Re: FWA in a ColorChecker SG!?
Re: FWA in a ColorChecker SG!?
- Subject: Re: FWA in a ColorChecker SG!?
- From: Ernst Dinkla <email@hidden>
- Date: Fri, 28 Aug 2015 10:47:13 +0200
The ColorMunki only measures from 430 to 730 Nm in reflective mode and
copies the 430 measurement down to 380 Nm, I guess with the X-rite drivers.
The sensor goes to 400 Nm for emitted light so one would expect the LED to
be UV-cut. Any UV absorption + OBA effect shown in results must be
extrapolated from 430-730 Nm downwards.
Old information from that ArgyllCMS list:
http://www.freelists.org/post/argyllcms/ColorMunki-or-i1pro-for-CM,8
Met vriendelijke groet, Ernst
Dinkla Grafische Techniek
Quad, piëzografie, giclée
www.pigment-print.com
On Fri, Aug 28, 2015 at 5:08 AM, Ben Goren <email@hidden> wrote:
> On Aug 27, 2015, at 4:23 PM, Ben Goren <email@hidden> wrote:
>
> > The GCATS file
>
> Cancel red alert, as they say.
>
> Turns out the XYZ and Lab values were calculated using a spectral
> measurement of a low-CRI fluorescent lamp as the reference instead of D50,
> and the measurements below 420 nm apparently have no bearing on reality.
> Re-calculating the absolute values with D50 gives a very reasonable Lab
> 96.69498 -0.854171 0.157998, and ignoring values from 430nm and bluer has
> reflectivity varying only from 90.4% - 92.7%.
>
> In other words, it was a number of completely unrelated coinciding unusual
> things conspiring to mimic the appearance of FWA in the chart, despite
> there being not even the slightest drop of FWA present.
>
> ``We apologize for the inconvenience.''
>
> b&
>
> _______________________________________________
> Do not post admin requests to the list. They will be ignored.
> Colorsync-users mailing list (email@hidden)
> Help/Unsubscribe/Update your Subscription:
>
>
> This email sent to email@hidden
>
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden