_van_lang]

Hi all,

Did anybody already use the orthochromatic film Bergger BPFB-18 in

the field? I use this film in my darkroom for alternative process but

I wonder if I could load it in a holder and shoot with it. According

to what I've read in Ansel's "Basic photo ", it's possible but what

about the sensitivity? Help!

[steve_feldman]

Daniel,

 

Orthochromatic film is used in the printing industry. Extremely high contrast and very slow. Litho film sees medium to light blue as white, red and orange as black.

 

You could use it in a 4x5 holder . . . but why?

 

When I need a litho film for contacting I project a camera neg, of any staring size, and project it on to lith (ortho) film for a positive and then contact again to litho for a negitive. Develop under red safelight Dektol 1:1 68 deg 3 min.

[david_clark4]

Hi Daniel, I've some experience with the Ilford Ortho in the field. Ortho works fine, of course you wont be using a red or orange filter and the skys will be bleached out. The Ilford film has a stiff back and so it doesn't sag in the holder. Best, David

[hal_hardy]

You might also try a Kodak #44A gel filter. It will turn regular pan film into a near ortho film with a normal contrast range.

[arne_croell]

Sorry, I haven't used the Bergger film. I did play around with Ilford Ortho (old version) several years ago, developed in PMK. The skies are light-coloured and reds are dark, but otherwise it worked like a normal film. A bluegreen filter (like the Wratten #44A already mentioned) on panchromatic film has a similar effect though. Also, Kodak used to make an orthochromatic version of Tri-X, which is no longer available.

None of those, however, were lith films as mentioned above. While all or most lith film are probably orthochromatic or just plain blue sensitive, not all orthochromatic film is lith film. Some other films, like the now discontinued Agfaortho were line films and needed special developers like Technidol for pictorial work.

[mehmet kismet]

Hi Daniel,

 

I use Bergger BPFB-18 since a long time for making unsharp and/or shadow/highlight masking films together with from time to time Kodalith Type3 #2556 film.

 

Even if I hade never used it in the field, the comparison I have made with Tmax100 for the same purposes,(unsharp masking film) showed me that Bergger has an approximative EI of 6-12 in the darkroom circumstances. My procedure of unsharp masking exposure is to contact printing through the antihalo layer of the Bergger with the tungsten halogen lamp of my Durst L-1200 and with a filtration of 20M30C. You should test it in daylight of course. And my exposure comparison is made with Tmax100 which is a very proportional film in the reciprocity failure range.

 

All these parameters evaluated, a starting point for daylight should be as EI 6 developed in Rodinal 1:75 for 12minutes at 20o Celcius.

 

Good luck