Re: I don't understand Rodinol...
Quote:
Originally Posted by
seezee
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!"
Re: I don't understand Rodinol...
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.
Re: I don't understand Rodinol...
Quote:
Originally Posted by
barnacle
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.
Re: I don't understand Rodinol...
Quote:
Originally Posted by
seezee
So it doesn't affect variable contrast paper?
When I called Kodak and asked that very question, they said no.
Re: I don't understand Rodinol...
Just a late added note-I did not see anyone using a wash aid such as Edwin 4in1, Heico Permawash, or Orbit bath. Those are the ones I like in order. After fixing, I used to do a rinse of the sheet film basically in and out of water. Next into the wash aid for the time required and into the regular wash. Always clean negs with Tri-X and Tmax, and also Ilford Fp4, Hp5, for my many students and myself.
Hope this is helpful.
Re: I don't understand Rodinol...
Quote:
Originally Posted by
Rod Klukas
Just a late added note-I did not see anyone using a wash aid such as Edwin 4in1, Heico Permawash, or Orbit bath. Those are the ones I like in order. After fixing, I used to do a rinse of the sheet film basically in and out of water. Next into the wash aid for the time required and into the regular wash. Always clean negs with Tri-X and Tmax, and also Ilford Fp4, Hp5, for my many students and myself.
Hope this is helpful.
Me Too Rod. I've always been a Heico Perma Wash guy. I would not feel comfortable with even an extended straight water wash (not saying that straight water wash won't get it done It's just my personal habits as I was introduced to wash aids by my 1st mentor 30+ years) . I use Perma Wash with film and prints and in particular when rinsing FB prints. Plus it cut WAY down on water usage.
Re: I don't understand Rodinol...
Quote:
Originally Posted by
seezee
So it doesn't affect variable contrast paper?
Seems to me the only potential effect on VC paper would be if the color was a variation of magenta.
Re: I don't understand Rodinol...
Yes it does... The contrast layer on MG is blue sensitive, so this allows more blue... (Magenta has blue in it, so adding it cuts green, but adds blue...)
X-ray prints contrasty for many users of MG due to blue base...
Early Tmax RF had a built in contrast filter for Kodak VC papers for it's screwy grade 2 3/4(ish) required filter to print normal... (The Kodak rep told me so in person when he came to the pro lab and I asked about it... ;-)
Steve K
Re: I don't understand Rodinol...
Quote:
Originally Posted by
StoneNYC
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.
Only Ektascan & other single-emulsion x-ray films have anti-halation backing. And they are all on blue polyester substrates.