[pure-silver] Re: Ralph Lambrecht / EM10 enlarging meter?
- From: Ryuji Suzuki <rs@xxxxxxxxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx, titrisol@xxxxxxxxx
- Date: Thu, 06 Jan 2005 15:37:23 -0500 (EST)
From: titrisol <titrisol@xxxxxxxxx>
Subject: [pure-silver] Re: Ralph Lambrecht / EM10 enlarging meter?
Date: Thu, 6 Jan 2005 11:56:36 -0800 (PST)
> - Use a grayscale in the negative holder (6x6) then measure the Em10
> setting for 2 or 3 stops. Then print a test with the Kodak Wedge
> and determine exposure for zone 1, 5 and 8 After that since I had
> made a table of +- stops I can determine the times required to
> generate any gray tone for the paper.
I've tried to calibrate EM-10 but it's not that useful...
EM-10 uses CdS as the photosensor, and this cell is sensitive to wide
range of spectrum including safelight. Unless you put a blue-green
filter on the hole, you'll have to shut the safelight when using
EM-10. But then how are you going to deal with contrast filters?
(Fine, my most precious paper is graded.)
With that limitation in mind, calibration can be easily done with an
ordinary incident light meter. With Sekonic L-408 meter set at 100
speed, 2.5 * 2^EV is pretty close to lux. (Note: different light
meters are calibrated differently. I've compared my meter with my
friend's Minolta meter, but it was significantly different. Light
meters are not designed for this purpose anyway, I'm merely suggesting
they can be used this way if you know the meter's calibration.) You
can set an empty neg carrier and change the aperture and/or head
height to create a range of illuminances at which you make a
calibration table for EM-10. Then fit a suitable curve and
interpolate.
But when I'm *mass* printing something, I usually fix exposure time
and change aperture to adjust the illuminance. (Don't use clicks on
the lens) If the negative is exposed rather uniformly, this generally
works very well and EM-10 doesn't need to be calibrated.
--
Ryuji Suzuki
"Keep a good head and always carry a light camera."
=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your
account (the same e-mail address and password you set-up when you subscribed,)
and unsubscribe from there.
Other related posts:
