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Tiny pinholes, in the sky. Wasn't that a Don Ho song ? Anyway. I'm getting scattered pinholes in my FP+ negatives developed in HC110. I handle the damn sheets like they were nitroglycerin from loading to developing. They are tray developed and don't touch each other during processing. The tray bottoms are smooth and clean.
They are NOT dust specks. They are white holes in the emulsion. Any ideas ?
It could be a bad batch of film, but that's not very likely. It is more probable to be an acid/base reaction producing CO2 bubbles in the emulsion. First step: mix all chemicals fresh, use only distilled H2O (including the presoak). Measure your stop concentration very carefully, or just use a water bath. If you've still got 'em, have a sheet of film processed commercially to see if the problem is in the film.
More info - I use a water pre-soak, water stop bath and alkaline fixer (Photog's Foundry.)
White holes in the emulsion could be from dust on the emulsion. Are there lots of very tines holes, or isolated, larger ones?
Piholes from processing usually come from the stop bath, but if you are using a water stop bath, that's not it.
I suggest that you process an unexposed piece of film and see if the holes are there. If they are, it is a processing problem. If they are not there, it is a problem that occurs during exposure--from dust.
In addition to Mike's suggestion, can anything be flaking off the inside of the bellows. I see "this" a lot when using old folding cameras until I've gotten hold of all debris, loose stuff. GOOD LUCK narrowing it down.
Gene,
It does sound like dust from the above descriptions. Dust is the bane of all our existences, and can sneak in at many unexpected points in the process. I'm not sure if this will help, but here are a few of the less obvious causes of dust spots that I've had to deal with.
There is always airborne dust in the loading environment. You can minimize it and the film's exposure to it, but not eliminate it. Changing bags are the worst, since you have to move everything around inside to use them. I keep an air filter running in my darkroom for hours (sometimes days) before loading. Then, after vacuuming and covering the holders and wiping down counters, walls and floors with a damp cloth, I turn off the filter fan, fill the sink with hot, steaming water and sneak out, carefully closing the door behind me. I let the darkroom stand this way for an hour and only then do I carefully tiptoe in and begin the loading process. This seems to help settle the dust somewhat.
Just to be sure, however, I always keep the film stack face-down when loading, turning the individual sheets face-up just long enough to tap them on the counter and slip them into the holders. This minimizes the exposure time to airborne dust.
Also, there can be crud packed with the film, usually small emulsion crumbs from the cutting process. Tap the edge of the film sheet on the counter (away from the holders) before loading to knock them off. You may be surprised at the pile of black crud on your counter when you turn on the light.
Check all your holders for dust in the light traps. Vacuuming helps, but sliding a damp dark slide in and out past the trap numerous times and/or using compressed air (or an environmentally-friendly compressed gas product) usually turns up more specks. I vacuum my holders before each loading using a small vacuum cleaner equipped with hepa filters to prevent dust from simply being blown through and back into the air.
After loading, get those holders into dust free containers. I use new quart-size zip-loc type freezer bags. one for each holder.
Despite all the above precautions, there always seems to be a bit of dust on the holders when I pull them out of the plastic bags. I carry a small lipstick brush for whisking away the dust on the outside of the holders before inserting them into the camera.
Clean the inside of your cameras. If you haven't done so in a while, you'll be surprised at the amount of dust in there. The laws of physics state that the dust inside cameras remains in a state of quantum flux until you pull the darkslide, which collapses the probabilites and causes them all to affix themselves to areas of contiuous exposure on the negative (i.e. the sky). Pulling the darkslide slowly can often fool these dust particles into remaining in flux.
Once the exposure is made, you can relax, but get the holder back into its protective cover to keep it from gathering dust that can ruin the next negative.
These are a few possibilities for dust. There are many other obvious ones as well as some I can't event think of, but this routine has helped keep my pinholes to a minimum. I apologize in advance if dust turns out not to be your problem. Hope this helps you or some one else.
Regards.
Most of the time, this is due to a to strong dilution of stop bath. The acid is reacting with the alkaline developer and burning holes... it always happend in the sky... go figure! Instead of a stop, use a water bath. If this isn't the case, FP4+ and HP5+ seems alot more sensitive to changes like this, it could be a bad batch of film.
Greetings Gene,
It may be the film??? While I hesitate to say this, because I can't prove it, I've seen some tiny pinholes in 8x10 FP4+ as well. I don't use an acidic stop and my process remains alkaline from start to finish. The pinholes I've encountered are exteremely small and are not caused by dust. Other films that I have loaded in the same environment do not exhibit this problem, so I'm inclined to think that it's a manufacturing defect. It occurs only rarely, otherwise I would have complained to Ilford. BTW, I process the sheets in a Jobo, so there's no chance of scratching the sheets.
Regards, Pete
I'm obviously coming into this thread rather late, but I've seen similar pinhole problems with the few sheets of T-Max 100 & 400 that I have used - most of them had pinholes in them. I rarely see pinholes with my FP4+ and all films are handled in the same way, in the same changing tent(s) and developed using the same chemicals..