StevenJ
newbie
Reged: 25/10/2005
Posts: 19
Loc: Glasgow
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I have had a break from the darkroom for considerable time (3 years) and I'm loving it again. Tonight I have just developed 3 films at my local camera club, two ilford, and one Fuji.
The last one I developed was a fuji across 400. After developing & fixing - I was rinsing the chemicals off afterwards, and the water in the dev tray kept getting clouds of pink in it. When I took the film off the spool, even more water turned pink.
Does anyone have any idea what this is? I have never seen this before.........
Kind regards
Steven
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zx9
old hand
Reged: 22/06/2007
Posts: 907
Loc: London
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I have noticed that too, most obviously with APX in Rodinal but to an extent with other dev. film combinations.
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ZX9 (Keith)  
My Flickr Pictures
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StevenJ
newbie
Reged: 25/10/2005
Posts: 19
Loc: Glasgow
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when you say that you have noticed that, is that with the Fuji Acros film? I was using Ilford developer. I forget exactly which one (my photography isn't good enoght to experiment with all different developers!)
thanks, Steven
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zx9
old hand
Reged: 22/06/2007
Posts: 907
Loc: London
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No it was Agfa APX 400 and TMAX, it's the anti-halation dye added to the back of the film intended to increase contrast by stopping light been reflected back from / by the substrate. In some films it forms a dark red cloud when combined with the thiosulphate in the fixer. ( IIRC it's a long time since I did photoscience ) Sorry my first reply was not so informative but I have been pondering it all morning.
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ZX9 (Keith)
My Flickr Pictures
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beejaybee
Marvin
Reged: 18/07/2007
Posts: 4463
Loc: Really Here In Name Only
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Quote:
it's the anti-halation dye added to the back of the film intended to increase contrast by stopping light been reflected back from / by the substrate. In some films it forms a dark red cloud when combined with the thiosulphate in the fixer.
Hmm - why does it not come off in the pre-soak (if you use one) or in the developer? I use a pre-soak (water with a couple of drops of wetting agent) and am quite used to seeing that being dirty grey when poured out. But the reason for the pre-soak is to ensure that the developer acts evenly without having to agitate too much, which can spoil the acutance properties of the soup.
Is there a bit of emulsion under a sticky label (used to attach the spool perhaps) which is only getting wet at the end of the process?
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PeteE
enthusiast
Reged: 23/08/2005
Posts: 396
Loc: BRENTWOOD,Essex
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I just developed a short length of 35mm Fuji Acros 100 as a test in Rodinal 1+50 @ 18oC for 11.5 minutes and there was NO pink effect- maybe it's only on the rollfim versions? I rated the Acros at 80 ASA for Rodinal 1+50 and the negs were good.
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Got COMPUTERISED at last and now Digitised but FILM still RULES!
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zx9
old hand
Reged: 22/06/2007
Posts: 907
Loc: London
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Quote:
Quote:
it's the anti-halation dye added to the back of the film intended to increase contrast by stopping light been reflected back from / by the substrate. In some films it forms a dark red cloud when combined with the thiosulphate in the fixer.
Hmm - why does it not come off in the pre-soak (if you use one) or in the developer? I use a pre-soak (water with a couple of drops of wetting agent) and am quite used to seeing that being dirty grey when poured out. But the reason for the pre-soak is to ensure that the developer acts evenly without having to agitate too much, which can spoil the acutance properties of the soup.
Is there a bit of emulsion under a sticky label (used to attach the spool perhaps) which is only getting wet at the end of the process?
Well the Google bots have been on the forum, I just googled for it and got my own post as item 3. Looking around it seems to have cropped up on several forums over the years. General opinion seems to be depending on film type some are water soluble and will start to disolve in a pre wash, others need the fixer to form a soluble compound and hence only wash out in the final wash. You could take a leader from several types of film and process in daylight and compare when either the liquid tinges red/brown of when the film base stops been pinkish.
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ZX9 (Keith)
My Flickr Pictures
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StevenJ
newbie
Reged: 25/10/2005
Posts: 19
Loc: Glasgow
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thank you for the explainations. I had never seen it before, so was worried that when I pick up the film tomorrow, I might get a load of blank frames!
I left the negs hanging in a dryer last night, and I'm not back in the club until tomorrow.
I have also never thought of pre-rinsing either, that is something I will consider in future.
thanks
Steven
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taxor
Reged: 09/07/2004
Posts: 555
Loc: Lancaster, UK
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Anti-halation layers in ilford 35mm films generally don't wash out in a pre-rinse (something about the way they're layered on the emulsion, I think), whereas they do with 120 films. One way to reduce that pinky/purplish tint on your negs is to immerse the negs in washaid for a brief while and then wash as normal.
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"I wanna hold your gland". Lemming & McCartney
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John_K
addict
Reged: 03/09/2006
Posts: 560
Loc: North Yorks
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I think you may find the pink cloud will change after a while and the fixer will return to its normal clear state.
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Benchmark
Is it safe?
Reged: 12/07/2005
Posts: 2932
Loc: Sedgefield, Co Durham
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I have seen similar effects when final washing both (120) Velvia and Kodak Portra films, but it doesn't seem to do any harm. Given the complex nature of film emulsions it is inevitable that something will be water soluble enough to show up in the final wash.
OTOH I tried pre-washing Portra on one occasion, and the wash water came out thick and green.  It didn't seem to do much good for the colour balance either. 
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Nigel CRIPN and Bar
Beware of the Dark Slide
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apochromatic
newbie
Reged: 06/04/2008
Posts: 8
Loc: UK
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It may be the anti-halation layer but most modern T-grain type films show this staining to some extent. Make sure your fix is fresh and the wash water is also warm enough as tap water is extremely cold at this time of year. Here's a bit from the Kodak site
With KODAK PROFESSIONAL T-MAX Films,
fixer will be exhausted more rapidly than with other films.
If negatives show a magenta (pink) stain after fixing, fixer
may be near exhaustion, or fixing time is too short. If the stain
is pronounced and irregular, refix the film in fresh fixer.
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DaveS
enthusiast
Reged: 22/06/2007
Posts: 211
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I thought the pink colour was from un-discharged sensitising dye, eg erythrosine. I've seen it more in T-Grain films eg Delta than "Old Fashioned" films such as FP4+ and Pan-F.
I've never seen anti-halation dyes come out from 35mm, but all the time from roll and sheet film, usualy blue-green.
IIRC, it is the developer which bleaches anti-halation dye, not the fixer.
Dave
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Terrywoodenpic
A whiff of silicon...
Reged: 21/01/2006
Posts: 273
Loc: Saddleworth UK
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I started my photography using glass plates. In those days the antihalation coating was often thick enough to feel on the back of the plate.
all films that have such a coating ( and there have been some without) have the coating washed away during prewash or processing... it is neutral in as far as its effect on processing is concerned, so never does any harm.
Most people simply don't notice it, and sometimes the chemical is such the the colour disappears during the process.
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63 happy photo years from amateur to professional and back to amateur
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