stains on my BW negs (water? flo?

[bessa_L_R3a]

Hi,

When I´m done washing my negatives I pour in the photo flo and slosh the reels around in the mix for a few minutes, then I take out the negatives and hang them up to dry. Once dry, I see these grayish, amorphous streaks running down parts of the negatives. They look terrible and are difficult to remove. How can I solve this problem? When I scan the negatives, the streaks do not seem to show up, though, but I would still prefer to have cleaner negatives.

What would happen if I didn´t use photo flo? Or am I using photo flo incorrectly?

Robert.

 

[bobwysiwyg]

What sort of mix ratio are you using for the photo flo?

 

[bessa_L_R3a]

What sort of mix ratio are you using for the photo flo?

I am mixing 5mL of photo flo with 1,000 mL of water.

 

[bobwysiwyg]

One thing could be the water, but judging from your location, I'm assuming you are using municipal water, which should be OK, but if you think it could be the water, try distilled for this step. I only use a few drops in the same amount of water and haven't had problems.

 

[bessa_L_R3a]

do you think it´s bad for the scanner to scan negatives with the filmy schmutz on it? i mean it´s pretty thin to begin with.

 

[bobwysiwyg]

I don't think it would be a problem. The worst that can happen is something gets transfered to the glass bed (platen?) and you might have to clean it, but if the surface of the neg is dry, even that shouldn't happen.

 

[srs5694]

You said you "slosh the reels around in the mix for a few minutes." I've found that if I leave B&W film in Photo Flo for more than about half a minute, I get problems with drying marks. I therefore limit Photo Flo time to 30 seconds. I also use half the specified dilution (2.5ml per 1000ml) in distilled water. This produces good results for me.

 

[jasonjoo]

I used to mix up Photoflo and store it after each use but I've noticed a lot of floaters lately, so I simply add a few drops now into my trays/inversion tank. No issues so far.

 

[Trevor Crone]

Robert,

There's this wonderful wetting agent from Rollei called RWA SC, I don't know if this product is available in the States. But it has made my 'film life' a lot easier and reliable. It's super concentrated, use 1ml to 1L for a working solution. I mix it with just ordinary tap water (hear in London the water is very hard), no need for distilled or de-ionised, and leave the film to soak without agitation for 2 minutes. Drain and just hang to dry in a dust free atmosphere. The result is super clean negatives from 35mm to 8x10's.

Believe me I've used many wetting agents, but this is something else.......no hype, if you can get it try it.

Trevor.

 

[Rick Jones]

When you first hang the film to dry hold it at a 45 degree angle for a full minute allowing the water to flow off the lower edge of the film. If that doesn't cure the problem start reducing the amount of Photo Flo to water. I have found Edwal's LFN easier to control simply because they market their 3/4 oz size in a squeeze bottle that dispenses a drop at a time.

 

[stu]

I had the same problem with my negs when I moved into a new area with my darkroom. I tried using a normal Brita filter (as in the drinking water kind as I don't have running water in my darkroom) and it sorted it out! Worth a try.