Diagnosing black spots on scanned negatives, recently becoming a problem.

I've noticed on a recently developed roll of film that black spots were appearing all over each of the photos. I noticed it after developing and scanning a roll of TMAX 400 but, looking back at previously scanned rolls of film (mostly Delta 400) I might be seeing the same issue albeit much fainter and less apparent.

Photo 1 (TMAX 400 @ 400 iso) - The worst of the rolls, perhaps due to the fact this roll had more contrast. It's all over but the sky is the easiest area to spot (enlarge the image).


Photo 2 (Delta 400 @ 400 iso) - Not as bad... but it does look like something is there... Lower contrast negative. Most apparent in the upper left corner (enlarge the image).



Photo 3 (Delta 400 @ 400 iso) - Not too bad, maybe it's not even the same thing and its just normal grain/scan effects? Lower contrast negative... The darker parts of the sky might be the area affected (enlarge the image).


The 3 photos come from 3 different rolls of film developed the same way using the same fixer and developer concentrate from the same bottle. The fixer (TF-4) and developer (DD-X) are relatively fresh (within the past month or two). The LFN Wetting Agent I use in the final rinse is about 1 year old, is that problematic?

General development method:
1) 100ml DD-X + 400ml of distilled water at 20c poured into the tank. Developed for 8 mins with 4 rotations of the tank each minute, tapping the tank to remove air bubbles, then emptied.
2) 2 mins of running tap water at ~20c (not exact give or take a few degrees) as a stop. Then, filled the tank twice with tap water and agitated for 30 seconds, then emptied.
3) Poured in 500ml of the TF-4 fixer (mixed with liquid concentrate and distilled water, working solution previously used < 10 times). Rotated tank 2 times every 15 seconds for 6 mins, tapping the tank each time to remove air bubbles, then emptied.
4) Ran tap water at ~20c for 5 minutes as a rinse, then emptied.
5) Poured in 500ml of distilled water + 2-3 drops of LFN wetting agent, agitated for 30 seconds as a final rinse.
6) Removed film from tank, shook off excess water, and hung to dry. I did not squeegee or touch the film, only air dried. They were hung in a bathroom where I recently ran hot water to steam the air and remove dust.
7) Rinse out the tank and dry everything before moving onto a new roll.

I've developed over 50 rolls of film using this same method and same types of chemicals and it appears to only be a recent problem...

The chemicals are stored in my apartment that can reach 80f+ in the day time (I doubt this was a problem since I don't see it in rolls I developed last summer when it was hot). When I'm preparing the chemicals to use I will cool them down in a measured/mixed amount in the refrigerator to bring them to 20c (otherwise they're several degrees too warm).

I assume it has to be the chemicals... my tap water hasn't changed and I use distilled water for dev, fix, and final rinse. This is most apparent with the roll of TMAX but it appears somewhat in the Delta 400 (maybe ?).

Should I dump my fixer?
Was it my developer? (the bottle of concentrate is nearly empty, so I can dump the rest without much waste)
Is the 1 year old LFN wetting agent to blame?
Bad distilled water, if even possible?

I'm not opposed to just dumping all my chemicals and starting fresh, I just would want to know if it's something I'm doing that could cause this to happen again in the future...

dump your fix. I've had the same problem. the black spots are tiny holes in the emulsion. If they were particulate from dirty fix, then they would be white spots. I'm not sure why the fix was the problem for me, but it was. Others have suggested highly acidic stop but that's not your problem, given your water stop.

John M Austin said:

dump your fix. I've had the same problem. the black spots are tiny holes in the emulsion. If they were particulate from dirty fix, then they would be white spots. I'm not sure why the fix was the problem for me, but it was. Others have suggested highly acidic stop but that's not your problem, given your water stop.

Click to expand...

That can be my next adjustment. The developer for next time will be from a new bottle by virtue of the current bottle being nearly empty so, that's another variable I can account for. Did you only ever see this with one batch of fixer? I'm curious if it's just bad luck or something I did when storing, using, and or mixing the fixer?

I can see the problem in photo #1, but #2 and #3 look quite healthy to me.
Particulate matter in the developer may be the issue, although it could also be associated with backing paper or dust on the film during exposure. If processing is suspect, the development step would be the first I would scrutinize.

Many others, including myself, have had this problem on and off over the years, and it's quite a common question of photo forums.

But think how small these dots must be on the negative, that they are only just visible when the negative is enlarged quite a lot. I doubt you'll even be able to see anything with the naked eye on the negs.

In the past when I had the problem, I ended up buying a decent water filter that attaches to the tap. Along with this, I also filter all water and solutions used in the processes, just before use (even distilled water = why not be over cautious?) For this I bought a Paterson filter funnel, which has a fine metal mesh, which along with the tap filter, takes out anything in the water and processing chemicals that might cause any problem on the negs. Just remember that one cannot be over clean and cautious when developing films.

I hope these comments may be of some help to you.

Terry S

tezzasmall said:

But think how small these dots must be on the negative, that they are only just visible when the negative is enlarged quite a lot. I doubt you'll even be able to see anything with the naked eye on the negs.

Click to expand...

Troubleshooting a somewhat similar problem sometime ago (which ended up film manufacturing defects, but this aside) tells me that the marks we see here must be in the order of magnitude of 5um. I'm not sure what kind of tap filter you're using, but a metal mesh filter is apparently 20um, which will therefore allow the kind of particles that would cause this problem here to pass through freely.

koraks said:

I can see the problem in photo #1, but #2 and #3 look quite healthy to me.
Particulate matter in the developer may be the issue, although it could also be associated with backing paper or dust on the film during exposure. If processing is suspect, the development step would be the first I would scrutinize.

Click to expand...

Perhaps I'm being overly critical of #2 and #3, to be fair I didn't notice any issues with those other rolls until I developed the roll #1 came from. I make a point blow air with a duster routinely to clear out any dust from the film holder & body. I feel like I wouldn't be getting this much dust if at all from the standpoint of the camera.

tezzasmall said:

Many others, including myself, have had this problem on and off over the years, and it's quite a common question of photo forums.

But think how small these dots must be on the negative, that they are only just visible when the negative is enlarged quite a lot. I doubt you'll even be able to see anything with the naked eye on the negs.

In the past when I had the problem, I ended up buying a decent water filter that attaches to the tap. Along with this, I also filter all water and solutions used in the processes, just before use (even distilled water = why not be over cautious?) For this I bought a Paterson filter funnel, which has a fine metal mesh, which along with the tap filter, takes out anything in the water and processing chemicals that might cause any problem on the negs. Just remember that one cannot be over clean and cautious when developing films.

I hope these comments may be of some help to you.

Terry S

Click to expand...

You can't see them on the negative by eye. You're right that it's fairly undetectable unless you zoom in or are looking for it and only the TMAX roll is truly an issue. I'll have to see what it looks like on a darkroom print if I should ever be inspired to make any prints from that roll.

I suppose I can pick up the Paterson filter to start using, it's cheap and might save me issues down the road. How long do those filters last assuming they're cleaned? Can I safely run the mixed solution of the fixer/developer through the filter?

koraks said:

Troubleshooting a somewhat similar problem sometime ago (which ended up film manufacturing defects, but this aside) tells me that the marks we see here must be in the order of magnitude of 5um. I'm not sure what kind of tap filter you're using, but a metal mesh filter is apparently 20um, which will therefore allow the kind of particles that would cause this problem here to pass through freely.

Click to expand...

Yeah, a lot of the spots aren't exactly big. The film I was using was not expired and was stored in a fridge. I will note the the TMAX roll sat in the camera for ~2 weeks before I finished it. Though, the camera wasn't exposed to any harsh environments and it's not like it was only a part of the roll...

avizzini said:

I suppose I can pick up the Paterson filter to start using, it's cheap and might save me issues down the road. How long do those filters last assuming they're cleaned? Can I safely run the mixed solution of the fixer/developer through the filter?

Click to expand...

I've had one for 30 years plus and it's till going strong. The metal mesh filter can be taken out after each use, just be simply unscrewing it. One then puts it back in the other way up and flushes water through to clean it. Simple eh?!

And yes, you can run your chemical solutions through it, as it's something I have always done.

koraks said:

Troubleshooting a somewhat similar problem sometime ago (which ended up film manufacturing defects, but this aside) tells me that the marks we see here must be in the order of magnitude of 5um. I'm not sure what kind of tap filter you're using, but a metal mesh filter is apparently 20um, which will therefore allow the kind of particles that would cause this problem here to pass through freely.

Click to expand...

But as Koraks does say, some particles are smaller than the mesh filter size, so obviously some may still get through, but it's a good start. In time you may want to, as I did, purchase a more advanced and i.e. more expensive, water filter if the problem continues, but you'll never know unless you try.

Terry S

tezzasmall said:

I've had one for 30 years plus and it's till going strong. The metal mesh filter can be taken out after each use, just be simply unscrewing it. One then puts it back in the other way up and flushes water through to clean it. Simple eh?!

And yes, you can run your chemical solutions through it, as it's something I have always done.


But as Koraks does say, some particles are smaller than the mesh filter size, so obviously some may still get through, but it's a good start. In time you may want to, as I did, purchase a more advanced and i.e. more expensive, water filter if the problem continues, but you'll never know unless you try.

Terry S

Click to expand...

None the less the filter may cut back on the occasional negative artificat I find at times, unrelated to this issue. I imagine it'll also be an improvement for my darkroom printing chemicals since I use tap water for mixing those chemicals.

Another thing I'm considering as a potential problem spot was that I don't remember if I properly cleaned the chemical jugs of fixer after emptying the old fixer and putting in the new fixer...

The bad news is that the quality of the water in the U.S. seems to vary a lot - not surprising in such a large country but the good news is that distilled water seems to be cheap. It may make sense to develop film in distilled water at least and maybe stop and fix with distilled water as well. Once the negatives are in pristine condition then I'd have thought that filtered "tap" water for print processing was OK

pentaxuser

pentaxuser said:

The bad news is that the quality of the water in the U.S. seems to vary a lot - not surprising in such a large country but the good news is that distilled water seems to be cheap. It may make sense to develop film in distilled water at least and maybe stop and fix with distilled water as well. Once the negatives are in pristine condition then I'd have thought that filtered "tap" water for print processing was OK

pentaxuser

Click to expand...

The developer & fixer were/are mixed with distilled. As well as the final rinse with a couple drops of a wetting agent. It's just the stop that's tap water. I've not had an issue like this with the previous 40 some rolls... Only the last few.

avizzini said:

The developer & fixer were/are mixed with distilled. As well as the final rinse with a couple drops of a wetting agent. It's just the stop that's tap water. I've not had an issue like this with the previous 40 some rolls... Only the last few.

Click to expand...

If you have only been having problems recently, it could be a build up of something in your stop, so putting it through the Paterson funnel filter would do no harm and may even sort out your problem. If any other of your liquids are reused, like the fixer for example, this could easily be put through it as well before use.

Terry S