macophot IR film

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my photo shop has recently started stocking the macophot infrared film, distributed by cachet. i've looked at the macophot and cachet websites and searched the photo.net forums, but i haven't yet been able to find any definitive information on exposure and development. i realize this film is rather new and still somewhat rare, but i'm wondering of anyone has used it with good results. i've only used kodak's HIE and have seen quite a bit of work on ilford's SFX. how does it compare with these films?

the macophot website suggest an *unfiltered* starting EI of 100, which would be an EI of 12 with a red-25 filter.

XTOL seems to be the developer of choice. macophot suggests XTOL 1:3, 70 degrees, 14 minutes, agitation every 30 seconds.

any help will be greatly appreciated.

best, brad daly

-- brad daly (bwdaly@hiwaay.net), September 29, 2000

Answers

I encountered the same problems that you describe. There was one article in a German photo journal, which was very disappointing in that there was no definitive information in it either. The only thing that you could draw from that was the suggestion to try and expose and developt the film as you would do with HIE. Besides that, you will probably have to bracket a lot for the first film. I haven't got round to test the film yet, but hopefully I will be able to do so on a trip next week. When I can give some specific information, I will post it here.

-- Thomas Wollstein (thomas_wollstein@web.de), September 29, 2000.

I have so far shot three test rolls. This film has ... quirks.

The first two rolls were shot together, along with two rolls of Ilford SFX. I used the filters I normally use with Ilford, Konica, and Kodak.

Data:
Film speed: ASA 100
Development: Xtol 1+3, 68F, 14 minutes.
Each filter was tested at brackets of N, +/-1, +/-2, and +/-3.
FilterFactor (+stops)
B+W 090 (25)+2
B+W 091 (29)+2 1/2
B+W 092 (89B)+3
Tiffen Orange #16+1 1/2
No filter+0

Impressions:
The antihalation layer comes out with a wonderful blue-green color, and the hypo clear and subsequent wash also remove some more blueish dye.
Combining the filter factor and the speed seems to give a decent exposure. If I want to get more precise, I will have to set up an actual scene with a test chart to photograph.
The N bracket seems like a normal B&W negative, i.e., nearly no infrared effect at all. The main IR effect comes out at the +2 and +3 brackets, but they exhibit blooming and are overexposed.
I developed one roll in a steel tank and used shaking up & down agitation, and the other roll in a Patterson tank and used twizzle agitation. The roll developed in the Patterson tank exhibits pinholes. Both tanks were tapped on the counter after agitaion to remove air bubbles which might have adhered to the film.

The third roll was developed as above, in a steel tank. I used a home- made IR filter made out of a slice of E-6 and Kodak #29 filter. The available light measured at ASA100 was F11 and 1/125s. I gave the filter +4 stops for N, and the best brackets were +2 and +3. The negatives were not overexposed, and they look very good.

One problem during development: I left this in the presoak (over 15min) and wash (20min) too long. The emulsion swelled considerably, and this produced a haze/sudsy/cloudy appearance throughout the film. Most of it went away when the film dried out, but I wouldn't make anything but test prints from these negatives. The other two rolls had a presoak of 1min, and a 5min wash after hypoclear.

Impressions so far: I think this film is best only with opaque IR filters. Anything else, and the film will be overexposed in order to get a decent IR image.

I sent my results to the people at Cachet, and they said that the best results they had seen so far had been developed with D-76.



-- Brian C. Miller (brian.c.miller@gte.net), September 29, 2000.

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