Re: HC110 or Pyrocat HD for FP4
Quote:
Originally Posted by
Ken Lee
What is the benefit of a mildly acid stop bath ? Is it to arrest development more instantaneously and completely ?
It does that, though film usually goes through the water bath and into the fixer rapidly enough that it doesn't matter.
As per Sandy's experience, the stop bath protects the fixer from the alkalinity of the developer. It's more important in printing, as paper developers are much stronger, more work passes through the solutions, and if you're using fiber-based paper, more developer follows a given sized piece of paper as it's absorbed into the paper.
I use a stop bath in printing, but not with film, just a quick dip in the water there...
Re: HC110 or Pyrocat HD for FP4
I just tried adding 1/2 of the recommended 10 grams per liter, with some 4x5 sheets of TMY.
As predicted, the negatives developed faster. Using my IR viewing device for Development By Inspection, I yanked the film around 25% early.
When the film emerged from the fixer, it still had a Magenta cast - but as soon as I rinsed it a bit, all the Magenta dye went down the drain. Wow !
I've never seen Pyrocat negatives like this. They look as though I used any of the other "plain vanilla" developers: No magenta color cast at all. I'm amazed.
Re: HC110 or Pyrocat HD for FP4
Hey Ken, how was image stain?
Re: HC110 or Pyrocat HD for FP4
The color of the stain is slightly brown. But just barely. Not as brown as before. Here's one:
Re: HC110 or Pyrocat HD for FP4
Could Sodium Sulfite be added to Part A, or must it be added to the mixed developer, just prior to use ?
Add too much it disappears and you have a tanning but non-staining developer.
Aren't these the same ? What's the difference ?
Re: HC110 or Pyrocat HD for FP4
Tanning is a hardening of the emulsion, staining is a physical dye in addition to the silver image.
Ian
Re: HC110 or Pyrocat HD for FP4
I've been processing FP4+ using Prescysol which apparently is very similar to Pyrocat HD.
I've been using the standard 1+5+100 mixture, but only using 106ml for 4 sheets of 4x5 film in an Orbital processor and I'm wondering if I am using too little developer. I don't really want to use much more liquid, so if I double the A & B concentrations (giving 2+10+100), would that give me a similar result to using double the standard solution? What does the water part of the solution do, other than providing a means of getting the A & B solutions to the emulsion?
This was a bit of a catalogue of errors, but it's what I've got so far:
http://farm5.static.flickr.com/4046/...2eaa7c22ac.jpg
Orchid. Arca-Swiss Pro1 Symmar-S 210 @f5.6. FP4+ Prescysol
Re: HC110 or Pyrocat HD for FP4
Quote:
Originally Posted by
sanking
It works because the stain with Pyrocat is very sensitive to sodium sulfite. Add too much it disappears and you have a tanning but non-staining developer.
How much? I used to have a record of this from tests but can not find the notes. However, I am pretty sure that the addition of 10 grams per liter of sulfite to a working solution would be enough to kill the stain.
Is the sulfite going to kill the stain only if you add it to the developer? I'm asking this because I'm using a simple home-made thiosulfate fixer, which contains 30g of sodium sulfite per liter. So far I've only developed one film in Pyrocat, and the stain is definitely there, though given my total lack of experience with Pyrocat I cannot tell if the stain level is normal or not. :confused:
Should I worry about the sulfite content of my fixer?
Thanks.
Re: HC110 or Pyrocat HD for FP4
Re: HC110 or Pyrocat HD for FP4
Quote:
Originally Posted by
Ken Lee
Could Sodium Sulfite be added to Part A, or must it be added to the mixed developer, just prior to use ?
Add too much it disappears and you have a tanning but non-staining developer.
Aren't these the same ? What's the difference ?
If you add the sulfite to part A well before use the developer won't last long at all.
I started using sulfite to remove stain because I wanted to print on VC paper and didn't always like the slight tonal shifting effect that the stain gave. For some scenes it wasn't an issue but for photos of people I found it ugly. YMMV.
I'm not sure there is anything to gain by removing the stain unless you're printing on VC paper. For scanning it does not matter at all. But its real easy to add just before use and you can choose each time depending on your purpose at the moment.