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barnacle
6-Jul-2016, 12:29
When I develop Adox, the pre-dev wash comes out deep blue and the developer comes out red.

When I develop Agfa Green x-ray, the wash comes out pink and the developer comes out blue.

The Agfa film is pink before exposure and blue after it's developed...

I'm sure it's doing it just to annoy me!

Neil

Jac@stafford.net
6-Jul-2016, 13:16
This will seem counter-intuitive, but after a post-fixing rinse put it back into any developer, agitate well and wash. The tint left on the film should be gone.

Randy Moe
6-Jul-2016, 13:18
X-Ray film?

Is different.

DrTang
6-Jul-2016, 13:21
tmax - the developer looks like grape rush when you dump it out


I told my kid I develop film in grape crush and showed he when I dumped it out

she didn't buy it..but she knew to be wary of what I said by age 3

FredrickSummers
6-Jul-2016, 14:19
tmax - the developer looks like grape rush when you dump it out


I told my kid I develop film in grape crush and showed he when I dumped it out

she didn't buy it..but she knew to be wary of what I said by age 3

I think that's a Kodak thing. The Ektar and portra I have done c-41 all come out with the same color from the presoak.


Sent from my iPhone using Tapatalk

Bruce Watson
6-Jul-2016, 16:01
When I develop Adox, the pre-dev wash comes out deep blue and the developer comes out red.

When I develop Agfa Green x-ray, the wash comes out pink and the developer comes out blue.

The Agfa film is pink before exposure and blue after it's developed...

Mostly these are the sensitizing dyes. It's how you turn an orthochromatic emulsion into a panchromatic emulsion (https://en.wikipedia.org/wiki/Panchromatic_film).

If you do a prewash, it will carry a bunch of sensitizing dye with it when you pour it out. And you haven't even started to develop the film yet. When I do this with TMY-2, I get purple. At the end of processing the film is usually slightly purple-pink.

The color is basically meaningless. If you don't like your film color when you're done, give the film a few minutes in sunlight. The UV will generally kill off the color for you. But it's not necessary. You can print right through it in the darkroom (has no effect on the print). Similarly, you can scan right through it.

seezee
6-Jul-2016, 16:27
The color is basically meaningless. If you don't like your film color when you're done, give the film a few minutes in sunlight. The UV will generally kill off the color for you. But it's not necessary. You can print right through it in the darkroom (has no effect on the print). Similarly, you can scan right through it.

So it doesn't affect variable contrast paper?

Jim Noel
6-Jul-2016, 17:48
Mostly these are the sensitizing dyes. It's how you turn an orthochromatic emulsion into a panchromatic emulsion (https://en.wikipedia.org/wiki/Panchromatic_film).

If you do a prewash, it will carry a bunch of sensitizing dye with it when you pour it out. And you haven't even started to develop the film yet. When I do this with TMY-2, I get purple. At the end of processing the film is usually slightly purple-pink.

The color is basically meaningless. If you don't like your film color when you're done, give the film a few minutes in sunlight. The UV will generally kill off the color for you. But it's not necessary. You can print right through it in the darkroom (has no effect on the print). Similarly, you can scan right through it.

More likely the anti-halation backing in the pre-wash, and possibly that plus some sensitizing dye in the developer and afterward.

barnacle
6-Jul-2016, 22:40
The blue from Adox wash is the anti-halation layer; I've seen it still there on odd occasions when I've had a film stick to the bottom of the tray.
The blue on the x-ray looks to be part of the film substrate; it's constant irrespective of development times etc, completely uniform. Though no problem to scan through.
And I suspect that Bruce is right regarding sensitizing dyes; no reason for them to be the same colour between films or even at different stages in processing. The x-ray film is of course coated on both sides, so you can't see the substrate without removing some emulsion.

Neil

seezee
7-Jul-2016, 13:36
The blue on the x-ray looks to be part of the film substrate; it's constant irrespective of development times etc, completely uniform.

All x-ray film, AFAIK, is on a blue polyester substrate.

Randy Moe
7-Jul-2016, 14:23
All x-ray film, AFAIK, is on a blue polyester substrate.

I think it started out as normal film on a clear base, but blue was chosen to ease eye strain for Medical types gazing at very important detail all day on bright light boxes.

It will not wash out, hence my earlier comment, 'X-Ray is different!"

StoneNYC
7-Jul-2016, 15:34
It's just the anti halation backing coming out... Some films have them, some don't, if you don't pre-wash long enough or dump and fill enough times with a few pre wash water bath then you're going to get different colors from different films, it's not any of the developers Rodinal or any other, it's the anti halation backing differences between films.

Jim Noel
7-Jul-2016, 15:37
The blue from Adox wash is the anti-halation layer; I've seen it still there on odd occasions when I've had a film stick to the bottom of the tray.
The blue on the x-ray looks to be part of the film substrate; it's constant irrespective of development times etc, completely uniform. Though no problem to scan through.
And I suspect that Bruce is right regarding sensitizing dyes; no reason for them to be the same colour between films or even at different stages in processing. The x-ray film is of course coated on both sides, so you can't see the substrate without removing some emulsion.

Neil

Not all x-ray film is coated on both sides. The film designed for mammography is usually single sided.

Bruce Watson
8-Jul-2016, 09:15
So it doesn't affect variable contrast paper?

When I called Kodak and asked that very question, they said no.