Just processed a test roll of 120 PanF+ in PMK and notice that the film base appears different than the FP4+ and HP5+ film bases - appears as though there's a random fog pattern over the entire film (including interframe gaps) but it's NOT fog on the emulsion - appears like a random, murky fog with a slight overall pink tinge the film base.

Initially thinking I'd underfixed the film, I tried re-fixing (TF-4 alkaline fixer) with no change resulting. It doesn't appear to have an effect the image, but not having expected this with a slow film, I'm wondering if this is usual for this film, or whether I've got a defective roll.

-- David R. Williams (davidw@ca.ibm.com), June 17, 2001

Answers

Greetings,

My experience with Pyro developers is quite limited, but I don't think your results have anything to do with the developer. I have used all of the film you named and Pan F+ behaves much differently than HP-5 or FP-4 in terms of antihalation clearing. In "standard" developers, both HP-5 & FP-4 will produce a nice clear film base in Kodak Rapid Fixer, whereas Pan F will have a pinkish coloration. This is usually attributed to insufficient fixing/washing. You tried refixing, but perhaps were unsuccessful due to the Pyro staining - sorry, but I don't know enough about the side effects of the Pyro developer. That pink tinge is characteristic of T-grain films and Pan-F that have been insufficiently fixed and/or washed. You may want to stick a piece of unused film in TF-4 and time how long it takes to clear.

Regards,

-- Pete Caluori (pcaluori@hotmail.com), June 18, 2001.

David, I'm not familiar with Pan F+ processed in PMK, so I can't comment on the base color you are getting. The fact that you say the fog pattern is random makes me think that the film was old or exposed to high heat. This type of fog pattern is consistant with film that was not processed soon after exposure, especially when kept in areas of high temperature and low humidity.

Regards, David Carper ILFORD Technical Service

-- David Carper (david.carper@ilford.com), June 22, 2001.

David - thanks for your response. I'd thought about the same issues when I first saw the "fog", it appears as though its present only on the film base, not on the emulsion side - this is what leads me to believe it's not a true "fog" in the sense of an emulsion problem, but rather a film base material issue. Re-wetting the film base side makes the "fog" disappear, while rewetting the emulsion side has no effect.

The film was exposed immediately after purchase from a local retailer (that stores film carefully) and had an expiration date in 2003. The film was processed within 6 hours of being exposed.

Could this simply be a characteristic of 120 PanF+ using a different film base material than FP4+ and HP5+? In your experience, does a Pan F+ neg appear different from FP4+ and HP5+ negs?

-- David R. Williams (davidw@ca.ibm.com), June 22, 2001.

Hi, I know this is an old question, but I'm responding anyway. Yes, the film base of Pan F looks strange. Lars Kjellberg at Photodo made a test of B/W films in a magazine in the early 90's. He saw many micro-small bubbles in the Pan F film base. I looked in a microscope and saw the same last week. :-/

-- Patric (jenspatricdahlen@hotmail.com), May 10, 2002.