drying marks on Agfapan 25

I use the same process with TMAX 100 and Agfapan 25 film -- but with the Agfa I get differential drying marks and with TMAX I don't. Can anyone suggest how to avoid the drying marks? Here's how I process....

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After fixing: 1 min. water bath, 3 mins. Hypoclear, 15 mins. water bath, 30 secs. PhotoFlo(I've tried varying dilutions) in distilled water (I've also dried Edwal LFN with the same results). Snap water from film and hang to dry.

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After most of the water has evaporated from the film, there are still droplets of water on the emulsion side of the film. These drops cause differential swelling of the emulsion, which results in dimpled spots on the film. They print as white-bounded amoeba-shaped spots with a dark spot in the center.

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I don't have to squeege or sponge my TMAX film, and would prefer not to do so with the Agfa -- but at this point I see no alternative.

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Agfa tech support was not very helpful.

Peter, It sounds like the classical air bell problem. The older

emulsions where prone to this if you didn't rap the tank hard to

dislodge the air bubbles from the film when you put it in the

developer. If this isn't the case, I would run the film through the

developing stage and do another quick fix and Perma wash again. This

will not do anything to the film other than soften the emulsion and

"usually" clear up the anomilies.

Hope this helps,

Cheers

Scott, thanks for the reply. These are not air bells -- I've dealt

with them before and know what they look like and how to avoid them.

I use several drops of Edwal LFN in the developer to reduce surface

tension, and I rap the tank sharply after pouring in the developer,

and after each agitation.

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These marks are shaped differently than airbell marks. These tend to

be elongated rather than round and have a distinct white boundary

with a dark dimple in the middle -- airbell marks are round shapes

with a soft border. Yes, I can re-wash the film, which softens and

swells the emulsion, but the drying marks just occur again, in a

different location.

Peter, I have developed several dozen rolls of Agfapan APX 25 film and treated with Kodak Photoflo

there is no drying mark.

The drying marks on your film may be caused by TOO MUCH Photoflo.

I use only 6 drops of Photoflo in 250 cc distilled water, dip one minute and hang up to dry

When you say you "snap the film" to get rid of water, I get worried.

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The purpose of LFN and Photoflo is to reduce surface tension, that is

to get the water to sheet off instead of form drops. Better to have a

throughly wet surface and have it all flow to the bottom, than drops

form, which may dry in place, leaving marks.

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1. Use distilled water for your Photoflo/LFN solution.

2. Don't snap the film, let it all run off.

3. If you have the film horizontal rather than vertical, the water

flow has a shorter distance to the bottom of the film, so it does it

faster, and dries faster.

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If you get an accumulation of water at the edge of the film, you can

run a small towel ON THE EDGE ONLY to reduce its accumulation. You

may have to do this several times. I do this with sheet film, but

only at the corner, as I hang it by one corner.

Charlie, by "snap", I mean that when the 120 film is still on the

developing reel, I hold the reel in one hand and snap my arm/wrist

downward to expel the water out the side of the spiral. This seems a

safe way to remove excess water before unspooling the film and

hanging it to dry. The Agfa technician I spoke with also mentions

that film development machines will mechanically snap a vertically

hanging film by bouncing the clip which holds the top end of the

strip (the bottom end of the film has a clip with a weight on it.) He

suggested I do this also, but I have not tried it, and in fact the

weights I currently use will probably slip off the bottom end if I

bounce the film. I could try bending over the bottom 1/4" of the

film, and using a proper film clip with a good grip -- but frankly I

don't think this effort will help much.

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I like your idea of hanging the film horizontally to dry, so that the

long edges of the 120 film are at the top and bottom. The engineering

of how to suspend the film in this position long enough to dry it is

an interesting problem..... I imagine some strings and rubber bands

at the proper tension would hold the film just taught enough.... Of

course, I also need to rig horizontally-opposed anchors to which I

can attach the film/rubber-band/string arrangement.

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Thanks for your suggestion.

Martin, thanks for your reply.

According to Kodak's tech support, the symptom of too much PhotoFlow

is a residual scum on the film -- which I do not have. The

differential drying marks which I am getting are, according to Kokak

and Agfa, a classic symptom of too little PhotoFlow or LFN. However,

I have increased the concentration of PhotoFlow up to 3 times Kodak's

recommendation, but I still get the marks -- which are the result of

differential rates of drying for the contiguous areas of film (the

wet film is swollen, as it dries it reduces -- but because there are

wet spots surrounded by dry areas on the emulsion side of the film,

the reduction is differential.)

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If you hold the emulsion-side of the film against the light just

right, you can see the "step" which is the edge of the drying mark --

the drying mark is togographically different than the adjacent film,

and prints as a white outline. On the non-emulsion side of the film,

there is a small indentation or dimple, where the substrate is

buckled due to the stress caused by differetial drying of the

emulsion.

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What's curious to me is that I do not have this problem with TMAX --

only with Agfa. I asked Agfa what might cause the difference -- they

pointed out that the emulsion layer of Agfa film is thicker than that

of Kodak, but did not understand how that might contribute to these

drying marks.

After doing your 'flick' (which is how I do it too) and unspool the

film, are there still droplets on the film, or is it evenly wet?

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I have noticed different film's curl substantially more than others

during the drying phase. Konica IR is one that really curl's before

straighting out when dry.

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what is the temperature/humidity of the room you dry the film in?

could this be a factor? Maybe it's to hot and it's drying to quickly,

or the reverse (I don't know, just a suggestion)

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My 120 APX-25 drys beautifully with a distilled water rinse

containing a few drops of Ilford wetting agent. I leave it in this

for 1-2mins, do your 'sideways spool flick', then hang it in the

shower. The room temp is anywhere from about 18C up to 25C.

Just wait a while and the drying marks will disappear along with all

Agfapan 25!

Nigel, my drying temperatures are in the same range as yours, and

humidity is consistently low. I would suspect that consistently high

humidity might retard drying and somehow contribute to my problem,

but I can't imagine that low humidity such as I have would be a

problem. I have not used heating or air condidtioning in my home

during the last 6 months, which is when I've been having the problem.

I dry film in my bathroom, but always at least 3 hours after using

the shower (i.e., I let the room dry out before processing film). I

run the room's small exhaust fan while the film is drying.

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When the film initially comes off the spool, the water is sheeting

evenly.

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There is a bit of curl of this film while drying, but I don't

remember if it is more or less than with TMAX100 -- and the curl does

not seem to be related to the drying marks.

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I could try Ilford's wetting agent, though I have already tried with

no success both a sudsing type (PhotoFlow) and a non-sudsing type

(Edwal LFN).

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Yes Sal, I realize the problem will go away when Agfa 25 does -- but

I have a freezer full of the stuff which I'd like to use.

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I'm going to develop some more Agfa 25 this weekend. I may try

holding it in a horizonal position (edges up and down) until it

dries -- see if that helps.

Peter, probably no point buying another bottle of wetting agent since

many people use the 2 you've tried with success.

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Maybe if you can 'hang' up the film sideways and you still get the

marks, examining them closely (shape) and comparing to ones that

occured when hanging the film vertically, might confirm that it is

drying marks or something completely different... It's a bit of a

mystery! Let us know how your test goes.

I started developing Agfapan 25 at home because drying marks were

produced by commercial development. This film has to be the most

sensitive to drying technique I have used.

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Have you tried it with forced air of some kind, even just a little

fan? I used my shower with the window open, so I had a tiny amount

of airflow. What about running your shower fan when you hang the

film in there?

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I have used both Photoflo and LFN at recommended mixtures and have

not had these problems, but my drying environment does contain just a

little air flow.

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What about using compressed air on your film? When you hang it up,

use compressed CO2 to whisk the excess water from the film.

Hi Brian -- I do run my bathroom's exhaust fan while drying the film.

Just last night I developed 3 more rolls -- this time I held the film

horizontally and wiped excess off the bottom edge as water ran down

there. Still, I ended up with numerous drying marks -- the water just

does not sheet properly, it beads up. I even tried a concentration of

LFN which is 4 times greater than Edwal recommends, with the same

result.

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Your suggestion of forced air is a good one, it might help. However,

to force all the water off 3 rolls of 120 film (this is one batch for

me) would take a lot of air -- so if it does work I suspect it would

be quite expensive to buy all that canned air.

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I'm pretty much resolved to using a sponge squeegee (I've tried a

rubber-bladed squeegee but it is not very effective -- I get lots of

chatter of the blades, and I have to use a lot of pressure and it

still leaves droplets on the film. I've used a sponge squeegee in the

past with success.)

I've had lots of similar problems with APX-25. At the suggestion of

the local Agfa dealer, I started leaving it in the photoflo for 2

minutes instead of 30 seconds. This helped alot

I have never had this problem with APX 25 or with other films. I use

only one or two drops of wetting agent with my tap-water (great water

here in northern Sweden) and dip the film for 30 sec to one minute.

Peter,

I, too, have had problems with differential drying marks with Agfapan

25. I rinse for 60 seconds in a bath of distilled water and PhotoFlo

200 (I have always used PhotoFlo at about 1/2 strength). I have

never had the problem with any other film, and have been developing

B&W for over 20 years. I recently took a trip to Glacier National

Park, and was unable to use many of the images because of drying

marks. I have since switched back to Ilford Pan F 50 developed in

D76 1+1. I like the lack of grain and tonality of Agfa 25, but what

is the point if you can not be assured of a sparkling negative after

drying? I know this doesn't help you out, but there are others with

the same experience.

Mark, thanks for your reply -- the word from you and a couple of

others is a bit of a relief, to know that I am not the only one with

this persistant problem. In fact, I suspect that drying marks on

Agfapan 25 are a lot more common that many suspect -- because they

are not particularly evident where there is a lot of image texture. I

am currently shooting outdoors and often use a lot of cloudless sky

in my images -- the perfect stage for processing gremlins.

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One way to tell whether the marks exist, even with a highly textured

image, is to look for the deformation of the film base. You have

probably seen these, Mark -- if you look at the non-emulsion side of

dry, processed Agfapan 25, you will see shallow indentations of the

film base. That is, the film is not perfectly flat but has slight,

gradual indentations. These are the sites of the drying marks.

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Apx25 film base feels to me much flimsier, less stiff than that of

Tmax 100 -- which I imagine might contribute to this problem. I asked

Agfa if their film base was thinner or less rigid than that of Kodak,

but I got a non-answer.

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I bought sponge tongs and have begun wiping all of my Agfa film dry.

I usually wipe off drying marks on my dry HP5 negatives with fine

microfiber cloth. Not sure if Agfapan 25 is too delicate for this.

Anyway, try it on one not too important frame.

Based on a suggestion I picked up on one of the photo mailing lists

(can't remember which one) I've begun adding a jigger of rubbing

alcohol to my final rinse (distilled water and about half the

recommended Photo Flo.) I don't use Agfa 25, but have noticed

fewer water spots on my other film since adding the alcohol. It

doesn't cost much to try this, if it sounds interesting to you.