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01-09-2008, 10:19 AM
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#11 |
Join Date: Mar 2005 Location: London, UK
Posts: 1,000
|  Platinum/ Palladium – My Printing Process
There is nothing quite like the glow of a genuine platinum print: it is simultaneously gentle and powerful, it is subtle yet rich and luxurious, and it has a physical presence like no other print medium.
Getting started with Platinum/Palladium (Pt/Pd) printing is easy – buy a kit,...
Last edited by Ian Leake; 01-09-2008 at 02:36 PM.
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Yes, thanks Scott. That's a good part 1 - I look forward to the next one | | | | |
Hi Ian,
I have been reading your's and Scott's article about Pt/Pd printing with much interest. Thanks for writing. However, both articles raised a few simple questions that I hope you or Scott are able to answer:
- Although it's not specifically mentioned in either of these articles, since the Pt/Pd process is mostly UV sensitive, am I right that you can, and do, coat and work under normal light conditions (so not save light but a normal light bulb)?
- And how big is the risk of fogging paper, for example through an (open) window by strong (UV rich) sun light?
- What development times can be expected / are roughly necessary if I want to try developing under sunlight conditions / outside? (I realise this is very much depended on all kinds of variables, like weather, season, and position on the globe)
- Is it practical at all, to use sunlight?
- How long can all of the chemicals be kept? Considering the high price, it would be a major waist of money have to throw away Pt/Pd chemicals, because I have not used them up in time. Can they be kept for months on end in their original concentrated form? And working solutions?
- And lastly: how about dodging and burning in? Since this is a contact printing process using UV light boxes, I guesse d&b is out of the question? This also implies negatives must be more or less "perfect" in terms of contrast (so no areas requiring major work)?
- On the other hand, since it is contact printing, the printing process itself is likely much more sensitive, and will pick up both highlight and shadow detail that would be lost in silver enlarging printing? Is this right, so there is simply inherently much less need for dodging and burning?
Thanks for any info!
Marco | |
Last edited by Marco B; 02-02-2008 at 04:59 AM.
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Hi Marco – I’ve tried to answer your questions below… Quote:
Originally Posted by Marco B  Although it's not specifically mentioned in either of these articles, since the Pt/Pd process is mostly UV sensitive, am I right that you can, and do, coat and work under normal light conditions (so not save light but a normal light bulb)? | Yes, I have a ordinary tungsten bulb in my darkroom which is always on when I’m printing. I try to avoid direct strong artificial light and any daylight to minimise risk of fogging. A simple test to see if you’re getting fogging is to coat two sheets one in the dark and one under normal working conditions. Develop them without exposing to a UV source and see if you can tell the difference. Quote:
Originally Posted by Marco B And how big is the risk of fogging paper, for example through an (open) window by strong (UV rich) sun light? | The simple answer is don’t allow daylight into your workroom because it’s hard to tell how much UV is bouncing around. Otherwise try the fogging test above. Quote:
Originally Posted by Marco B What development times can be expected / are roughly necessary if I want to try developing under sunlight conditions / outside? (I realise this is very much depended on all kinds of variables, like weather, season, and position on the globe) | Do you mean development time or exposure time? The former is one to two minutes depending on paper surface, absorbency, etc. The later entirely depends on your negatives and strength your of UV source. My starting time is always 3 minutes but that’s meaningless unless you’re going to use my lightbox with the same tubes. Quote:
Originally Posted by Marco B Is it practical at all, to use sunlight? | Yes, many past photographers used sunlight. But it’s a lot less predictable and I’d recommend buying or building an artificial UV source. Quote:
Originally Posted by Marco B How long can all of the chemicals be kept? Considering the high price, it would be a major waist of money have to throw away Pt/Pd chemicals, because I have not used them up in time. Can they be kept for months on end in their original concentrated form? And working solutions? | Powdered chemicals last forever (or as close to forever as you’ll notice); likewise Pt/Pd solutions. Ferric Oxalate in solution should comfortably last a couple of months (depending on storage conditions). I rarely have Ferric Oxalate in solution for longer than a two or three weeks so I can't say for sure when it goes off (and it's very cheap so I'd rather throw it away rather than risk using it if it's a bit old). Potassium Oxalate lasts in solution until it evaporates or is carried off by the paper into the clearing process. Typically 600cc lasts me perhaps 12 or so prints. Potassium Dichromate lasts ages (I think). Quote:
Originally Posted by Marco B And lastly: how about dodging and burning in? Since this is a contact printing process using UV light boxes, I guesse d&b is out of the question? This also implies negatives must be more or less "perfect" in terms of contrast (so no areas requiring major work)?
On the other hand, since it is contact printing, the printing process itself is likely much more sensitive, and will pick up both highlight and shadow detail that would be lost in silver enlarging printing? Is this right, so there is simply inherently much less need for dodging and burning? | I’ve never needed to dodge or burn a print. Pt/Pd copes with highlights very, very well. That being said I work indoors under artificial light so I never have unusual lighting conditions  There’s no reason not to dodge and burn if you want to, but remember that there’s loads of UV flying around so wear serious eye protection (your retina have no pain nerves so you only find out that you’ve got sunburn when they stop working…). Given you’re using sheet film it makes sense to learn the zone system and develop your negatives properly rather than dodge and burn extensively.
I hope that helps you. And good luck printing. | | | | |
Thanks Ian, this answers it all. And yes, I intended to write "exposure" but some weird mind twist made me end up with "development"...  | | | | |
Your welcome Marco. Development time is an interesting question though. Many describe Pt/Pd as developing "instantly" but consensus seems to be to leave the paper in the developer for two minutes. I don't think the precise development time matters much (I haven't seen any differences in the prints anyway) - the important thing is that sufficient developer soaks into the paper to develop the coating that's down in the fibres but not so much that you carry to much developer over into the next bath (and waste it). | | | | |
Hi Ian,
One more question came up after reading and pondering all info:
- How long can a coated, but non exposed & developed, paper be kept? Can one "store" coated papers for future usage? So let's say I coat 10 sheets, but only print and develop 4, can I store the other coated and sensitized sheets for any usable length of times (e.g. a few weeks?). And will this effect image quality? | | | | |
I try to use all coated sheets on the day I prepare them. I have in the past used sheets that have been in a box for over a week and not noticed any problems, but I've also read things that imply it's best to use fresh paper (though I can't remember the source, what supposed to go wrong, and haven't tested this). Not a full answer, but I hope it helps a bit Marco. | | | | |
Yes, that is helpful. Good to know that it is possible to store papers for at least some practical time, as it not always predictable how much time is needed to print a certain image, nor how much paper will be used, so any left over paper can than be used for a future printing session on another day. | | | | |
Quote:
Originally Posted by Ian Leake I try to use all coated sheets on the day I prepare them. I have in the past used sheets that have been in a box for over a week and not noticed any problems, but I've also read things that imply it's best to use fresh paper (though I can't remember the source, what supposed to go wrong, and haven't tested this). Not a full answer, but I hope it helps a bit Marco. | The biggest problem with storing pre-coated papers is desiccation or drying out of the paper. If you want to store paper long-term (more than a couple days), you need to completely de-hydrate it and store it in arid conditions (ideally in an airtight container). Otherwise, the partial humidity in the paper will cause changes in the sensitivity and responsiveness of the emulsion. If you do completely desiccate a pre-coated paper and store it in an airtight container, you will need to thoroughly re-humidify before printing. Frankly, this is a pain in the butt and not easy to do properly. Best to just coat as you go. | | | | |
Thanks Scott,
I will definitely try to coat as I go, but it is good to know the possibilities, limitations and prerequisites of any new process you're learning. | | | | Article Tools | | | | Display Modes |  Linear Mode | |
