Q-dog
Established
Hi,
What happened here? I shot a roll of Neopan 400 in my Rolleiflex. Developed it in Rodinal. Stand development 1:100 (5ml Rodinal) for 60min. Some of the negatives have pretty large (a few mm in diameter) roundish dark spots on them. What could be the cause? Attached is a part of the negative with the most prominent spots. Sorry, no attached since even a file of a few kB exceeds my quota, even though I have deleted all earlier attachements. But maybe you get the idea, large spots, no dust, scratches or anything like that. And taken on a cloudy day outdoor, so no flare or strong lights involved.
/Ola
What happened here? I shot a roll of Neopan 400 in my Rolleiflex. Developed it in Rodinal. Stand development 1:100 (5ml Rodinal) for 60min. Some of the negatives have pretty large (a few mm in diameter) roundish dark spots on them. What could be the cause? Attached is a part of the negative with the most prominent spots. Sorry, no attached since even a file of a few kB exceeds my quota, even though I have deleted all earlier attachements. But maybe you get the idea, large spots, no dust, scratches or anything like that. And taken on a cloudy day outdoor, so no flare or strong lights involved.
/Ola
Bob Michaels
nobody special
I have developed a lot of Neopan in Rodinal and never had any spots. But I agitate once per minute.
Do you have this spot problem if you develop them normally?
Do you have this spot problem if you develop them normally?
Freakscene
Obscure member
Maybe you could show us what they look like.
Did you use acid stop bath? Neopan is more sensitive than most modern films to sudden pH changes. This can be accentuated in some kinds of water. This usually causes reticulation but can also manifest as dark spots when the emulsion has tiny holes in it, leaving only the film base.
This is an occasional phenomenon, but I have seen it enough times in other people's negs to know it is real, but it's never happened to me although I use a citric acid stop bath. Why? I don't know, maybe it's because the citric acid is less acidic than acetic acid, maybe it's because I use distilled water for all my processing, maybe it's because I tightly control my development temperature, it could be how far south I live [joke] really, I just don't know.
Marty
Did you use acid stop bath? Neopan is more sensitive than most modern films to sudden pH changes. This can be accentuated in some kinds of water. This usually causes reticulation but can also manifest as dark spots when the emulsion has tiny holes in it, leaving only the film base.
This is an occasional phenomenon, but I have seen it enough times in other people's negs to know it is real, but it's never happened to me although I use a citric acid stop bath. Why? I don't know, maybe it's because the citric acid is less acidic than acetic acid, maybe it's because I use distilled water for all my processing, maybe it's because I tightly control my development temperature, it could be how far south I live [joke] really, I just don't know.
Marty
Q-dog
Established
Thanks for your replies. Since I could not make any attachement yesterday I tried to put the picture in the gallery instead. And it worked. Appart from showing that a TLR in my hands is not a good tool to capture a child prone to sudden movement you can also see three white spots. I think the shot is at 5.6/30 or so rating the film at 320. I use just tap water (pretty soft here) as stop bath.
Now, lets see if I can get the image to show:
Now, lets see if I can get the image to show:
HTML:
[IMG]http://http://www.rangefinderforum.com/photopost/data/500/Scan-120109-0007.jpg[/IMG]Bob Michaels
nobody special
Looking at the image in the gallery, it looks like air bells or air bubbles to me. Although they seem to be quite large on a 2 1/4 square negative.
I have never had this problem personally. But I develop 120 Neopan in Rodinal with agitation as is normal.
Do you have this problem with normal development? Is there some reason you are using a non-standard (ie. "stand") development?
Freakscene
Obscure member
Agree, but I've seen lots of bubbles this big on stand developed negs.
I'd ditch stand development as a process. I have never seen any evidence that stand development is better than very gentle, minimal agitation, and it is often considerably worse because it introduces a lot of problems, like this one. In very dilute solutions of Rodinal, the times people discuss are often much longer than the time after which no additional development will occur. It's easy to establish that time under your own conditions with a little experimentation and sensitometry (all you need to do this is a flatbed scanner).
Marty
Q-dog
Established
It could be airbubbles, but big ones for sure. The reason for stand development is that I tried it before with Rollei retro with good results. And I wanted to try how it worked with Neopan. I have another roll finished, rated a bit lower at 250, and I will use a more conventional method for that. Suggestions are welcome. But I will use Rodinal, that is what I have at home.
/Ola
/Ola
Freakscene
Obscure member
I have found that Rodinal 1+100, 20 min with very gentle agitation at no more than 20C works just fine.
Marty
Marty
Q-dog
Established
At what interval do you agitate, every 3 min or?
Freakscene
Obscure member
I use one gentle inversion every minute. Give it a tap to dislodge bubbles. If you want more compensation you can increase the inversion interval to 2 minutes. It's somewhere to start anyway; from there you can experiment and get it right for you.
Marty
Q-dog
Established
Thanks Marty,
I followed your suggestions and my second roll came out ok. It seems I should rate it even lower than 250 or maybe increase development a bit but it is a good start.
Ola
I followed your suggestions and my second roll came out ok. It seems I should rate it even lower than 250 or maybe increase development a bit but it is a good start.
Ola
sepiareverb
genius and moron
Um, Airbells cause thin spots in the negative, thus dark spots on the print.
Freakscene
Obscure member
Indeed. Sometimes I am so thick - it didn't even register if I was looking at a negative or a positive.
To the OP - was the film out of date or poorly stored, or stored for a long time after exposure? I have seen spots like this on old film where the incorporated development accelerants have been initiated by age, not development, and areas of the neg go black. It was quite common on expired Fomapan T800/Peterson Acupan 800.
Glad to hear it worked. I generally get about EI200 out of the 400 speed films with Rodinal.
Marty
Bob Michaels
nobody special
Damn Bob, Marty and I were feeling so smug about diagnosing the problem. Of course, you are right and our diagnoses make no sense.
I wish I could come up with some clever explanation for my error but will just have to blame it on a brain f*rt.
newsgrunt
Well-known
Funny but the spots look like they have similar shapes. Were there any bright lights poking through the fence you may not have noticed while taking the photo ? Otherwise, perhaps you inadvertently dropped a few drops of Rodinal on the film somehow ?
Freakscene
Obscure member
I wondered about this and it almost looks like the blobs are on top of poles, suggesting that they are lights. The OP said these appeared on several frames, so maybe it was just unfamiliarity with the rendering of OOF very bright highlights.
Marty
newsgrunt
Well-known
Hey Q Dog,
can you post the other frames with spots ?
can you post the other frames with spots ?
Q-dog
Established
Thanks all for your input.
I just came back from a late jogging round and passed the playing grounds where I took the shots. I realised that the new lamps they have put up are really strong. So that is a possible explanation even though It surprises me. I will have a look at the negatives again in the weekend. Need to take a shower and go to bed now.
And the film is also expired I am sure. So another possibility...
Ola
I just came back from a late jogging round and passed the playing grounds where I took the shots. I realised that the new lamps they have put up are really strong. So that is a possible explanation even though It surprises me. I will have a look at the negatives again in the weekend. Need to take a shower and go to bed now.
And the film is also expired I am sure. So another possibility...
Ola