Twisty Film: Bad Developing?

[RattyMouse]

I'm just wondering, if I see film that when hanging to dry twists in one direction rather than hang flat, is that a sign of something done wrong?

Thanks!

 

[markbarendt]

No.

 

[Sirius Glass]

No but raising the humidity might help.

 

[Tom1956]

It always twists up and looks lumpy till it dries, then straightens right out. Unless it was HIE135-20 which stayed curly no matter what.

 

[Regular Rod]

Some films are quite awkward in this regard. Others, like ILFORD films, never seem to have a problem...

RR

 

[rjbuzzclick]

If you're not doing it already, a clothespin or two clipped to the lower end of the film will help it hang straight while drying.

 

[Sirius Glass]

+1

 

[RattyMouse]

If you're not doing it already, a clothespin or two clipped to the lower end of the film will help it hang straight while drying.

Yep, already do this. I'm surprised at how little this helps. That film has some serious torque to it!

 

[tron_]

I use those black binder clips. One big one (1 inch) on each side of the film. Never have a problem with film curling anymore.

 

[RattyMouse]

Curling i have no problems with. It's twisting that seems endemic to my film.

 

[37th Exposure]

Curling i have no problems with. It's twisting that seems endemic to my film.

Does it straighten out as it dries? What brand is it? Are the weights applied evenly on both ends? I have never seen film not straighten out as it dries as long as it is weighted evenly, in twenty some odd years of darkroom work. Some of the old ORWO 120 films did curl up horribly no matter what. I won't be buying anymore Kodak film, not that there is anything wrong with it. It is the only brand I use today that just won't dry flat and that annoys the heck out of me because it bounces around on my undersized portable lightbox and puffs up the plastic sleeves way out. Its the only brand that cups itself. I save a lot of aggravation simply by using only Ilford and Kentmere. Foma dries even flatter, but I still don't trust their QC.

 

[RattyMouse]

Does it straighten out as it dries? What brand is it? Are the weights applied evenly on both ends? I have never seen film not straighten out as it dries as long as it is weighted evenly, in twenty some odd years of darkroom work. Some of the old ORWO 120 films did curl up horribly no matter what. I won't be buying anymore Kodak film, not that there is anything wrong with it. It is the only brand I use today that just won't dry flat and that annoys the heck out of me because it bounces around on my undersized portable lightbox and puffs up the plastic sleeves way out. Its the only brand that cups itself. I save a lot of aggravation simply by using only Ilford and Kentmere. Foma dries even flatter, but I still don't trust their QC.

Ilford Delta 3200, Kodak Tri-X, and Fujifilm Acros 100 all do it. I am going to develop some HP5 in the near future. No, drying does not help reduce the twisting.

Again, curling is not the problem, twisting is. My film looks like the threads on a screw. The film does not want to curl up into a roll.

 

[37th Exposure]

Now that really is something if it's like a screw! It does not look like anyone else in this thread has seen it. You might ask the film companies.

 

[MattKing]

Curling and twisting are due to the emulsion drying at a different rate than the substrate material. For most top-line films, that is due to a problem with drying temperature and/or humidity.

I used to have that problem when I needed to use a hot air dryer to get quick results (newspaper work). I've never had the problem with Kodak or Ilford film when I dried it at room temperature, in moderate humidity.

What are the conditions like where you dry the film?

 

[RattyMouse]

Curling and twisting are due to the emulsion drying at a different rate than the substrate material. For most top-line films, that is due to a problem with drying temperature and/or humidity.

I used to have that problem when I needed to use a hot air dryer to get quick results (newspaper work). I've never had the problem with Kodak or Ilford film when I dried it at room temperature, in moderate humidity.

What are the conditions like where you dry the film?

I'm in Shanghai where there is natural high humidity. Further, to reduce dust on the film I fire up the hot water in my shower (I develop in my bathroom) for a few minutes and fog up the windows with humidity. I get no dust marks on my film.

 

[MattKing]

I'm in Shanghai where there is natural high humidity. Further, to reduce dust on the film I fire up the hot water in my shower (I develop in my bathroom) for a few minutes and fog up the windows with humidity. I get no dust marks on my film.

Can you use room temperature water in the shower instead? What is the air temperature where you dry the film?

EDIT: our humidity here in temperate rain forest south-west British Columbia is moderately high as well, but the temperature is almost always near 20C

 

[RattyMouse]

Can you use room temperature water in the shower instead? What is the air temperature where you dry the film?

EDIT: our humidity here in temperate rain forest south-west British Columbia is moderately high as well, but the temperature is almost always near 20C

Yep, I can try that next time. It is not terribly warm here in Shanghai now so after the warmth of the shower blast is gone the air temp is probably 20 C or so. I close the door so the humidity stays high.

Thanks for the suggestions.

 

[markbarendt]

Ratty can you use a coat hanger or rod to keep the bottom from twisting

 

[MattKing]

If your humidity is already high, you may not want to increase it more. The blast from the shower and closing the door will help with the dust, but slow drying in moderate humidity and temperature is usually the best solution.

 

[RattyMouse]

If your humidity is already high, you may not want to increase it more. The blast from the shower and closing the door will help with the dust, but slow drying in moderate humidity and temperature is usually the best solution.

I will give that a shot and see how it goes.

Thanks!