Re: Paper negatives (Re: Tricolor gum, order of layers)

[Loris Medici <mail@loris.medici.name>]

Thanks much, I like the cyanotype very much. The gum also is lovely / very
sentimental (both subject + technique). Can't say the same thing about the
casein print though - it looks like a screenprint; very opaque, looks like
made with spot channels, poor tonality... Probably because of acrylic
paint + hazy casein...??? Is it that image particularty or a general
property of all acrylic paint + casein colloid images?

Thanks for sharing these. Take your time about the exposure test, I'm sure
it will be helpful to us if you can make it...

Regards,
Loris.


6 Ekim 2008, Pazartesi, 7:56 pm tarihinde, Guido Ceuppens yazmış:
> 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:
> http://home.versateladsl.be/vt6100419/cyanotype
>
> a gumprint:
> http://home.versateladsl.be/vt6100419/gum
>
> and a caseine print:
> http://home.versateladsl.be/vt6100419/cas
>
> Guido
>
>
> 2008/10/6 Loris Medici <mail@loris.medici.name>:
>> 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
>> more...)
>>
>> Regards,
>> Loris.
>>
>>
>> 6 Ekim 2008, Pazartesi, 2:48 pm tarihinde, Guido Ceuppens yazmış:
>>> Loris,
>>> 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.
>>>
>>> Greetings,
>>> Guido
>>>
>>>
>>> 2008/10/6 Loris Medici <mail@loris.medici.name>:
>>>> 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
>>>> very
>>>> little and too much!?
>>>>
>>>> Regards,
>>>> Loris.
>>>>
>>>>
>>>> 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.
>>
>>
>