Στις 26/2/2020 6:53 μ.μ., ο John Floren *γραψε:
Ken Hart writes:
On 2/21/20 3:13 PM, John Floren wrote:
Anyone got tips for printing color negatives (Portra 400 120 format, in
this case) on B&W photo paper? I don't have a color enlarger, but I'd
like to make some prints. Thought I ought to poll for suggestions before
I start fooling around wasting paper.
john
It was difficult years ago, and it's probably more difficult now!
First, you don't really need a color enlarger to print on B&W
paper. What you need is some of the long-ago discontinued Kodak
Panalure paper. Panalure paper was sensitive to nearly all colors of
the spectrum, so that color negatives would reproduce better. Standard
B&W paper has low sensitivity in the red area, so the tones are going
to be off.
(If you find someone selling Panalure paper on eBay, it has probably
long ago expired.)
Second, the color mask of color negatives (the overall orange color)
will make the color negative nearly invisible to the b&w paper, so
your exposure times will be long. And color paper has higher contrast
than b&w paper, so you are going to need a high contrast grade. This
will also increase your exposure time.
If you just need a proof print, use a #4 or 5 contrast filter, and an
exposure maybe 6 times as long as usual, and print like any other b&w
negative, being aware that it might not be perfect.
If you need a print with proper tonal rendition, an internegative is
probably your best route. Or a digital solution.
Thanks for the info. I think I *have* printed a color negative on B&W
paper in the past, but as you mention I recall it needing a very long
exposure. I'll fiddle with those contrast filters and see if I have any
luck... it figures that the filters I've got don't really attach to my
Omega D-2, so in the past I've just braced my hand against the lens
carrier and held them in front, which worked surprisingly well for B&W
prints but will probably get tiring if I'm experimenting with long
exposures!
you might think of getting a set of Ilford multigrade filters that have
a special filter tray that screws *on* the lens and it also has a spare
red filter. very useful as my Meopta Axomat II has no filter tray and it
has not the red filter anymore, probably destroyed by its previous user
(now deceased, alas). also check this site in Germany
www.macodirect.de
has an option for English.Although you can't get colour chemicals
through air post anymore due to air safety.
https://www.macodirect.de/labor/papi...ktiv-12-filter
the link I post is in german so choose the English version.it sells for
99 euros.macodirect has the works, it has hundreds of oprions for B&W
paper!even the good ilford multigrade FB.we had a very nice darkroom
shop maybe 500 m from my home but it's closed, alas so everything must
be ordered from Athens!