This one Dan. I'm not very scientific, it just works for me. I often use a little more flo than normal and eyball the amount of rubbing alchohol. The less stuff I do before a printing or processing session, the better (like mixing flo).
one other thing - is it ethanol or isopropol alcohol? Also, how much difference does it make in your drying times?
Emancipate yourselves from mental slavery;None but ourselves can free our minds. - Bob Marley
I think I'll just stick to the photo-flo. I didn't know anything about its preservative properties, so I'm glad that was mentioned.
My bottle is getting low. I'm guessing it'll run out in three or four years. To be honest, I did think it was getting low, but I didn't stop to think how little of it I use and how long the remaining solution will last...
I wouldn't want anybody but photographers to know this, but I have been known to misuse some of their liquid detergent. It's a bit like my pink pajamas. The ones I wear in the summer when it's hot, in the winter when it's not, and sometimes in the springtime, and sometimes in the fall, I jump right in between the sheets with nothing on at all.
I think that might be more than we needed to know...
Originally Posted by gainer
Actually, I have not used anything but a fresh paper towel or a soft cloth, like an old fashioned diaper, with which I gently remove the surface water film. I have not had any problem with scratches or water marks, or even the mineral content of my well water. If this be treason, make the most of it!
I have 35 year old negatives that were rinsed in dishwashing liquid in tap water that have no apparent degradation. Still, I'm less inclined to take risks these days, especially since after so many years, I've convinced myself that the pictures I take now are worth more than the ones I took when I first started.
For about 15 years I wiped down my negatives with a cellulose sponge after the Photo-Flo dip. I quit doing that just because it seemed like a good way to wind up with particles rubbed into the emulsion.
Edwal LFN for me. Photo-Flo always left streaks on my negs. Don't know why. LFN leaves the film pristine.
It seems like anything that doesn't evaporate completely would leave some residue. That's one thing about liquid dish washing detergent. Anyone who's ever spilled that stuff can tell you it does not evaporate. It just slowly turns into a thick gummy crud. Maybe I should put some Photo-Flo in a dish and see if it evaoporates completely.
I've never tried Edwal LFN. I tried their "no-scratch" stuff on a marginally playable DVD once, though. I thought I was being so clever, but it didn't work, so I used their film cleaner to clean it off. Bad idea. It's no longer marginal.
I suspect that Photo Flo does not fully evaporate. However, if you use it as directed it will be sufficient to absorb into the emulsion and vanish when dry.
Photo Flo is mainly the nonionic surfactant called Triton X 100 and either propylene glycol (PF200) or ethylene glycol (PF600). The dilution ratios are different for these versions of Photo Flo, so if you mess up it will leave a residue.
I don't know the dynamics of negative washing. I'm pretty sure certain substances that are in my well water are not well absorbed by the gelatin, because when I get the surface water off I have no indication on the negatives that the water was anything but distilled. If there is any absorption into the emulsion of the calcium-magnesium compounds that make my water hard, I doubt that a surface rinse would remove it any more completely than a surface wipe. These wiped negatives have been kept for over 30 years with no sign of anything but film base, emulsion and silver. The only times I got any streaking were when I did NOT wipe the negatives. There was a time when I used a sponge squeegee, but found a soft clean cloth to be better. Old-fashioned cloth diapers are my current favorite.