Printer Calabrations ?

ThrillaMozilla

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Most of it - it always depends , you would need to get the spectral transmission curves from the glass manufacturer.
I looked up typical coated window glass, and yes, it transmits some UV. You know that is the case because if it didn't transmit some UV, it would block some visible light and would have a prominent visible tint. So I think they all do, except maybe those strongly colored glasses on some office buildings.

EDIT: I was shocked to find out how much UV my windows pass. I thought I had a UV-free environment.

Just wondering if you have ever checked for fluorescence in ink (which could be unintentional). It might be subtle in appearance, but it could have an effect. The OBAs are subtle in appearance, but they have an effect. The ink on my calendar was certainly not intended to be fluorescent, but it is definitely not subtle.
 
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Andreas S

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I also wonder how UV is handled. Is the UV a measured or assumed part of the incident light that is used to calculate the profile? Or what? I'm not sure how to handle this, especially if we're talking about supposedly UV-filtered daylight. At this point I have many more questions than answers.
The UV spectrum is measured with the light. The light sources entire spectrum is then used to calculate the CTT and the CTT is used to calculate the CIR (Color Rendering Index). By using color adaptation formulas like those from von Kreis, Badford or others by using matrices, the spektrum of each patch will be transformed to xyz values by using the CRI. It's a quite exact method now since there are a lot of known matrices now. At the beginning there where only 3 different, now there are dozens. The more matrices are known, the smaller ist the range of light they are used with. that means that the matrice is more accurate for the light.
 

Ink stained Fingers

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I also wonder how UV is handled. Is the UV a measured or assumed part of the incident light that is used to calculate the profile?
Thre are two parts to the question - what type of light is used when doing profile measurements - and which range does the spectro actually read.

'The light source is supposed to emit some UV '- specified in a standard and commented in the KM document

'It mandates that the light source contains UV content and comply with the spectral distribution specified by CIE illuminant D50 '
from https://sensing.konicaminolta.asia/.../What-are-M0M1M2-and-M3-Measurement-Modes.pdf

a reference to the standard with some explanations to the issues with UV are posted here
www5.konicaminolta.eu/en/measuring-instruments/learning-centre/colour-measurement/colour/iso13655-demystified.html
in the bottom part of the document

The spectro itself is not sensitive to UV light, there is a cut off at 380-400 nm wavelength depending on the device, the actual range is specified in the technical data of the resp. device.

All this does not support any special flourorescent inks converting UV light to other colors like green or red etc.
 

ThrillaMozilla

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a reference to the standard with some explanations to the issues with UV are posted here
www5.konicaminolta.eu/en/measuring-instruments/learning-centre/colour-measurement/colour/iso13655-demystified.html
in the bottom part of the document

...All this does not support any special flourorescent inks converting UV light to other colors like green or red etc.
The article does make the statement "This should also provide correct measurements for samples that show fluorescence active in the visible wavelength area (few inks and toners do show this behaviour to some extent)." From the context I assume they mean "a few inks and toners do show this behavior...."

That's what I was afraid of. I am ordering a BLB lamp to check.
 
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