Pan F developing strangely

[ricster]

Hello all,

Just wondering if anyone can shed light on why some of my rolls of Pan F appear underexposed / under developed.

I've been using a 3 spool Paterson tank and haven't had any problems with HP5+ or FP4+ film. But recently I've had 2 rolls of Pan F that appear totally underexposed. In one batch of 3 rolls of Pan F, 2 rolls came out fine but the third appeared under-exposed - except that the film identifier and frame numbering along the edge came out equally underexposed / under developed (same as the frames). The same happened again on the next batch of Pan F that I processed (a few weeks later).

Any reason why this should happen?

Cheers,
Alaric

[Wheelu]

I may be wrong, but if the film identifier is undercooked doesn't that mean that the film is underdeveloped? I have always assumed that the markings were exposed when the film was manufactured. Alternatively it could be severely old film of course.

[huwevans]

Well, the obvious response is to ask if you're sure the dev wasn't exhausted, or too dilute for the dev time, or too cold, etc. Although I can't think of anything that would account for a significant difference in rolls processed in the same tank at the same time - that's a perplexing one.

[Wheelu]

Thinking further about this, and assuming that it is underdevelopment, and that you are using a 3 roll tank and that one roll is underdeveloped. Doesn't this point to an insufficient volume of developer solution? Was the problem roll on top of the heap?

[ricster]

Only once have I not had enough dev in a tank and the results weren't like this - and after that it made me make sure there's always enough ;-)

It's really strange as the other 2 rolls in the tank at the same time were fine.

About the only thing I can think of is if the film got too hot prior to developing??? What effect would that have?

And thanks for the swift replies!

[taxor]

What kind of agitation method were you using? If you're using the twiddle-stick method and standing the tank in a bowl/bucket to stabilise the temperature, you really need to make sure that the surrounding water comes up to the level of the dev in the tank. If you think about it, the developer sitting above the level of the water jacket may be running a degree or two lower than the rest below the water line for the bulk of the development time. You should do this whichever method of agitation you use. I had a similar problem with Agfapan 25 some years ago. The bottom half of the film was correctly developed but underdeveloped on the top half. The only difference I made (which rectified the problem) was to ensure the water bath was up to the level of the dev. Oh, I also changed from using a twiddle-stick to inverting the tank - which also probably helped. Never had a problem since.

[Gordon_McGeachie]

were all 3 films exposed the same, and one of them not under or overexposed by you and not processed accordingly?

[ricster]

were all 3 films exposed the same, and one of them not under or overexposed by you and not processed accordingly?

I can understand if I didn't expose them correctly, but the film ID thing along the edge was as faint as the images themselves which is what is confusing me - the other 2 rolls in the tank came out as you would expect.

I'm fairly certain the film came from the same batch.

[John_K]

What developer are you using? I ask this because I was told by Ilford that some of the developing times on the instructions for their products are incorrect. Also the times published on the insides of the film boxes supplied by Ilford are also wrong.
If you go to the Ilford website and download the developing charts these are accurate and that is what I use.

[ricster]

Hello John_K - I'm using microphen.

As it was only 1 film out of 3 the only thing I can think is if that one roll somehow got very hot before I developed it: would that cause this? I know that film doesn't like heat??

I didn't stand the dev tank in water, and as the film is uniformly underdeveloped it was certainly covered with sufficient developer - and the other 2 rolls came out fine.

I'll just mark this down to experience and see if it happens again: if I ever get to the bottom of it I'll let you all know!

Many thanks for all your hints, tips and comments!

[PeteE]

Well, I did a lot of processing for a member of ePHOTOzine who didn't have darkroom or chemicals and his Kodak T-max 100 was perfectly exposed in a Nikon F65 BUT when he sent me Pan F the negs were incredibly THIN and I get good results when I take PanF although it's all outdated, and his were really FRESH! I had to contact him to get him to check to see if he had the exposure compensation set to -2 or something. Never found out why- maybe a bad batch of film?

[apochromatic]

I've been processing PanF on and off for years and it is the least predictable film I have ever come across. I'm almost pleased to hear someone else is having trouble with it. It's a hateful film and I stick to Delta or FP4 which seem much better. I bet you don't use it again.