Kodak T-Max 400 processing problem

I am currently assisting with B&W photography and darkroom techniques taught to high school students. The first exposed film brought in for processing was a factory loaded Kodak T-Max 400 35mm roll. Right out of the cassette the film curved outward (counterclockwise) instead of the usual inward (clockwise) curl I've encountered in the past. It unraveled quickly off the spool and fought being loaded onto a tank reel. The resulting negatives consisted of a long black bar running the length of the film with a few gaps of faint latent imagery. Has anyone else encountered this problem? Was this roll loaded wrong at the factory? I normally use Ilford film so I'm wondering if the stiff, oddly curling T-Max roll is a normal characteristic and something I and the students are going to encounter with future incoming exposed rolls.

The long black bar is due to improper loading of the exposed film onto the reel. The film touched and this contact prevented the film from being wet by the developer.

 

I have seen a few camera models that roll the film emulsion side out on the take-up spool. Mostly these are one-shot party cameras. However, I have seen one or two high-end cameras that work this way also. The spooled film tends to take a reverse "set" after a time in storage.

 

As you know, film consists of multiple layers. Each has a different coefficient of expansion and contraction (like a bi-metallic bar element is an aneroid thermometer). So film also has the tendency to curl. The direction of curl is away from the layer with the greatest expansion. To mitigate, all films have a "balance" coat on the reverse to counter any negative curl tendency. Sometimes, adverse conditions of storage will interfere and we get a negative curl. Film is hydroscopic so it takes on water from the air. Subject film to high humidity and bad things happen! In my 55+ years in the photofinishing business, technical manager for 7 labs each sized for 20,000 rolls a day, I have seen most everything!

I have seen a few camera models that roll the film emulsion side out on the take-up spool. Mostly these are one-shot party cameras. However, I have seen one or two high-end cameras that work this way also. The spooled film tends to take a reverse "set" after a time in storage.

 

Quite a few high end cameras wind "emulsion out." On Leicas, I know at least screw mounts load this way. Virtually all manual advance Nikons do, as do some Canon SLRs(the F-1 series).

Plastic reels or stainless?

The long black bar is due to improper loading of the exposed film onto the reel. The film touched and this contact prevented the film from being wet by the developer.

 

I have seen a few camera models that roll the film emulsion side out on the take-up spool. Mostly these are one-shot party cameras. However, I have seen one or two high-end cameras that work this way also. The spooled film tends to take a reverse "set" after a time in storage.

 

As you know, film consists of multiple layers. Each has a different coefficient of expansion and contraction (like a bi-metallic bar element is an aneroid thermometer). So film also has the tendency to curl. The direction of curl is away from the layer with the greatest expansion. To mitigate, all films have a "balance" coat on the reverse to counter any negative curl tendency. Sometimes, adverse conditions of storage will interfere and we get a negative curl. Film is hydroscopic so it takes on water from the air. Subject film to high humidity and bad things happen! In my 55+ years in the photofinishing business, technical manager for 7 labs each sized for 20,000 rolls a day, I have seen most everything!

Every Pentax 35 mm camera I have seen (manual advance) winds the emulsion side out on the take up spool--a camera repair tech once explained to me that it saved an extra gear in the film advance mechanism of manual advance cameras. although I have no idea if that's true.

I always though the emulsion out was to partly counter the curl that the film originally had in the cassette.

 

Leica, Leica descendants such as Canon rangefinders, and I believe most Nikons, spool emulsion side out.

 

And yes the leader tends to get this curve, probably more if it is in the camera longer.

The long black bar is due to improper loading of the exposed film onto the reel. The film touched and this contact prevented the film from being wet by the developer.

 

I have seen a few camera models that roll the film emulsion side out on the take-up spool. Mostly these are one-shot party cameras. However, I have seen one or two high-end cameras that work this way also. The spooled film tends to take a reverse "set" after a time in storage.

 

As you know, film consists of multiple layers. Each has a different coefficient of expansion and contraction (like a bi-metallic bar element is an aneroid thermometer). So film also has the tendency to curl. The direction of curl is away from the layer with the greatest expansion. To mitigate, all films have a "balance" coat on the reverse to counter any negative curl tendency. Sometimes, adverse conditions of storage will interfere and we get a negative curl. Film is hydroscopic so it takes on water from the air. Subject film to high humidity and bad things happen! In my 55+ years in the photofinishing business, technical manager for 7 labs each sized for 20,000 rolls a day, I have seen most everything!

 

Thank you for your response, Alan Marcus! I've encountered a dull black/gray bar from improper tank loading before. I found examples of this while clearing out and restoring the school's darkroom. Is a shiny black bar the characteristic of this problem with current T-Max film? I'm working with a variety of older film cameras found in the school's resurrected darkroom. I tested each camera with my go-to Ilford film and processed the rolls in my home darkroom with good results. I brought this same tank to school for the student's use. Since we are located in Wisconsin, the students have endured extreme weather. Perhaps this was a factor as well. Yet, I loaned by Canon F1 loaded with Ilford HP5 to a student which, when returned. had been left in a car overnight during sub freezing temperatures. This did not affect the resulting negatives. The T-Max rolls are newly purchased and the turn-around shooting time from the student was a maximum of 3 days. I'm wondering if it would it be better to ask the school to stock Ilford film?

Plastic reels or stainless?

Hi, Joel. Until this semester the school's darkroom hasn't been in use for over a decade. The stainless steel reels discovered in the room looked as if they had been dropped at one time or another so I was reluctant to use them. I brought in the plastic reel tank I had used in my home darkroom to test the school's cameras. The tests were conducted with Ilford HP-5 film and each test came out normal. I loaded the camera for the student according to the manual found on-line.

"I'm wondering if it would it be better to ask the school to stock Ilford film?"

 

Whether T-Max or HP5, they should be ok. The black bar sounds like a handling problem. Try the T-Max again under the same conditions that the HP5 was exposed and processed under

"I'm wondering if it would it be better to ask the school to stock Ilford film?"

 

Whether T-Max or HP5, they should be ok. The black bar sounds like a handling problem. Try the T-Max again under the same conditions that the HP5 was exposed and processed under

Thank you for your suggestion! Since I first posted, I have developed another student roll of T-Max 400 using the same equipment and technique as the first with the only difference being it was shot with the school's Vivtar camera instead of the Nikon N65. This second roll of T-Max loaded perfectly on the tank reel and negatives are normal.

There are some differences in the problem loading plastic and metal reels.

 

One is that if they are even a tiny bit damp, the film sticks to plastic reels and won't slide in.

 

When you force it, it can go out of the track, and touch nearby film, which causes it not to

develop, and usually also not to get fixed. If you look at the negative, it will have the color

of undeveloped film (which is what it is).

 

This is the most common failure in loading either plastic or metal reels.

 

Otherwise, old cameras can have light leaks, which will cause black areas on the negative,

and white areas on the print. This can also happen outside the camera, for instance too much

light on the outside of a 35mm cartridge. (The light trap isn't perfect.)

A long time ago, when I had a similar issue (film in camera curling wrong way), I 'cured' it by taping two films 'back to back' and loading both in the plastic Paterson reel, then giving 10% extra dev. Worked quite well, and the films seemed to dry flatter.

 

HTH

If the film came out of the cassette curling the wrong way, the user may have just rewound the film the wrong way, i. e., counterclockwise.