Need help with Tech Pan Negatives

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I was recently shooting pictures for a friend and I decided to experiment with a roll of 35mm Kodak Technical Pan film. The other rolls that I shot were TMAX 100. The Tmax rolls came out perfect with good contrast and negative density. I was shooting outdoors in direct and indirect sunlight.

My question is about what happened to the Tech Pan negs. I have them processed only at a local lab and they said they use Xtol developer (not sure of dilution). The negatives came back with EXTREMELY high contrast and the highlights being washed out. I dont think my exposure was off because the shadow detail is excellent and when blown up on my enlarger it looks very sharp. I exposed the film at ISO 25. The Kodak technical info sheet for this film is confusing on how to expose it when you use Xtol to develop. So I think what happened was one of two things:

1) the negs were overdeveloped causing the highlights to go totally white (Zone X) or they were developed wrong. I have technidol at home but I was too lazy and busy to develop these negs myself.

2) I have exceeded the luminance range of the film and it couldnt handle the highlights. I have no idea what the difference in stops was between the shadow and the highlights (does anyone know the range of the film?).

I am intruiged by this films slow speed and was wondering if anyone had any experience with it. while the pictures I got from it were very "artistic" looking and my friend liked them, they do not make very good pictures in themselves. I would like to be able to take normal contrast pictures.

Thanks -- Micah

-- Micah Abelson (abelsm2@hotmail.com), July 19, 2000

Answers

Oh.. one more thing before to many people yell... I havent ruled out operator error. I could have goofed the exposure. I was under the impression that if I had great shadow detail like I have, then the exposure was at least partly correct. Maybe someone could correct me?

-- Micah Abelson (abelsm2@hotmail.com), July 19, 2000.

I have technidol at home but I was too lazy and busy to develop these negs myself.

That pretty much summs up your problem. Tech Pan is a tough film to work with. You definitely need to put the effort into processing it yourself if you want good negatives. The best low contrast results are procured by developing in either Technidol or TD-3 from the Photographers Formulary. I have never used X-tol on TechPan, but most developers produce really high contrast with TechPan. It takes more than one quick roll to get a good feel for how te film will work for you. Keep up the effort and you will be rewarded with excellent negatives.

-- Fritz M. Brown (brownf@idhw.state.id.us), July 19, 2000.


TechPan is very fussy with processing, and I doubt any B&W lab would do a good job with it. Don't worry, you haven't exceeded the luminance range of the film. I've got prints from TechPan with all shades from pitch black to pure white, and every shade of gray in between.

If you can't find Technidol, there is always Rodinal. I process TechPan in Rodinal at 24 deg C. Dilution 1:200, time 8 minutes. Agitation - once a minute. Works perfectly each time.

-- Sriram (r_sriram@bigfoot.com), July 20, 2000.


Technical Pan, as well as Kodak Ortho Lith, Agfa Ortho, is a high contrast film with a Dmax above 4. They are intented for line work not for continous tone. A straight developer as used as a replenished system by most labs will give a gamma value way above one.

BUT combined with special commercial developers like e.g. Kodak Technidol or Tetenal Dokufin these films can be used for halftone pictures, with gamma value around 0.5-0.7. These developers are pricey, so alternatives are Agfa Rodinal 1:150-200 for around 7-8 mins with only little agaition and Kodak Xtol document lists dilution, speed and time for Technical pan, I think it was 1:6, not sure.

In Rodinal I rate Technical Pan at 25 ASA, Kodak Ortho Lith at 12 ASA. 3 ml Rodinal for 2 films is also very cheap!

BTW, Technical Pan has a slighly extended red sensitivity, while Ortho Lith, well it is in the name, does not respond to red light at all. Both have a Dmin below 0.1, so negatives have to look thinner, since 2/3 of the base fog is missing.

Regards,

Wolfram

-- Wolfram Kollig (kollig@ipfdd.de), July 20, 2000.


Tech Pan is essentially a high contrast film, so by developing in it normal developer, you produced a high contrast result. By lowering the EI, and by developing in a highly dilute compensating developer such as Rodinal, the film can however be used for normal pictorial purposes, which many do successfully because of its extraordinarly high resolution characteristics.

-- fw (finneganswake@altavista.net), July 20, 2000.


When I talked with Kodak about 4 months ago, I asked the rep what to capabilities of their b/w film was, he told me that all b/w films made by kodak were capable of a 7 stop range, I use techpan once in while when I shoot 35mm, and I rate it at 100 and develope in Kodak SD-1 pyro, it give a beautiful tonal range and is tack sharp. Pat

-- pat krentz (patwandakrentz@aol.com), July 20, 2000.

> The negatives came back with EXTREMELY high contrast and the highlights being washed out.

That's pretty much the nature of the beast.

TP will easily record seven to eight stops on the straight-line section of its curve shape, but above that things get weird.

The film may be capable of a high D-Max when developed to very high contrast, but when we develop it to pictorial contrast not only do we lower the CI to a usable level, we drastically lower the D-Max. So what happens is that above about a Zone VII to VIII exposure there's a _very_ prominent shoulder, with the curve going pretty much flat horizontal within a stop or two above that.

That's blocking; there is no significant contrast increase upon exposure increase.

Or iow, if you give a "full" exposure for shadow density, if the SBR is high enough you may easily push the light tones up onto the shoulder; this prints as pretty much blank white with no detail. If you burn it in, you end up with detailless grey.

The location and extent of the shoulder varies with developer; Xtol behaves exactly as I've described, with a rather early shoulder.

The best developer I've found for TP is C-41 developer (just the developer, not the entire process), use ordinary inversion agitation, 9'/75F for EI 12-25. It gives the longest straight-line curve section.

-- John Hicks (jbh@magicnet.net), July 20, 2000.


I've been shooting bulk loaded tech pan for about 10 years. It is the only 35mm B&W film that I use (other then a couple rolls of kodak HIE now and then). Two other developers that work with tech pan are Ethol TEC at 30:1 and diafine with 45-60 second development in the "b" solution. Both yield an EI of 100. The beauty of diafine, is agitation, temperature and time are not critical for most normal contrast films. With tech pan you shorten the "b" time to control contrast.

Both are dirt cheap compared to technidol. Diafine is great for those of us that find film development not very creative.

-- Gene Crumpler (nikonguy@worldnet.att.net), July 20, 2000.


You might also want to give this a try: Microphen diluted 1+5, EI 32, develop 14 min. @ 75F, agitate 5/30 sec.

-- Tim Brown (brownt@ase.com), July 20, 2000.

Expose at ISO 25, and send to The Photo Factory in San Diego for proper development in Technidol. www.photofactory.com

-- Bill Mitchell (bmitch@home.com), July 20, 2000.


If you send it to The PhotoFactory or any other lab be sure and specify Technodol "and" a normal minus one development. Unless you specifically ask and "pay" for the service all you will get is their house soup and times. Do it yourself and always be satisfied. James

-- james (james_mickelson@hotmail.com), July 22, 2000.

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