Hi Graeme,
Using a UV filter (or the M2 measurement mode) does not make the
FWA/OBA-related problems go away. It is just a simple way of “ignoring” their
presence.
The lighting industry by laying UV to rest has already depracated the
FWAs/OBAs. None of the recent LED light sources have a UV component. Even the
Violet Chip, Red, Green, Blue Phosphor LEDs start emitting from 405 nm, while
blue-chip LEDs start from around 430 nm).
IMHO, until the day paper industry replaces these chemicals with
non-fluorescent white pigments, the best practice would be to “ignore” them by
using the M2 mode, if and when you cannot “avoid” the use of high-OBA papers.
You can always grab M1 data along the M2 simultaneously, if you want to do
on-screen or on-paper simulations of the final print under ISO
3664:2009-compliant lighting, which no one uses to consume the printed image.
There is nothing accidental about why M2 measurement mode returns a balanced
dataset, which in turn creates an ICC profile that produces a full-body yellow
channel. And there is nothing accidental about why M1 measurement mode always
grabs a dataset, from an OBA-rich paper, that always knocks down yellow in all
colors including rich grays.
The printing industry has already lost to much time and energy on trying to
solve a problem that has already become part of history.
Best,
Refik Telhan
On 17.12.2019 01:13, "Graeme Gill" <argyllcms-bounce@xxxxxxxxxxxxx on behalf
of graeme@xxxxxxxxxxxxx> wrote:
Alan Goldhammer (Redacted sender agoldhammer for DMARC) wrote:
> If you want Chromix results you need to get a spectro that supports M3
meaurements. I
> don’t believe that Argyll supports this at present and you would need to
buy an
> instrument for Graeme as well or use some other software.
You can do this if you have access to a spectroscan. Of course you can also
import measurements from other instruments into Argyll using txt2ti3
<http://www.argyllcms.com/doc/txt2ti3.html>.
[ As far as I'm concerned, "Polarized measurements makes shadow detail
better" is in the same category of myth as "Using a UV filter makes
FWA/OBE problems go away". It might do so sometimes by accident, but
reality is more complex than that, and ultimately you are better off
understand what's actually going on rather than depending on random
magic. ]
Cheers,
Graeme Gill.
