| I've been really lucky lately, it's been mild here in toronto with above normal humidity. Before coating yesterday, I notice that my coating table was no longer level. This was probably the major culprit ( as I'm using a Puddle Pusher)! The prints turned out much more even with only minor staining (landscapes with paper white skies don't help). I will try your Everclear suggestion Sandy and order some Tween from B&S. Loris mentioned Photoflo in his post. Would this work just as well as Tween? How much would one use per ml of sensitizer? My coating room was just under 50% RH and exposure room was around 35%. So it wasn't outrageously dry. I just sealed my paper in a black plastic photo paper bag for transport between locations, to help keep in moisture.
cheers david
On 22-Dec-06, at 10:29 AM, Sandy King wrote:
I really understand your problem with humidity in Toronto this time of year. Mark Nelson and I did a Pt./Pd. workshop up there a couple of weeks ago and the low humidity was a major problem.
Humidity is important just prior to exposure and during exposure, but if you coat and dry in a humid room and then immediately expose in a room with less humidity you may be ok. But you need to work fast, because a room with very low humidity, say 20% or less, will really suck the moisture out of the paper.
In lieu of Tween you might try a spirt called Everclear, adding just a drop or two per ml of coating solution. Everclear is a pure grain alcohol about 190 proof and I use it from time to time with some papers and it seems to help give a more even coating.
Sandy
At 8:34 AM -0500 12/22/06, david drake wrote: thanks for your replies Loris and Judy. If I can get a hold of some, it seems that Tween 20 is the best plan of action. I also came across some good info on Mike Ware's website in regards to the Argyrotype process: "If there is any 'bleeding' of colloidal silver metal, indicated by a red-brown stain running off dense areas of the image, then the paper fibres are failing to trap the colloidal silver particles, and it is likely that insufficient Tween has been used or the paper is unsuitable"
I have two questions: - I have been attempting to coat the paper in a higher humidity environment (it's very dry up here in canada) and have almost 50% RH, but I am exposing and processing at a different location. Is humidity also important just prior to and at the exposure stage? - Would Photoflo work just as well as Tween? How much Photoflo would one add to the coating solution? Mike Ware includes Tween in his Argyrotype recipe at the amount of .2 cc in 100 cc solution. - any idea where on would find Tween 20 other than ordering from B&S? I'm in Toronto, for anyone reading from this neck of the woods. (oh, I'm sorry, that's three questions :)
Mike Ware's website Argyrotype page: http://72.14.203.104/search?q=cache:gOeGORrqpPcJ:www.mikeware.co.uk/mikeware/Argyrotype_Process.html+Van+dyke+printing+staining+problem&hl=en&ct=clnk&cd=9&client=safari
thanks very much, david
On 21-Dec-06, at 2:56 AM, Loris Medici wrote:
You can try to use some Tween (or Ilfotol or Photoflo) in the coating solution (additionally; try to humify the paper before coating) - it seems you have coating solution absorbtion problems. I also occasionally got bleeding w/ double coated Vandyke but not staining (I mean on a perceptible / disturbing scale). Agitating more vigorously may help too. You can switch to another paper with a better sizing or size before using. (BTW, Sandy can provide you useful information about Stonehenge and iron-silver processes; IIRC, he uses/used that paper extensively for Kallitypes.)
Regards, Loris.
-----Original Message----- From: david drake [mailto:daviddrakephoto@sympatico.ca] Sent: 21 Aralžk 2006 Pers¸embe 06:44 To: alt-photo-process-l@usask.ca Subject: VDB metal bleed in water bath
hello
Processing some VanDykes today, a number of them started 'bleeding' from the masked borders. This bleeding developed into stains. I tried both leaving the print image size down in the initial water bath (with very little agitation) and ,at the same time, not adding citric acid to the water bath. This did work, for the most part . I'm thinking that it was probably the inversion of the print which helped; but, could the citric acid play a part in this problem? If the initial water bath was too acidic could it cause bleediing? I should also say that I was printing on Stonehenge and the paper was double coated. I have found very little information about this staining problem and was hoping that someone might have some answers or at least a better remedy. I also really like the look of stonehenge with palladium toned VDB and am hesitant to switching papers.
thanks david
david drake photography www.daviddrakephotography.com
david drake photography www.daviddrakephotography.com
david drake photography www.daviddrakephotography.com
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