Roll of film fades to black

[steveb533]

Hi,
I just developed two rolls of 120 film. On both rolls the last frames look correctly developed but then they get progressively darker, to almost black on the first frame (closest to the middle of the reel). I think this is probably the developer being exhausted? I'm going to make a new batch but thought Id double check in case someone thought it could be something else. thanks,

Steve

 

[Bob-D659]

Type of tank? Did you install the black light trap tube in the reel?

 

[Worker 11811]

What kind of developing tank did you use? A plastic, "Patterson style" tank?

Did you remember to put the center tube in the tank? Reason being, if you don't put in the center tube, light can get in and spoil your film.
I'm not saying that this is what you did but, given your description of the problem, it fits.

Don't feel embarrassed. It's a silly mistake but it's a mistake that almost everybody makes once.
Yes, I did it once. Ever since then, even though it was years and years ago, I swore I'd never do that again so I still check my developing tank every time to make sure I put in the tube.

That way I have more time to make other stupid mistakes.

 

[polyglot]

Are just the frames black (and by black, do you mean more-dense?) or are the gaps between the exposures (which should be completely clear!) also going dark?

If the gaps (rebate) are going dark, you have a light-leak. Would be more typical to see one side of the roll dark instead of one end, but whatever. Depends on the leak. Definitely you need to include the centre-core for your tank if it has one. The rubber caps on Paterson tanks that keep the liquid in while agitating are nowhere near lightproof; light-tightness depends on the funnel fitting properly into the centre-core, which fits into a notch in the bottom of the tank.

If the frames are denser at one end of the roll but there's no fogging, you have either a metering issue or mechanical issue like sticking aperture that's causing overexposure as you go, or you have an agitation issue that means that one end of the film is being developed properly and the other is not. Perhaps you did rotary development with insufficient developer, only the outer part of the roll was developed properly and the inner part only got the occasional splash of chemistry.

Important question (for the it's-not-fog case): do you see a variation in the density of the rebate markings along the length of the film? If so, it's a development (probably agitation or coverage) issue). If they're constant, you probably have an exposure issue. Can you post a digital photo (e.g. phone-cam) of the roll in question?

 

[albada]

It's a silly mistake but it's a mistake that almost everybody makes once.

Users of stainless steel tanks don't make that mistake. But the tops of SS tanks don't fit tightly, and if one doesn't hold it correctly when inverting... the result is worse than forgetting that plastic tube.

Mark Overton

 

[steveb533]

Thanks for the replies! It is a plastic patterson style tank. Yeah I did forget to put the center tube in, now that I think of it. That sounds like what happened. Thanks,
Steve

 

[Worker 11811]

Users of stainless steel tanks don't make that mistake. But the tops of SS tanks don't fit tightly, and if one doesn't hold it correctly when inverting... the result is worse than forgetting that plastic tube.

Mark Overton

Maybe you don't make that mistake but that just gives you the opportunity to make all sorts of other great mistakes!

I have steel tanks too. When it's really important, I put a lap of electrical tape around the top. That leaves me more time for my favorite mistake. When I get distracted talking to somebody and I forget whether I just agitated my film at the top of the last minute or if I'm just about to agitate at the top of the next minute.

Yes, I know, it should be a trivial thing to remember but I've got a touch of A.D.D. and every once in a while... Ooh, shiny!
I just have to expend a little more effort to keep my mind on my work than most people do. The trick I use to prevent that is to set my tank down in a different corner of the sink each time.

Start off setting it down in the top-left corner of the sink. On the each successive round, put it in the top-right, bottom-right, bottom-left, etc.
I might make myself seem like a retard when I explain it but this is what I have to do in order to prevent mistakes.

Using a digital, countdown timer that beeps when it's done also helps keep my mind focused.