Kodak Techpan

[Robert Kennedy]

Out of sheer curiosity, I got two rolls of 120 Techpan this week. I have never used this film. Any suggestions? I am assuming it will be like shooting Pan F....

 

[David A. Goldfarb]

I haven't shot it in years, but I got nice results in Technidol, pretty much following Kodak's instructions (somewhere around EI 25-32, if I remember correctly). I think TechPan's characteristic look comes as much from the extended red sensitivity as from the fine grain. It's great for detailed landscapes and good with the usual filtration for well-defined clouds, and I've even seen some nice portraits with Tech Pan.

 

[bmac]

I'll second Technidol. Do you have any? If not, I think I have a few packs of it left. I can send you one or two.

 

[Les McLean]

The same happened to me a few years ago, I was given two rolls to play with and dev'd them in Technidol as per instructions and the negs were fine.

 

[fparnold]

It made the best-looking B&W slides I've ever done, as I remember, when processed with relatively simple reversal chemistry. The extended red is nice, and it's amazing the skies you'll get either without filtration or with simply a #8. 120-sized slides from it would be a sight worth seeing.

OTOH, it's a thin-base, curls like mad, and is sharp enough that it will show you camera shake you didn't think you had. Maybe in the bigger 120 rolls, it won't be so bad, but in 35mm I feel like I'm holding a garter snake while cutting it.

BTW, an alternative to Technidol is X-Tol 1:2, 6 min @68F. The Massive Dev Chart will have the exact time, but I used this recently on an old roll, and the negatives are outstanding.

 

[Black Dog]

Have a look in the low contrast section of the Film Dev Cookbook (Anchell + Troop).I'd also recommend Rodinal at 1+200 ish -this worked v well with Maco ORT 25 for 10 mins at EI12.

 

[fhovie]

I switched from Technidol to TD3 and am never turning back. It really makes 35mm look like MF for enlargements and I really like how it sees colors. I accidently developed some Techpan in Split D-23 and the negatives were very printable - about N+1 or maybe a little more but quite usable.

 

[Roger Krueger]

I'm a TD-3 convert too. In addition to its other virtues, TD-3 is hard to screw up, compared to Technidol, which is pretty touchy. Also, Technidol gives a very abrupt shoulder; TD-3 gives a shoulder that goes on forever.

As a staining developer, TD-3 works a little better in an alkaline fix like TF-4, but looks fin ordinary fix too.

The only downside is for the chemically fearful: it is pyrocatechin-based. As long as you're not tray processing with bare hands it's not that big a deal.

 

[Black Dog]

I suspect that the TD -103 formula in the Film Developing Cookbook is similar to TD-3. It's 5g sodium sulphite, 10g pyrocatechol (sol A) plus 150-200g sodium carbonate in sol B (potassium might be better). Dilute 1+9 and develop for 10-15 mins at 20c (rate TP at 32-50).I'm going to give it a go as I already have all the ingredients (the sulphite could be replaces with bisulpite btw).

 

[Adrian Twiss]

I had a devil of a time loading it onto the spiral (Paterson type) because the emulsion is so thin. I was processing a 35mm roll. I must have got something wrong because it fell out of the grooves with the vigorous agitation and was ruined. Take care with your loading.

 

[MikeK]

Another developer you can try with Tech Pan is C-41. It works quite well.

- Mike

 

[Black Dog]

Yes, I've seen that mentioned several times. What time/dilution/speed etc?

 

[djklmnop]

http://www.sbccphoto.org/show_Tip.asp?ID=1

 

[MikeK]

Sorry for the delay but I had to dig through 15-16 years worth of notes. It's been that long since I seriously used Tech Pan.

Ok rated at an EI of 25 I developed for 9 1/2 minutes in C41 developer at a temperature of 70C. I used the developer from the Beseler Color Kit as well as begging a liter once in a while from my local pro-lab.

Rinsed the film and fixed using regular fixer. I would suggest you shoot a few test rolls first. I am looking at some 120 negatives I took in Greece, normal contrast with good shadow detail.

Hope this helps

- Mike

 

[Tom Hoskinson]

After a long hiatus, I have begun using Tech Pan again (a friend gave me an out-of-date 50 sheet box of 4X5). I used Tech Pan extensively in the late 1970's and early 1980's, developing it in POTA and a buffered POTA variant of my own devising. My results were excellent but EI's were very low.

I have been using Pyrocat-HD with Delta 100, Pan F+, Acros 100 and TMax 100 with outstanding results. I have also been testing a variant (suggested by Patrick Gainer) with these films that replaces the catechol 1:1 with Hydroquinone and eliminates the bisulfite and bromide (results - so far -are fully equivalent with Pyrocat-HD). I have been testing Tech Pan in this Pyrocat-HD variant developer and the results have been excellent.

Solution A:
Phenidone: 0.2 grams
Hydroquinone: 5 grams

Dissolve these chemicals in a small amount of methanol, then add Ethylene Glycol to 100 ml and mix (I do these steps under a ventilated lab hood wearing Nitrile gloves). The Ethylene Glycol acts as the preservative, so the bisulfite is not needed. I am not having film fog problems, so I eliminated the bromide, as well.

Solution B:
Potassium Carbonate: 100 grams

Dissolve the carbonate in 70 ml of boiled deionized or distilled water. The resulting volume of solution will be 125 - 135 ml.

As a starting point, try an EI of 64 and develop in 10 ml of A plus 10 ml of B plus 1000 ml boiled deionized or distilled water (the resulting one-shot solution will be a yellow-amber color). This is the 1:1:100 dilution. In a small tank or tray, develop Tech Pan for 12 minutes at 21 deg C with no agitation. Rinse with water and Fix in a non-hardening Fixer (I use TF-4).
The resulting D-Log E curve is similar to the ones produced by Tech Pan developed in POTA and Technidol.

If you look at the Photographer's Formulary Modified Windisch Developer, the working solution concentration of catechol is .3125 grams/liter. This suggests that a 6:6:1000 dilution of Pyrocat-Hd or the Hydroquinone variant would also work and my initial tests with this dilution confirm this. A suggested starting point is an EI of 64 for Tech Pan developed for 16 minutes with no agitation at 21 deg. C.

 

[Donald Miller]

Tom,
Thank you for posting the results of your testing.

I wonder about your statements of equivalency to Pyrocat. Have you done any densitometric testing and if so how do you account for the fact that your formulation does not provide any proportional stain?

Thanks again.

Donald Miller

 

[Tom Hoskinson]

Donald,
I have perfomed densitometric testing on both formulations and have microscopically (optical) inspected the negatives - film from the same emulsion numbers, exposed the same and developed in both developers.

The Hydroquinone version of Pyrocat-HD does provide proportional staining and tanning (as it should with no or low sulfite). The stain image is a slightly different color (from the Pyrocatechol version) but otherwise is very similar.

To quote Patrick Gainer: "Hydroquinone is 1,4-dihydroxybenzene. Pyrocatechol is 1,2-dihydroxybenzene. According to theory, any developer with two or more active hydroxyl groups will be an active tanning and staining developer."

Gainer cites "The Theory of the Photographic Process": Chapter 13: "The Developing Agents and Their Reactions" by W.H. Lee.

See "The Role of Antifreeze in Photographic Science" by Patrick A. Gainer in Volume 25, No. 2 of Photo Techniques, March/April 2004.

 

[Donald Miller]

Tom,

Thank you for that explanation. What were your measurements of the proportional stain density of the Hydroquinone based developer that you formulated when read through the blue channel and if you have it, the UV stain density as well when compared to the visual density?

Also the comparative values of the Pyrocat developer with the same readings.

This may be of interest to those who have an aversion to catechol or pyrogallol based developers.

Thanks again,

Donald Miller

 

[Tom Hoskinson]

Donald,

Good suggestion.

I only have the visual density readings now, but will get back on the densitometer next week, get the other data and post it.

 

[Tom Hoskinson]

Donald, it took longer than I expected. I ended up using a 12% Stock Solution of NaOH in Deionized Water as the alkali and two 1% Stock Solutions: Catechol and Hydroquinone in Ethylene Glycol - no sulfite or bromide - as the developers. Here are some results for 120 roll Kodak Tech Pan. The working developer is 3 parts Q or C stock soln plus 1 part NaOH stock soln plus 100 parts deionized water. Stand development in a tank was for 20 min. at 70 deg. F. Here are the densities for Hydroquinone:

Visual Blue Channel
.03 .03
.12 .16
.33 .41
.48 .62
.60 .74

The results for the Catechol developer are similar.

Visual Blue Channel
.12 .15
.35 .42
.48 .55
.60 .67
.71 .79

 

[Donald Miller]

Tom,
Thank you for your work and for reporting the results. This is interesting. It would seem that the hydroquinone developer does not support shadow separation as well as the Pyrocat developer. What I am wondering, in light of the initial hydroquinone developer density reading (.03) is what the film base plus fog reading was for the film. It would appear that the hydroquinone developer also effects film speed. What are your thoughts on this?

 

[Tom Hoskinson]

Thank you Donald.
You are correct.
Both hydroquinone and catechol, when used as single component developers like the ones I tested, produce overall and proportional stain, but do not produce the shadow separation that they produce when combined with phenidone (with the resulting additive effects). An additional consequence is a reduction in effective film speed. Another consequence is a reduction in developer activity.

The result with Kodak Tech Pan is an EI of about 25 and a D Log E curve like the one POTA produces.

 

[Tom Hoskinson]

Donald:
The Visual Channel base plus fog was 0.19 and the Blue Channel base plus fog was .20 (as I recall - I will go back and double check the numbers).

The film was fresh Kodak Tech Pan 120 Roll with a 2005 expiration date.

My Stand Development procedure: In a filled tank with 20 seconds of initial gentle torus inversion agitation. No agitation at all for the remainder of the 20 minutes.

Rinse (no stop bath) was for 1 minute in 18 megaohm deionized water. Fixer was TF-4 (alkaline - non hardening) for 4 minutes.

 

[Donald Miller]

Donald:
The Visual Channel base plus fog was 0.19 and the Blue Channel base plus fog was .20 (as I recall - I will go back and double check the numbers).

The film was fresh Kodak Tech Pan 120 Roll with a 2005 expiration date.

My Stand Development procedure: In a filled tank with 20 seconds of initial gentle torus inversion agitation. No agitation at all for the remainder of the 20 minutes.

Rinse (no stop bath) was for 1 minute in 18 megaohm deionized water. Fixer was TF-4 (alkaline - non hardening) for 4 minutes.

Tom,

I guess that I am not tracking with you here. When I look at the first two density levels that you reported in your initial visual and blue channel comparisons for hydroquinone and for catechol the densities are below what you said FB+fog are. What am I missing here?

 

[Tom Hoskinson]

Donald:
The densities I posted are the delta densities over the base + fog.

My densitometer (a Macbeth Color Densitometer) has a function that, given a base + fog sample, measures the density, stores it, then calculates and displays the deltas for additional samples until the function is reset. I did separate base + fog measurements for both the visual channel and the blue channel.

Sorry for the confusion.