pinholes in Neopan 400

We've got pinholes.

Pretty bad too! So far it has only happened recently since I started using Neopan 400 more (120 format). I have only noticed it in Neopan 400. It has happened with both Diafine and D76 1+1. I use stainless steel tanks and reels and mix my developers with distilled water, and I use Arista Odorless rapid fixer diluted 1+3, and I have a tendency to fix for a long time (5-20minutes). I don't use an acid stop bath.

The only thing I can think of is that the pinholes are being caused by overfixing, or else my camera is damaging the emulsion. These were all taken with the same camera.

20 minutes?!!

Pinholes would be a difficult thing for a camera to produce, they'd be long scratches if anything. But, dust maybe?
Shoot another roll and fix for 5 minutes, so we can eliminate that. It shouldn't need 20 minutes of fixing, but I couldn't say how that would cause pinholes either.

I usually fix that long because I have a tendency to just go do something else after I pour the fixer ind and agitate it a little bit. I've seen tests that showed it was impossible to overfix within any reasonable <12hr time, so I just don't worry about fixing a long time. Virtually every other frame from recent rolls seems to have pinholes in it to some extent. In these you might be able to see the pinholes in the sky and parking lot of the first (mildly cropped) image; the roof of the building on the heavily cropped second image, and lots of small pinholes on the wall of the full-frame image of the laboratory, in this case more obvious in the print.

Do you use a stop bath at all?

If you change from Alkali (Dev) to Acid (Fix) too fast you can generate "Blow Holes" in the film - normally in the dense parts of the Neg (usually the sky)

A very weak acid stop bath or a plain water intermediate bath might be worth a go.

Also, is the inside of your Camera and Film Back scrupulously clean ? - dirt in the camera gives the same affect as Pinholes/Blowholes

Martin

I think now, that it's more likely that the "pinholes" are due to bits of junk on the film. I have seen little bits of black junk on the film but I thought it was coming from the roof of my dark-closet. It seems more likely now that they are bits of bellows. The camera is a folding camera with a deteriorating bellows. A new bellows is $75 and I that's too much for me to afford, so I think I'll just make sure that I blow the camera out with canned air and hope for the best.