Is there any visable loss in print sharpness with a sheet of mylar between the POP and the negative? How thin a sheet if mylar can you get?
Originally Posted by Guillaume Zuili
I don't know Michael. I have been so upset by that lost neg that I didn't print yet with POP. Mourning I guess...
Selenium -1-30 or 1-50 gives a milk chocolate tone. 2-3 minutes in the toner. But, you need to fix it before toning in selenium.
Here is my process.
Expose the print until it is way over exposed. I'm talking really cooked.
Double fix in sodium thyosulphate where it will bleach a lot, this is why you cook the hell out of it.
Put it in the selenium with constant agitation. I have gotten funny lines if I just let it sit.
Really easy, but a bit unpredictable. The brown and white images in my gallery were done this way.
Never had an issue with ruining a negative.
Technological society has succeeded in multiplying the opportunities for pleasure, but it has great difficulty in generating joy. Pope Paul VI
So, I think the "greats" were true to their visions, once their visions no longer sucked. Ralph Barker 12/2004
If you are printing outdoors using the sun, I'd recommend using the mylar. There can be a lot of heat buildup inside the frame and you can get some of the neg sticking to the paper when things go wrong. Also, the humidity might have an effect on the bonding between paper and neg. From experience, I've learned to use mylar if I care about the negative.
Where does a person get mylar of a suitable size and thickness?
Originally Posted by rrankin
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Art supply stores, for overlays. I bought a pack some 10 years ago and am still less than half way through it, despite using some sheets for other things. There is no detectable loss of sharpness.
Originally Posted by Chazzy
Last edited by Roger Hicks; 09-21-2007 at 12:58 PM. Click to view previous post history.
Reason: Stores not sores, but then again...
not much experience toning with gold, but I've done a fair amount in a platinum toner. it works in an acid environment, so mix it with citric acid or hydrochloric... etc. I believed Stieglitz used it with nitric.
It's incredibly easy to get the paper's color to shift toward neutral without loosing d-max in platinum (which I found happening when pushing for cooler tones in gold). Once you get it toward neutral, further toning will bring in the colder colors... then, some more toning will give you warm highlights and upper midtones; extended time in platinum does that, why.. I don't know.
Contrary to things I've read here, platinum was about $5 cheaper than gold per gram a couple months ago when I last bought it. I went through artcraft chemicals.
You can also get green colors when using an aged thiosufite fixing bath. Just plain thiosufite used to the point where it becomes cloudy. (Of course I wouldn't trust that fixer to make the print permanent, so I follow it with two fresh baths.) I won't turn green immediately, so leave it in there for a while. Before it gets green it moves through a yellowish hue, so pull it whenever you're happy. Print heavy, all this fixing bleaches.
I was trying a whole shitload of papers after azo was discontinued and ended up here with POP. It's very finnicky and never 100% repeatable (in my darkroom) but when it works, which is quite often, there's really no comparison between this and azo. I wish I had been using it since I began photographing. This is to azo, what azo was to VC papers (of course you need to have the right negative to find that out. Many of my negs geared toward azo 2 print better on POP).
A good place to start is 15ml of a .2% solution potassiumchloroplatinate mixed with 3 grams citric acid in 500ml of water. Add another 5ml of the platinum solution per print.
Remember print heavy, at least until you start to see bronzing in the shadows. When you prerinse the paper before the toner, don't leave it in the water for too long, just until you see the silver has stopped leaking out. Too long can give you a weak print.
Hope this helps. any questions feel free to call 267.772.0827
Also, I never use mylar or anything else between the emulsions. I once printed a negative upside down, (base side of the neg toward emulsion of the paper) and saw a huge difference in sharpness; don't know anything about the mylar. I live in humid south jersey, and have never ruined any negatives, even on days in the 90's. Not saying it'll never happen, but it hasn't yet.
Not having seen your POP prints Joe, can you attain the typical blacks and white that Azo can produce consistently or is the coloration dark purple? The ability to get POP in 11x4 and larger sizes could get me going in this direction. What are you using as a UV light souce? A contact printing frame with springs or a vacuum frame?
Originally Posted by joefreeman
Thanks all. That's quite an endorsement, Joe. Do you have a link to some of your POP prints? I'm also curious about your light source, specifically, have you used a metal halide or mercury vapor bulb?