Q. about brown tint on developed 70mm Aero Plus-X film

[Bogdan Karasek]

I just finished developing some 70mm Aero Plus-X. The film is used for aerial mapping, hence it is very sharp. I used the following procedure:

Presoak: 5min Water

Developer: Stand Developing: Rodinal 1:100, 60 minutes, 20 agitations for the first minute and then it stands.

Stop: 2 10sec rinses in water and then 2 minutes in water.

Fix: TF-2 ( an alkaline fixer)

Wash: 20 min

Photo-Flo: 30sec

When I dumped the soak water, It came out brown. With 120 film, water comes out blue/purple.

Is the brown tint normal?

Anybody have experience with this film?

Thanks!

[Jac@stafford.net]

Fix it again.

[Bogdan Karasek]

First thing that crossed my mind. I mixed a fresh batch of Fixer from scratch and inserted two short strips into the Fixer for 10 minutes.
No Change.

[ic-racer]

Isn't that only about 2.75 inches?

[Tracy Storer]

When I tried dilute Rodinol my usual film was not the usual color......not a lot of experience doing that, but I do seem to remember a browner, thinner neg than normal. Printed OK though. You could try selenium toning the neg as well for color and density remediation as needed.
And Yes, 70mm is not large format, but MY film was 5"x7".
: )

[Bogdan Karasek]

Isn't that only about 2.75 inches?

Yes, I cut off a piece from the 15 feet that I developed. Immersion in fresh hypo did not change anything..... the brown tint stayed

[Doremus Scudder]

Just for clarification:

Are you saying that the pre-soak water was colored brown after soaking the film (unlike other films that color the water blue/purple)? If so, then we're talking about the anti-halation coating on the film. There are many of these and they have many colors. I've experienced blue, purple, cyan, bright green and black. It could simply be that the anti-halation coating on your Aero Plus-X colors the water brown. If the film is fine, then don't worry.

If, however, you are implying that the film itself has a brown tint, then that's a different matter. That could be developer type, the emulsion itself, inadequate fixing (which I think you have ruled out), etc. If you're fixing 2x (I prefer 3x) the film clearing time in fresh enough fix, that's not going to change the emulsion color. Even fixing in exhausted fixer won't. Severe underfixing results in a fog of undissolved silver halides remaining in the film. This, however, usually looks milky, not brown.

If you are talking about the final water wash/rinse water (some call it soak, Germans call it Wässerung, etc. but it's the step after fixing), then you need to wash more. Colors in the wash water are usually dye couplers in the film (like the notorious pink in T-Max films) and often wash out more slowly. If this is what you are talking about, then wash more, until the water comes out clear. 20 minutes is enough for most films if the water is changed regularly (or running), but I like 30 minutes. Even then, some films still have a marked color cast (usually the T-Max films) and need a bit longer.

I believe you're talking about the pre-soak stage and the color of the water you pour out after the pre-soak. It that's the case and all your other processing steps are fine, then it is more than likely that this is just the color of the anti-halation dye for this film. How do the processed negatives look? Are they brown-tinted or not?

Best,

Doremus

[Bogdan Karasek]

hello Doremus,

138252138253

First off, the second attachement has two frames that I cut off a processed roll of 16 feet. The whole roll of film has that brownish tint. The first attachement is the front and back of snippet of unexposed Aero Plus-X

When I do a 60 minute stand development in Rodinal 1+100, I first soak the film for 5 minutes, and normally, if developing 120 format Tri_X or Efke, the water comes blue / purple. This time it was Brownish. Imagine my surprise when I took out the film for washing, constant flow of water for 20 minutes, and the film had that brownish tint which you see in the first attachment. The wash water was clear, no hint of brown..or any other color.

My first reaction was that the film had not cleared in the fixer, but close examination on the lightbox reveal images that are very sharp, great detail, and absolutely no fogging. I cut off the two images you see in the attachement and reinserted them into the fixer for 10 minutes.... I rigged it so that one image was in the fixer and the other outside. After 10min, no difference... wash for 20 minutes in running water, and again , no change.

Tomorrow, I'm going to print some of those tinted images and see the results. I have never used this film before, so it may well be that this is a normal thing. This film is used for aerial mapping, so maybe the brown tint is a normal part of the process. I will see what kind of prints I get


Anyway, Thank you for taking the time to address the issue.

Bogdan

[Tracy Storer]

That is very brown. I have shot 9.5" Aero Plus-X and it does not have that color, but is likely on a different base.

Have you tried the film in a different developing scheme, or being more direct, fixing some undeveloped film to see if the base has a color ? It may be the dilute Rodinol, or something about the film itself. Fixing undeveloped film will confirm or eliminate the latter.


hello Doremus,

138252138253

First off, the second attachement has two frames that I cut off a processed roll of 16 feet. The whole roll of film has that brownish tint. The first attachement is the front and back of snippet of unexposed Aero Plus-X

When I do a 60 minute stand development in Rodinal 1+100, I first soak the film for 5 minutes, and normally, if developing 120 format Tri_X or Efke, the water comes blue / purple. This time it was Brownish. Imagine my surprise when I took out the film for washing, constant flow of water for 20 minutes, and the film had that brownish tint which you see in the first attachment. The wash water was clear, no hint of brown..or any other color.

My first reaction was that the film had not cleared in the fixer, but close examination on the lightbox reveal images that are very sharp, great detail, and absolutely no fogging. I cut off the two images you see in the attachement and reinserted them into the fixer for 10 minutes.... I rigged it so that one image was in the fixer and the other outside. After 10min, no difference... wash for 20 minutes in running water, and again , no change.

Tomorrow, I'm going to print some of those tinted images and see the results. I have never used this film before, so it may well be that this is a normal thing. This film is used for aerial mapping, so maybe the brown tint is a normal part of the process. I will see what kind of prints I get


Anyway, Thank you for taking the time to address the issue.

Bogdan

[koraks]

I can't imagine Rodinal leaving the film base this brown. There would have to be something in the emulsion for the chemicals in the Rodinal to react with and produce this brown color, but then it would only be on the emulsion side of the film and as a result be quite faint. But I've never had this happen with any film and I virtually only use Rodinal. I suspect that this film just has a brown base for whatever reason; the color of the film base does remind me of color negative film, which comes in a variety of hues as well. Perhaps they just used a brown film base for reasons (I can't think of, though) related to further processing of the film. It may also have to do with the film being used for high-altitude applications, in which they may have tried to cut down the high degree of blue light in the spectrum and UV and blue reflection against the pressure plate by using a brown base.

All considered, given that you've fixed this extensively, I'd say that this is probably how it's intended to be.

[AtlantaTerry]

Isn't the important thing how the enlargements look? Does it matter what color the base is?

When I saw the photos of the samples, the first thing that came to mind was "color negative film". Is it at all possible that a mistake was made somewhere along the line and you ended up with color negative film instead of black and white?

What happens if someone tries to develop C-41 film in a B&W developer?

[koraks]

You get a normal negative, albeit rather thin and very grainy.

[Mark Sampson]

It's a while since I worked for Kodak and did lab work for their Aerial Systems people, but I will say I never saw anything like that. Might it be dichroic fog? Your processing method is far removed from what the film was designed for, but I don't think that's the whole answer. What is the 4-digit code for the film, and what is the expiration date? That information might help us figure that out.

[Bogdan Karasek]

Hello, If anyone is interested, this is an update on the developing of the Aero PluS-X. Yesterday, I shot a full 15 feet at 50asa, and decided to develop using HC 110 dil H (1:64) at 9:30min. I cut off about 2 feet and will develop that tomorrow in Rodinal 1:100 stand development 60min... which led to the initial fiasco. Curious to see the results. If stained redish brown like the first roll, then the fault is with the Rodinal.???????? Will keep posted. By the way, the film is superb, great detail, no wonder it was used for mapping.

[Harold_4074]

Koraks: Perhaps they just used a brown film base for reasons (I can't think of, though) related to further processing of the film.

As I understand it, when polyester started to replace acetate film base, it was found to be susceptible to "light piping" (distinct from halation, but comparably detrimental) so absorbers were put into the film base to suppress this. It is possible that this particular film was made with a film base that, for whatever reason, didn't become standard.

It is fortunate that the film doesn't have a rem-jet backing (carbon black in gelatin) to float off in the developer. I once developed some 35mm transparency film made for ballistic tracking cameras, and it was a real mess...

[Mark Sampson]

Your film base isn't brown by manufacture, for light-piping or any other reason. Try an acid stop bath and fixer (as I mentioned in the other thread). Rem-jet backing was used in motion-picture films, including Kodachrome, and i agree that it's a pain to deal with.