Emulsion problems in MF Delta films?

[psvensson]

I keep getting pinholes, i.e. small spots where the emulsion seems to be missing, on 120 rolls of Delta 400 and 3200, and I'm starting to think it's a manufacturing problem. It's been particularly severe on 3200, but practically every one of perhaps 25 rolls of Delta 400 120 has at least one pinhole. Anyone else have similar experiences?

I don't think the problem is with my processing, because I develop other films, including 35mm Delta 400, and have had no problem with those. I don't use developers with carbonate, and I use water instead of an acid stop bath (not that I think either one presents a major risk for pinholing).

I recently switched to 120 Tmax 400, and had no pinholes, but I miss the finer grain I get from Delta 400. And there's no high-speed film to replace Delta 3200 in 120, AFAIK.

Sorry, I don't have any emulsion numbers. This has all been fresh film bought at B&H throughout the year.

 

[pentaxuser]

I keep getting pinholes, i.e. small spots where the emulsion seems to be missing, on 120 rolls of Delta 400 and 3200, and I'm starting to think it's a manufacturing problem. It's been particularly severe on 3200, but practically every one of perhaps 25 rolls of Delta 400 120 has at least one pinhole. Anyone else have similar experiences?

I don't think the problem is with my processing, because I develop other films, including 35mm Delta 400, and have had no problem with those. I don't use developers with carbonate, and I use water instead of an acid stop bath (not that I think either one presents a major risk for pinholing).

I recently switched to 120 Tmax 400, and had no pinholes, but I miss the finer grain I get from Delta 400. And there's no high-speed film to replace Delta 3200 in 120, AFAIK.

Sorry, I don't have any emulsion numbers. This has all been fresh film bought at B&H throughout the year.

I know we shouldn't use him as a customer relations call centre but maybe if others echo these problems then Simon from Ilford might appreciate knowing about it.

He might have read this thread anyway so you may hear something. If a rogue batch has got out and Ilford are unaware of it then I am sure they'd want to know.

Pentaxuser

 

[fschifano]

Haven't heard of, nor do I use Ilford's Delta films so take this for what it's worth. Every time I've had a similar problem with LF films the problem traced back to dust on the emulsion blocking light from reaching that portion of the film. I realize that scenario is unlikely with medium format films and even less so with 35mm. Still, it's worth checking into. It's not impossible that some dust is floating around inside your camera and some of it stuck to the film. Static electricity is a real problem in the norther hemisphere this time of year what with relative humidity levels being very low in heated buildings. If there is emulsion damage, you should be able to feel it. A real pinhole is a separation of the emulsion from the film support.

 

[john_s]

......... A real pinhole is a separation of the emulsion from the film support.

Can you get access to a binocular dissecting microscope? A cheap students' model would be quite adequate. I think you would be able to see the actual surface, to see if there is a discontinuity in the emulsion.

 

[psvensson]

Every time I've had a similar problem with LF films the problem traced back to dust on the emulsion blocking light from reaching that portion of the film. I realize that scenario is unlikely with medium format films and even less so with 35mm. Still, it's worth checking into. It's not impossible that some dust is floating around inside your camera and some of it stuck to the film.

I initially thought it was dust and crumbling foam in my film backs. But I've cleaned them thoroughly and replaced the foam, and I don't get any pinholes with Tmax or color film in the same backs.

You're right, I should try to feel for the spots.

 

[George Collier]

Shouldn't be a problem today, but what you describe sounds like a something people used to experience many years ago from too strong a stop bath, reacting to the alkaline developer and resulting in small "eruptions" (for lack of a better term) in the emulsion, looking like pinholes. I never had the problem, I always used an acid stop that had almost no acetic in it, just enough to stop the action. Don't know if this is the problem (not likely with today's emulsions), but maybe a clue.

 

[psvensson]

I felt for the holes this evening, and there's nothing. Neither is any damage to the emulsion visible, so these are probably not real pinholes. This makes me wonder again if dirt might be responsible, but that's hard to believe.

Here's a crop of a Delta 3200 120 neg showing a black speck, clear on the negative.

 

[digiconvert]

I trained as an industrial chemist (including some time dealing with surface coatings) and the black areas on your neg seem to be far too large and irregular in shape and distribution to be caused by pinholing due to any kind of chemical cause. They do look as I would expect from a physical cause such as dust on the unexposed film or physical damage to the emulsion (either through a scratch or poor adhesion of the emulsion to the substrate) .
If there were poor adhesion to the substrate it may be caused by contamination, again I would have expected far more widespread loss of adhesion.
None of this completely discounts the possibility of a rogue batch of substrate or emulsion, I would suggest you contact Ilford through this link http://www.ilford.com/html/us_english/directory/directory.asp
and ask them for a comment, obviously batch numbers etc. would be useful but I know how much notice I take of these !
Hope this is helpful
CJB

 

[psvensson]

Ahem, I just got similar spots on two rolls of Tmax 400. So I think I can rule out emulsion problems (I'd change the title of the thread if I could!)

It has to be dirt. The odd thing is that it's in chunks or flecks. If it was just general household dirt I'd expect most of it to be fibers, like the dust that gets on negatives in the darkroom. I wonder if maybe I have crumbling foam somewhere inside the body (a Bronica SQ-A) or if static electricity contributes to the problem.

 

[Photo Engineer]

Pinholes caused by acidic stops or fix baths is pretty much a myth, especially with modern films.

I coat my own film and paper and use an acid stop and fix. I use glyoxal or chrome alum as hardener, and at 68 degrees I see no problem unless I make an error in the amount I add or the time I let the coating harden.

Peter, the spots are not indicative of any coating defect that I know of but there is one called 'pick off' that slightly resembles what I see. It takes place when one layer of film sticks to another when moist or damp and then is pulled apart. The emulsion layer sticks to the base and is then 'picked off' when pulled apart. This can also happen when film sticks to paper base.

Could your film have been refrigerated and opened too soon so that moisture condensed on it? Could it have been re-frozen? Is it humid when you open a pack? These are questions I would answer if I saw what you are seeing.

Another is this. Do you have a home humidifier? Some of these accumulate salts on the element that vibrate off into the air and form large 'dirt' particles that float like fine ash in the air and then drift onto things. Ours did that and I had to turn it off finally. That is another source of this type of problem.

PE

 

[psvensson]

Peter, the spots are not indicative of any coating defect that I know of but there is one called 'pick off' that slightly resembles what I see. It takes place when one layer of film sticks to another when moist or damp and then is pulled apart. The emulsion layer sticks to the base and is then 'picked off' when pulled apart. This can also happen when film sticks to paper base.

Could your film have been refrigerated and opened too soon so that moisture condensed on it? Could it have been re-frozen? Is it humid when you open a pack? These are questions I would answer if I saw what you are seeing.

Thanks, PE. If this was the case, I should be able to see or feel physical damage to the emulsion, right? There would be a little pit or discontinuity?

Another is this. Do you have a home humidifier? Some of these accumulate salts on the element that vibrate off into the air and form large 'dirt' particles that float like fine ash in the air and then drift onto things. Ours did that and I had to turn it off finally. That is another source of this type of problem.

PE

Interesting, but no, no humidifier. Now that you point it out, some of these specks seem to large to float in the air very long. I guess that points to some source in the camera, back, or film.

 

[Photo Engineer]

Pick off creates small 'craters' in the film that are irregular in shape and may go to any depth right to the support. The humidifier problem creates raised spots.

The first causes dark spots on prints and the second causes light spots on prints. I should have considered the latter more carefully when I posted it, as yours appear to be all irregular dark spots.

Just remember that most all coating defects are rather regular or smooth in shape like dots, comets, circles, or streaks, and cause depressions that resemble craters with sometimes raised lips just like craters. They most often are oriented in the direction of coating, which in normal film is lengthwise.

PE

 

[psvensson]

Just remember that most all coating defects are rather regular or smooth in shape like dots, comets, circles, or streaks, and cause depressions that resemble craters with sometimes raised lips just like craters. They most often are oriented in the direction of coating, which in normal film is lengthwise.

PE

Interesting. These don't look anything like that.

 

[Simon R Galley]

Reply From Simon @ILFORD Photo / HARMAN technology Limited

Dear Pinhole Sufferer,

I do not think its the film .....firstly, yes we do have QC's ( quality complaints ) and sometimes it is a problem with manufacturing but
I have to say compared with the millions of square metres of photo products we manufacture it is very, very rare, our own QC procedures and testing at every stage of manufacturing and finishing normally eliminate 99.99% of any
product at risk of being sub standard. But as you will see and read from people like Photo Engineer and other very knowledgeable APUG readers
the manufacturing process for film and paper is quite a science and in all
science and manufacturing things can occasionally go wrong.

So if you have a problem, wherever you are in the World contact your local distributor, they have to deal with your QC in the first instance, we have some very skilled people who can examine the problem, that is a filter as we have three levels of reply to any QC 1) Cause justified - A product problem, 2) Cause not certain - just that, we just do not know how the problem occured and we cannot tell if it was pre or post processing 3) Cause not justified - A problem that is not in manufacturing or our storage : As I am sure you will realise the vast majority are CNJ (3)

If the distributor cannot identify the problem, having normally discussed with our complaints people here in the UK it will be sent to the factory for further examination, especially emulsion issues as we have an electron microscope and other sophisticated test equipment not available to distributors.

Whatever, the customer should get a reply as 1) 2) or 3) : If it is 1) we obviously replace the goods and the postage etc.

So if you have a problem with one of our products and you do not know what it is speak to your distributor :

As someone correctly said, the first thing we need is the batch number, without that we can do little, so make sure you always make a note, especially film batches, paper is easier as most people do not throw away our envelopes or boxes.

As to this problem, please do as I suggest contact the US distributor, I would not pre-judge this issue, but I can tell you we have no current QC issue with DELTA films of any type, and as you have this on 400 and 3200 these are different emulsions ( and bases ) it sounds like it could be dust, but send it to us, we will check it out and let you know ...its as easy as 1) 2) 3)

Sorry you have had this problem, thanks for using our products:

Simon @ ILFORD Photo / HARMAN technology Limited

 

[psvensson]

As to this problem, please do as I suggest contact the US distributor, I would not pre-judge this issue, but I can tell you we have no current QC issue with DELTA films of any type, and as you have this on 400 and 3200 these are different emulsions ( and bases ) it sounds like it could be dust,

Thanks for the answer! That's good service. I think I have concluded that dust is to blame.