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barnacle
14-Feb-2016, 15:26
Just puzzled as to what the following marks might be - here's the whole image (scaled to a sane size):

http://www.dnbprojects.co.uk/Ely/0423.jpg

The most obvious faults are the two white stripes - just above the window, and on the head on the left lintel.

146587

There are some solid black areas on the tiles:

146588

And one area that's neither one nor the other:

146589

These are not scanning errors (though there is dust on the scan - a very rough and ready scan) - they're in the negative. The white stripes are there in the silver; the black bits don't look like missing emulsion, and I have no idea what's going on in the last one - it's there on the neg.

Any thoughts?

Neil

vinny
14-Feb-2016, 15:40
What film?

barnacle
14-Feb-2016, 16:23
Adox CHS 50 - a couple of years out of date. But check the 'show your churches' thread in the pictures section for three more from the same batch, same place, same day, same developing tank.

Neil

vinny
14-Feb-2016, 17:09
Adox, There's your sign.

Paul Metcalf
14-Feb-2016, 17:25
White marks sure look like hair/fuzz to me at time of negative exposure. Not sure about the others if they're also on the negative.

barnacle
15-Feb-2016, 00:08
Hair on the negatives would show black on the final image, no?

Neil

Thalmees
16-Feb-2016, 06:56
It could be static electricity !
The black areas might be a precipitate during the development.
The grey area, could it be in the subject ?

Paul Metcalf
16-Feb-2016, 07:23
yeah, sorry brain fart on my part. Was thinking negative when looking at images.

barnacle
16-Feb-2016, 09:18
No worries, Paul! We've all done it...

Thalmees, I don't *think* the grey area was there in the subject, but it's possible. Static... well, I did wonder about that but I would have expected a more 'feathery' line - though I admit I have never seen static on a film before, and it *was* a new box of film, wrapped in plastic, in a nylon changing bag, on a dry winter day - classic opportunities for static to be generated. I can't see a precipitate from the development given (a) that it was continuous development, and (b) three others in the same batch show no sign of it.

I'm leaning to a film fault of some type.

Neil

Thalmees
18-Feb-2016, 07:42
Hello Neil,
Static usually choose the best negative, but fortunately it does not know yet the best place on the negative. I'm talking about my static. Yours, looks it does know where to hit !!!
Why you do not elaborate on film(type/size) and processing ?
Lots of photographers around(LFPF) are so kind to share their experiences on this topic.

barnacle
18-Feb-2016, 08:59
Sorry - forgot the status! It's my current brew: 4x5 Adox CHS 50 (the last box - couple of years out of date) developed in R09 at 50:1, 8 minutes, orbital developer, 4 sheets at a time.

Neil

Thalmees
20-Feb-2016, 07:27
Neil, thanks for the information.
Another reason to think of precipitate during development, is the Paterson Orbital Processor.
Beautiful daylight processor, use it from time to time for semi stand development.
I do not know R09, but I think it's a thick syrup like Kodak HC110.
From my reading and following in photographic communities, R09 is no1 adopted film developer ever among photographers. I think will settle on R09 someday after I finish trying all developers I have now.
The old partially filled bottle of HC110 had a precipitate at the bottom.
I think if used without paying attention to re-dissolve the precipitate before mixing(or at least leaving it at the bottom), it could cause black marks like that on your film.
The black areas in your film, does not necessarily being really black in its self. It's only a non-transparent precipitate that has illuminated(by the scanner lamp) from behind.
Fixer by the way, will develop a precipitate if left enough in a tray.
If my suspicions turned to be true, do not try to peel the precipitate at all.
Try first to know on which side is the black marks. If it's not on the emulsion side, you are lucky, or did not put the film in the processor as advised(emulsion face up), or both.
Confirm by vision, that it's something laid on film not a manufacturing film defect. Examine both surfaces of film under strong spot light.
If I'm using undo-redo technology, will not bother correcting the negative. Will leave the negative alone, will correct on Photoshop.
Or, try to gently clean the negative by any film cleaner like PEC-12/PEC-PAD.
But, if the negative is to be used for optical photographic printing, and the film cleaner has failed to remove the black areas, you may do the following:
This is not a formal or a verified advice. It could damage your film.
Re-soak the film in distilled water, 10min or more. If the precipitate did not go by its self, use a wet clean hand(or soft tissue like pic-pad), try to smear the film very very gently with your finger.
Again, this is not a formal or a verified advice, and could damage your film.
Please let us know what marks are that on your film, and how did you manage to resolve like this type of problem.
Thanks.

barnacle
20-Feb-2016, 09:45
Thanks, Thalmees.

I'm currently in Berlin, rather than at home in the UK, until March, so it will have to wait.

However, I *can* confirm that the black mark on the negative that caused the white flash under the window is visible on the negative, and was so immediately I looked at the film after washing and before drying; it had the same density and colour as the other fully exposed parts of the negative - i.e. it looked like silver in the emulsion had been exposed to something.

I can't comment on the black areas (which must have been clear on the negative) from memory, but I'll investigate further when I return home.

The developer itself isn't particularly syrupy - it feels little different in viscosity from plain water. I use minuscule amounts - 3g weighed and made up to 150ml with water (49:1) - for the orbital processor. The film is always placed emulsion side up. One issue with the orbital processor is that initially I was having problems with the back of the film sticking to the bottom of the tank and the anti-halation layer not fully clearing, but this didn't occur on this batch. (I think I've solved that by graving grooves and ripples in the bottom of the tank and carefully removing any sharp edges).

Neil

Sirius Glass
20-Feb-2016, 13:53
Static discharge from very dry air and advancing the film too quickly or removing the dark slide too quickly.

Mfagan
20-Feb-2016, 18:41
I spent about 20 years in the aerial imagery field (a long time ago), saw the effects of static on aerial film sveral times, and believe that it's a reasonable suspicion for the dense streaks in the negative in this case.

Sirius Glass
20-Feb-2016, 19:11
Welcome to Large Format Photography Forum

Jim Jones
20-Feb-2016, 19:13
The static I've encountered on 35mm film in extreme cold looked nothing like these flaws.

Michael Clark
22-Feb-2016, 20:30
The top wormy one looks like a reflection off the edge of an archway inside the dark inside's of the church.

barnacle
23-Feb-2016, 02:24
Aye, but there's nothing there for it to reflect!

I wondered about a particularly shiny insect flying through the shot (exposure was a second or two).

Neil