Technical Pan Film

[robert_rossland]

I picked up a few rolls of technical pan film (TP-120) to try out on

my Pentax 67II. I have never used this film before, and according to

Kodak's publication P-255 this film is to be loaded and unloaded in

total darkness. I do not understand why a film with a speed of ASA-25

would need to be loaded only in total darkness. Does anyone have

experience with this film?

 

Thanks,

Robert Rossland

[triblett_lungre_thurd]

yes, do load in total darkness, and process in technidol or other very low contrast developer.

[don_feinberg2]

The reason for the "load in total darkness" is that Tech Pan has what is called "extended red" sensitivity. Not exactly an infrared film, but much more red/infrared sensitivity than ordinary pan films.

 

I've found that "total darkness" isn't necessary, but certainly very subdued light.

 

Also, be careful, if you are using 35mm: the base is estar-like can act like a "light pipe". If you rewind the 35mm film and leave the leader out, if you then take the cartirdge into a light place, you can fog the film inside the cartridge.

 

Before shooting, you should plan what developer you will use. Look at the spec sheet that comes with the film (or at the Kodak web site), and you will see that there is a very wide gamut of potential gamma available depending on which developer you use. The effective ASA of the film will also vary widely depending on what you use.

 

For pictorial use, use Technidol or Formulary TechPan developer, and rate at 20 to 25. (But, for example, you could develop it in D76 1:1 and get an average gamma of 2 -- great for copying a document...)

 

Don Feinberg

donf@cybernex.net

[brian_c._miller]

I have used a number of rolls of Tech Pan, and I have never loaded it in darkness. I have only put the camera in the shade. Of course, I have only used this film in 120 size.

 

I have had wonderful results with this film when it has been processed in Technidol. I have not tried it with diluted Xtol. From my experience, processing this film at the local film shop is a blatant request for tears (I know, I've shed some). Only process it yourself, and Technidol was made for it.

[paul roark]

I've used a lot of Tech Pan in both 35 and 120. I load it in shade -- just like any other film. I've never had a problem.

 

As noted, Technidol is the special developer that Kodak makes. It probably gives the best combination of grain and speed. The Formulary developer will give more speed but considerably more grain. Xtol gives incredibly fine grain, slightly less speed than Technidol, but it's much cheaper and easire to handle.

 

The major problem with TP, especially 120, is the evenness of development. Take some test shots that are pure, even gray. (I use a frosted acrylic over the lens.) Use Kodak's recommended agitation as a starting point. I find Xtol to be the easiest to control in this respect. It seems to give perfect evenness with 1 minute agitation and alternating vertical shakes with inversions.

 

By the way, I have an unopened block of 20 120 rolls of TP (as well as several other rolls) that have been in the freezer since I bought them from B&H. They are slightly out of date (4/99), but I'm sure that being frozen since purchase, they're fine. I'll sell them cheap, because I'm now shooting color. If you're interested, let me know off list.

 

Paul Roark,

proark@silcom.com,

http://www.silcom.com/~proark/photos.html

[pat_j._krentz_29_palms__ca]

I have shot TP 25 in 35mm at 100 asa and get very good negs using pyro, Kodaks SD-1 @ 1:1 for 8:00 after a 5:00 presoak, I cut the formula in half since I dilute it 1:1, I am in the process of doing some TP 25 test in 4x5 still using the pyro-stainging developer.

Pat

[gene_crumpler6]

Has anyone considered that loading a 120 camera in total darkness would be a problem in lining up the arrows with the marks on the film rails. I've had no problems handling TP in either 35mm or 120 size.

 

Kodak IR film in 35mm must be handled in total darkness because it has no anti-halation backing and light can "pipe" through the film. This apparently is why Kodak does not produce their IR film in 120 size. The Konica 120 film does not produce the "glow' or "bloom" that kodak does.