Re: Chrysotypes and humidity

[Eric Neilsen <e.neilsen@worldnet.att.net>]

Cor, i use a wooden enclosure ( box) that has a room humidifier sitting 
in it.  The humidifier has a trhree speed fan and a reostat for 
adjusting humidity.  I also use it for platinum printing with 
traditional as well as ammoinum based chemistry.

EJ Neilsen

Lukas Werth wrote:

>At 11:45 14.08.01 +0200, you wrote:
>
>>Last weekedn I gave chrysotype printing a try, using the protocol of
>>Tony McLean had genereously send to this list in 1999.
>>
>>Ther first attempts worked quite nice, the only problem beeing the
>>humidity. It seems that Chrysotypes are very sensitive to humidity (just
>>as Ziatypes), and it happens thta the colour scheme which intersts me
>>most: maroon/purple/blue only "happens" when the humidity is around 50%,
>>not around 95% as it is currently in Holland... When drying with forced
>>air I could shift the colour schem a bit from black/grey/bleu towards
>>violet/blue., but I am not there yet.
>>
>>Do people have experience with humidity chambers? I know that a chamber
>>with beaker of stuarated CaCl2 should have a humidity of around 35% or
>>so.
>>
>>I am wondering: how long would it take for a coated Chrysotype to reach
>>this rel. hum. from say 80 to 35%?
>>
>>Would it help to have the paper before coating as dry as possible? (even
>>heat it?)
>>
>>Cor
>>
>
>
>Cor,
>
>I have cat litter trays with saturated solutions in them for humidity
>control. Ammonium chloride for 85%, calcium nitrate for 65%, calcium
>chloride in powder form ca. 10%, in sat. sol. ca. 40-50%(?), all ideally 20
>C, which means for me room temperature. The paper is taped on the lid (a
>laminated fiber sheet). I usually dry the paper first over calcium chloride
>powder, and then bring it to the desired humidity over the other solution
>(over each between 1/2 h and 1 h).
>
>Lukas
>
>