Silly question?

[nealjpage]

Are some MF films more prone to air bubbles forming on their surface? I've been having troubles with Fortepan lately. Never had trouble with any other film and my technique hasn't changed at all. It's really annoying.

 

[JamesD]

I've never had a problem with air bubbles, so I really can't say. However, pouring a little slower and tapping once or twice more a little harder might clear it up. Also, which stage is giving you bubbles? If it's the dev, are you "rinsing" the film first with plain water? Getting it wet first helps, they say.

 

[JC1220]

What kind of problems?

 

[nealjpage]

What kind of problems?

Well, I load the tank and add the chemicals. I rap it on the counter like I always do to dislodge air bubbles. I agitate the way I'm supposed to. Blah blah blah. But when it's all said and done, there's spots of film that haven't been processed. They're about the size of air bubbles.

 

[Hertz van Rental]

There is the possibility that they are not the result of air bells but are a film fault. I once had a similar problem with a batch of Jessop's film (which I think was made at the Orwo plant) - small round holes in the emulsion. I think that the emulsion coating had air bubbles in it when they applied it.
I'm not saying that this is your problem but it is worth checking.

You can pre-soak the film (remembering that this could result in a slight over-development. The emulsion being wet the developer gets in and starts acting quicker. Only worth worrying about if your processing is critical) or you can put a few drops of wetting agent in the dev.

 

[JC1220]

While most modern films suggest that you don't need to presoak, I think it is a good idea in promoting even development. If you do the same process each time you can adjust for any development changes that the presoak causes.

If you are getting pinholes in the emulsion, your fix may be too strong so cut it by 25-50%, and/or do a quick wash before fixing.

Or, switch to an alkaline fixer like TF-4.