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Processing Issue or Light Leak?


ralf_j.

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Looks like a processing fault from inadequate agitation. Classic 'streamers' from the sprocket holes. Could also be due to inadequate fixing.

 

However, it's difficult to be certain from a frame-only scan. If there's also fogging outside of the frame area it might be a light leak.

 

It's very grainy. What film was it? And how was it developed?

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Hi -

 

Thanks for responding. Some more details which have me even more puzzled: this film was a Kentmere 400 which expired some time in late 2015 but it has been cold stored. I processed this in the same tank with a roll of Mitsubishi Gekko MW 100 Plus (AKA Maco UP100) in Rodinal 1:25 for ~ 7minutes and 50 seconds at 20C since the timings were almost identical. The Gekko (expired) film has also been frozen but the results from it are much better than the Kentmere (I am in the process of scanning it now) I see no bands like these so I am close to ruling out potential leaks. Agitation was the same for both films obviously since they were in the same tank, 30 secs the first min, and 8 inversion every remaining minute. I fixed it Kodak Rapid fixer with hardener for about 4 minutes.

 

I am not sure if the Maco film chemistry negatively impacted the Kentmere emulsion? I also am noticing some faint yellowing or light brownish stains in the emulsion (not sure where that is from) however since this is B&W film, no real harm done.

 

I washed for 10 minutes and rinsed with photo-flo. Still puzzled with Kentmere's results as I have had better luck with it in the past. Also the contrast of negatives was very low and you can see that the negatives are muddy and not sharp even though there was decent light when some of the shots were taken. Grain is expected to be higher with 400 iso film, but this was way too high. Too many variable smh!

 

Thanks again for your thoughts and any future ideas.

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I am wondering about underfixing, but the same effect as above.

 

Though usual would be agitate every 30s.

 

The usual effect is that development products, with higher density than water,

move down in the solution. Without enough agitation, they slow down

development non-uniformly. Though since the sprocket region is usually

not exposed, it shouldn't be developing much.

 

During fixing, fixer products (silver thiosulfate complex) can also slowly move

down, and slow down fixing. And since the regions between sprockets

are not exposed, they do generate fixer products.

 

Your note about brown is another indicator of underfixing.

 

And you don't mention agitation during fixing.

 

Normally, one should fix enough that this isn't a problem.

 

Four minutes sounds about right for non-hardening, but hardening

slows down the diffusion of fixer into, and complex out, of the emulsion.

 

In any case, refixing isn't hard and might help.

-- glen

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4 minutes fixing? Not long enough!

 

The brownish stain makes me suspect underfixing. Different films take different fixing times.

 

Stick the film back in the fixer for at least 10 minutes and see if the streaks disappear.

 

I don't care if fixer calls itself 'rapid' or not. Since you can't over-fix a film, I'd give at least 6 to 8 minutes (depending on prior use) fixing in future.

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I am wondering about underfixing, but the same effect as above.

 

Though usual would be agitate every 30s.

 

The usual effect is that development products, with higher density than water,

move down in the solution. Without enough agitation, they slow down

development non-uniformly. Though since the sprocket region is usually

not exposed, it shouldn't be developing much.

 

During fixing, fixer products (silver thiosulfate complex) can also slowly move

down, and slow down fixing. And since the regions between sprockets

are not exposed, they do generate fixer products.

 

Your note about brown is another indicator of underfixing.

 

And you don't mention agitation during fixing.

 

Normally, one should fix enough that this isn't a problem.

 

Four minutes sounds about right for non-hardening, but hardening

slows down the diffusion of fixer into, and complex out, of the emulsion.

 

In any case, refixing isn't hard and might help.

Thanks ralf. The image posted first, with sprocket marks, which frame number is it on the roll? Closer to #1, or closer to #36?

It was in most of the frames on this roll.

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The fixer I used was indeed the Kodak Rapid fixer which says 2-4 minutes in the instructions. I guess that isn’t enough?

 

I use Ilford Rapid Fixer, and not Kodak. The Ilford fixer doesn't come with the hardener.

 

(Most now are hard enough.)

 

Also Kodak Rapid Fixer is used diluted 1:3, where Ilford is 1:4.

I presume you used 1:3.

 

The times are for freshly mixed, and otherwise optimal conditions, and also,

as well as I know, without added hardener.

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-- glen

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I use Ilford Rapid Fixer, and not Kodak. The Ilford fixer doesn't come with the hardener.

 

(Most now are hard enough.)

 

Also Kodak Rapid Fixer is used diluted 1:3, where Ilford is 1:4.

I presume you used 1:3.

 

The times are for freshly mixed, and otherwise optimal conditions, and also,

as well as I know, without added hardener.

I see, this definitely has been used many times, i will extend the time next processing.

Edited by ralf_j.
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Kodak gives a capacity of 32 rolls (135-36 or 120) per liter for diluted rapid fixer:

 

http://imaging.kodakalaris.com/sites/prod/files/files/product-categories/e103cf.pdf

 

Ilford says 24 rolls per liter for theirs:

 

https://www.ilfordphoto.com/amfile/file/download/file/1833/product/711/

 

(The difference just about matches the different dilution for the two fixers.)

 

I normally mix up 500ml for film strength. I try not to use it for more than a year,

(probably way beyond recommendation) before mixing more.

 

It is supposed to stay within a pH range. Carry-over developer, especially with

water for stop bath (recommended for Diafine), can increase the pH.

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-- glen

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I am not wealthy, but i realize that can be a relative term.

Fixing is so important, especially with Negatives. You can always Print another Pulitzer Prize winning photo. :)

Anyway........I usually do not develop more than 2-4 rolls at one time. Unless i know i am going to re-use the fix in a few days, i dump it in the bucket.

It is not all that expensive.

Good Luck

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  • 2 weeks later...

We get several different effects related to agitation booboo’s. You posted a positive image (print) that reveals negative density streaks that correspond to the location of the sprocket holes on the film. Such negative density on a print (positive) relates to plus density streaks on the film.

 

 

Film develops in stages: First the developer solution must infuse into the gelatin emulsion. Once inside, it goes to work and quickly expires. This exhausted developer contains bromides from the emulsion. Bromides are a restrainer that retards developer. The presence of exhausted dev eloper thwarts replacement with fresh, active developer. The remedy is agitation.

 

 

Best – continuous agitation for 30 seconds followed by 5 seconds of agitation every 30 seconds. Best if the agitation is a random action, as patterned agitation sets up ebb currents that do exactly what you are seeing.

 

 

Ebb currents from the sprocket holes flush away the exhausted bromides. This contaminated developer is replaced with fresh robust stuff. The result is plus density streaks adjacent to the sprocket holes.

 

 

Conversely, if agitation is sparse, we get “bromide drag”. Areas of the film that have re received high levels of exposure are developed up to a high density. This high activity area contains abundant exhausted bromide- laden developer. If agitation is sparse, this spent developer eventually exits and under conditions of slight agitation, this fluid, being heavier than the fresh stuff, slowly drifts down under the influence of gravity. As this spent developer is slow to move, it shields the film against receiving fresh stuff. As this exhausted developer drifts down, it sets up ebb currents that bring in fresh fluid below the high density area. The result is plus density below the high density area.

 

 

Film makers place dots of high density on the edges of the film to help you identity bromide drag. Look at the edge printing. Do the black dots have a comma- like tail below them? If true, you have bromide drag, and this is due to insufficient agitation.

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That's all very well Alan, but I'm left wondering exactly how bad one's agitation has to be in order to provoke developer streamers?

 

I started developing film at the age of 11, long before the internet and its (sometimes dubious) free advice. I had no mentor, and only dated library books to guide me. After I'd experimented with sloshing the film through developer in a breakfast bowl, I saved up and bought a used developing tank. It was an old Johnson's 'twiddle stick' bakelite thing,

 

I continued to develop many rolls of film over the next 45 years or more, both professionally and on an amateur basis for my own pleasure.

 

I've used dip'n'dunk reels in cages in 3 gallon tanks, Colenta semi-automated rotary processors, Jobo rotary processors, plastic tanks and reels, stainless tanks and reels, small tanks, multi-reel tanks, large diameter tanks, and even open dishes.

 

Anyhow, the point is that absolutely none of those films, at any stage of my developing (sorry!) experience, has shown sprocket-hole streamers. Not one.

 

So exactly how does one go about ruining a film in such a way?

 

I'll freely admit to a whole range of other errors and mishaps - accidental fogging, under and over-developing, kinks, scratches, air-bells, drying marks. Yep, pretty much seen the lot...... but not sprocket streamers. Not a single one.

 

I can't believe I've been just lucky for all that time. What's the secret to producing them?

 

Having said that: What I definitely have seen are streaks from under-fixing or blixing with colour film. And this was fairly easily fixed (sorry again!) by putting the film back through a fresh fix/blix bath.

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I have seen lots of streaks that emanate from sprocket holes. I don't have all the answers but I know about ebb currents. It was researched at Kodak Park using IR photography and transparent developing tanks. These streaks are more prevenient if the developing time is short and the developer is energetic. The research was to improve uniformity in dip-and-dunk and roller transport machines. However, film on reels and sheet film in hard rubber tanks. This was in the 50's but I remember reviewing the IR movies revealing the bromine coming out of the film in solution and using nitrogen agitation to break up the ebb currents. As to the number of films I have developed, 55 + years in the photofinishing business and developing and printing machine manufacturing. Maybe a googolplex, maybe more. For 15 years, managed 7 labs, each doing 20,000 rolls a day. But -- I have been wrong a 1000 times or more!
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Soooo. How come stand development doesn't provoke sprocket streamers? It certainly reveals spent developer as a halo or adjacency effect, but it doesn't appear to dribble down the film from the sprocket holes.

 

At the other extreme we have rotary processing that never stands still. No sign of streamers there either.

 

Moderate inversion agitation? - No streamers. Twiddle-stick agitation? - Nope, not there either.

 

So forgive me for being a complete sceptic about the ability of 'incorrect' agitation to produce lines falling down from the sprocket holes, because; what exactly is that exact incorrect amount of under, or is it over, agitation?

 

The bromide drag or eddy-current theory sounds entirely plausible, but then so does the theory of a flat earth or a geo-centric universe if you ignore any evidence to the contrary.

 

If bromide dribbles down from the sprocket holes under gravity, then why does it affect both top and bottom of the film equally?

 

Likewise with eddy currents passing through the sprocket holes. Why don't they show as spiral turbulence tracks? And where does the sideways motion of the film come from to create a surge through the sprocket holes in the first place?

 

There are just too many holes (no, not again!) in the simplistic 'bromide drag' explanation I'm afraid.

Edited by rodeo_joe|1
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I don't know what the technical explanation is but I have certainly seen film that my students have developed with the venetian blind pattern corresponding to the sprocket holes, and in discussions with them discovered that they had indeed agitated continuously or close to it despite being instructed not to. I have seen this with both stainless steel tanks and plastic tanks that are agitated by inversion.

When I first bought my Jobo 4x5 tank and reels (using a Unicolor roller) and tried using the same HC 110 dilution and time that I used for roll film in stainless steel tanks and reels I got streaks in the direction of the rolling motion. A phone call to the Jobo rep got me to a more dilute HC 110 solution and taking the tank off the Unicolor roller once every minute and inverting the tank 3 times in 5 seconds. That solved the problem--no more streaks on 4000+ sheets through the tank.

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When I first bought my Jobo 4x5 tank and reels (using a Unicolor roller) and tried using the same HC 110 dilution and time that I used for roll film in stainless steel tanks and reels I got streaks in the direction of the rolling motion.

I got filling and foaming marks the first couple of times I used the 5x4 insert in my Jobo tank + CPE-2 processor. Following advice on this forum I started using a water pre-bath and the problem went away.

 

I've never had streaks though. The CPE-2 automatically reverses the direction of rotation every so often.

 

WRT sprocket-hole streamers. From your constant agitation anecdote, it appears that maybe standing waves in the developer are responsible? Still difficult to envision the exact mechanism though.

Edited by rodeo_joe|1
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Soooo. How come stand development doesn't provoke sprocket streamers? It certainly reveals spent developer as a halo or adjacency effect, but it doesn't appear to dribble down the film from the sprocket holes.

 

At the other extreme we have rotary processing that never stands still. No sign of streamers there either.

 

Moderate inversion agitation? - No streamers. Twiddle-stick agitation? - Nope, not there either.

 

So forgive me for being a complete sceptic about the ability of 'incorrect' agitation to produce lines falling down from the sprocket holes, because; what exactly is that exact incorrect amount of under, or is it over, agitation?

 

(snip)

 

Having not actually done stand development, as I understand it you agitate normally at the beginning,

and then leave it for a long time without agitation.

 

Most of the development will be done during the first minutes, maybe the first minute.

After that, development is slow enough not to streak.

 

I suspect that to get the indicated streaks, it is no agitation at all.

 

I often use Diafine, which has specific agitation instructions, too much or too little is bad.

Specifically, some in the first seconds, and then every minute after that. Similar to stand, it

relies on continued development of shadows, but does it in three minutes!

 

Note that the OP did not indicate agitation during fixing, when I suspect the problem occurred.

-- glen

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