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smeylan
2-Jan-2021, 21:57
I keep getting big splotches on the edges of my negatives -- it seems to be the bottom of the negative where water pools in the drying process. I am just air drying on a clip after a 15 minute water-only rinse in an SP-445. What can I do to avoid this? Also why is it leaving a mark if it's just water?

Here's an example in the top right corner (I also messed something up with the DoF on the left side, I know!)

211109
211110


bigger version here:
https://www.dropbox.com/s/ltaez078q6e5kws/DSC_1804.jpg?dl=0

Willie
2-Jan-2021, 23:08
"Just water" has dissolved minerals and impurities.
Try last two soaks in distilled water with last using Kodak Foto Flo or Ilford Ilfotol Wetting Agent or similar.

Then hang to dry in clean area with no dust floating in the air. A good way to do this is your bathroom. Run the shower hot for a minute or two to steam up the air. Then hang the negatives to dry, close the door and don't go back in until they are dry. A couple hours should do it.

Clean negatives.

jim_jm
2-Jan-2021, 23:14
Use PhotoFlo or other wetting agent mixed with distilled water, not tap. Mix according to the instructions on the bottle, which for PhotoFlo is usually 1+200, very dilute.
After your final wash in tap water, immerse the reel/roll/sheet in the wetting agent for about 30 sec (don't stir or agitate), then hang to dry. There should be no need to wipe or squeegee the film at all.
Some folks will state that they don't use wetting agent, or that they mix with tap water and have never had any problem. I don't doubt that, but everybody's water quality is different.
The spots are usually caused by minerals or other dissolved particles in your tap water that will leave residue on your film after drying.

koraks
3-Jan-2021, 04:20
I always hang the film from a corner using a clip and also attach a clip to the bottom corner. That helps the water to drip from the film. Remove the bottom clip after a few minutes when all water has drifted away.
As said above: photoflo and/or distilled water help.

Ironage
3-Jan-2021, 04:34
Looks more like a developer problem than a drying problem. The whole sheet looks unevenly developed.

Tin Can
3-Jan-2021, 05:55
I stopped using dish soap or Kodak Photo-Flo 200 Solution (16 oz) (https://www.bhphotovideo.com/c/product/28195-REG/Kodak_1464510_Photo_Flo_200_Solution.html?gclid=Cj0KCQiA88X_BRDUARIsACVMYD9wAJqMhJyx9M1CG297gKx7s7LXHhm3iu2ZPD09lpMHoAg1iMsf_s0aAq0ZEALw_wcB) in last wash after I installed a Hass Temp control with hot and cold filters which flows all water in DR

I hang as others say, by corner clip, then use a paper towel to just touch the bottom drips a couple times during cleanup

Then I alway dry overnight with no fans running over DR sink and don't peek or check drying

I scan all right away in morning, just as reference

A few get wet printed, some get archival envelopes, not many

Every expert here, I am not one, always says 'TEST EVERYTHING YOURSELF!'

ic-racer
3-Jan-2021, 07:58
Not sure what I'm seeing when I download the Jpg. Comes up as a transparency. If it indeed is a negative, the only excess density that might come from water impurity would be the tiny spec in the lower right. Is this the issue?

jtomasella
3-Jan-2021, 09:24
The last rinse on my 4x5 negatives I use the top off water for my reef tank (reverse osmosis water) and photo flow. I also dab the drip on the end with a paper towel until it stops pooling.

smeylan
3-Jan-2021, 11:05
@ic-racer It's a positive from my away-from-home "scanning" system -- 500mm on a full- frame DSLR pointed at a monitor. The main thing I am worried about is the dark spot in the top right corner (see the 2nd inline image).

@Ironage The particular dark spot in question was not there when I inspected the negative before drying, and it was exactly where some water pooled on the negative. That said, it does seem like the sheet is unevenly developed -- the left 1/3 seems underdeveloped. I am not sure what to do about this besides agitate my dev tank more (it's also possible that it is differences in brightness in my monitor — I will test that). Also there was a graduated ND filter (top to bottom) that I think is a bit too strong.

Next time I will try distilled water, Photo Flo, putting a clip on the bottom corner, and a paper towel to slurp up any pools. Thanks all!

Doremus Scudder
3-Jan-2021, 13:11
... @Ironage The particular dark spot in question was not there when I inspected the negative before drying, and it was exactly where some water pooled on the negative. ... Next time I will try distilled water, Photo Flo, putting a clip on the bottom corner, and a paper towel to slurp up any pools. Thanks all!

Water pooling is bad. That's why wetting agents were developed and employed. Not only could your tap water contain impurities, but the difference in drying rate from areas with water pooling vs. drier areas can stretch the emulsion and cause rings and splotches.

Best practice (for good reason) is a final rinse in distilled water with a wetting agent mixed to recommended or slightly weaker dilution. If your tap water is hard, extend the final rinse to a soak of several minutes to help leach minerals out of the emulsion. (Note: you can get by with a slightly weaker dilution if your tap water is soft and if the water on the negatives sheets nicely and forms no droplets or pooling whatsoever. If in doubt, use a bit stronger dilution.)

Use your distilled water/wetting agent solution one session. It doesn't keep well and grows bacterial slime rather quickly.

To squeegee or not to squeegee film is your choice. I do, between two clean and soft fingers dipped in the wetting agent solution. Hang to dry so the water drains to one corner. With roll films a weighted clip on the bottom end is a must. Then, as the water collects at the corner, drain it away with a touch of a finger or a paper towel.

Result: no more splotches.

Best,

Doremus