Re: Paper negatives (Re: Tricolor gum, order of layers)
I will try an exposure comparision between oiled/unoiled paper later
and keep you informed. My light source is a Philips Suntan unit with
10 TLK40W/10R lamps, build-in fan and timer, bought cheaply
second-hand in a garage sale.
Example of a cyanotype print with oiled paper:
and a caseine print:
2008/10/6 Loris Medici <email@example.com>:
> I'm really curious about your exposure times with unoiled negatives,
> thanks for taking the trouble...
> BTW, what light source do you use? Those cyanotype exposures are pretty
> short, I never managed to get the exposure below 8-9 minutes with the most
> transparent media I have on hands. (Ultrafine, w/ Pictorico it's a little
> 6 Ekim 2008, Pazartesi, 2:48 pm tarihinde, Guido Ceuppens yazmış:
>> I can only report on my own findings, other people may work differently:
>> - my cyanotype exposure with an Agfa Scanjet negative : 2 min 30 sec
>> - my cyanotype exposure with an Epson Photo Quality Paper negative,
>> oiled : 7 mins
>> - my gum exposure with an Epson Photo Quality Paper negative, oiled :
>> 2 mins to 3:30 mins
>> - my caseine exposure with an Epson Photo Quality Paper negative,
>> oiled : 40 to 60 secs
>> I never tried exposure with un-oiled Epson Paper. Later tonight I will
>> upload an example.
>> 2008/10/6 Loris Medici <firstname.lastname@example.org>:
>>> Guido have you compared the exposure time with un-oiled negatives? Have
>>> you noticed any mottling and/or unevenness?
>>> Your and Katharine's experience definitely contradicts with what was
>>> reported by Judy and/or the actual writer(s) of the article in Post
>>> Factory Photography - causing confusion on my part.
>>> I have only used baby oil (liquid paraffine) once, and the paper was
>>> different few days later... Maybe there's a huge difference between
>>> little and too much!?
>>> 6 Ekim 2008, Pazartesi, 1:13 pm tarihinde, Guido Ceuppens yazmış:
>>>> I completely agree with Katharine's post: I no longer bother with the
>>>> mylar separation sheets and have used oiled negs after approx. 2 years
>>>> with the same exposure times, the paper feels only slightly greasy.