Luminous Landscape Forum

Raw & Post Processing, Printing => Colour Management => Topic started by: rabanito on April 08, 2019, 06:22:37 am

Title: Do calibration "solutions" age with Time?
Post by: rabanito on April 08, 2019, 06:22:37 am
For my monitor I'm using a Spyder 3.  I re-calibrate every 3 months
Everything in my workflow is working to my satisfaction (admittedly to my modest pretensions) including printing, which is my end-target.

Now out of curiosity.
Is it possible that calibrating devices change over time, giving results different from those obtained when they where young?
And that this happens in a subtle way, not easy to detect but having (increasingly worsening) consequences on the end results?
Is it necessary or wise, after some time, to exchange those devices for newer ones?

Title: Re: Do calibration "solutions" age with Time?
Post by: TonyW on April 08, 2019, 07:38:05 am
For my monitor I'm using a Spyder 3.  I re-calibrate every 3

Now out of curiosity.
Is it possible that calibrating devices change over time, giving results different from those obtained when they where young?
And that this happens in a subtle way, not easy to detect but having (increasingly worsening) consequences on the end results?
Is it necessary or wise, after some time, to exchange those devices for newer ones?
I believe that it is likely that calibration devices will change over time, filters fade (less so dichroic), electronics age etc.  The effects likely to be subtle at first and not noticeable. 

But if you have a calibration device that calibrates your calibration device to a known standard then changes will be accounted for - still that device will also need checking against known calibration points and replaced every so often = calibration hell and uncertainty fir some.  :o 8) ;D

As long as your device is consistently producing what you require e.g. accurate for print to monitor match then perhaps no worry?

You may find that an upgrade needed for reasons other than equipment aging.  Perhaps you will replace your monitor with wide gamut and find that Spyder 3 is not up to the task. This was the case for me and I jumped to the X Rite i1Display by all accounts a superior system. 
Title: Re: Do calibration "solutions" age with Time?
Post by: rabanito on April 08, 2019, 11:55:27 am

As long as your device is consistently producing what you require e.g. accurate for print to monitor match then perhaps no worry?

Thanks Tony
You're right.
But I was thinking of what happens if I detect inconsistencies.


Is it the monitor, is it the calibration device, is it a different batch of paper, is it the printer, is it....
For an inexperienced  amateur as I am it could be confusing.
"The horror, the horror" as Kurtz would say  ;D
So I try to check one item at a time
Title: Re: Do calibration "solutions" age with Time?
Post by: nirpat89 on April 09, 2019, 05:47:38 pm
My ColorMunki does self-calibration every time it is turned on for use.  Shouldn't that take care of any drift that might be occurring over time.
Title: Re: Do calibration "solutions" age with Time?
Post by: DP on April 09, 2019, 07:48:16 pm
I'm using a Spyder 3.

obligatory horror story about DataColor = https://www.drycreekphoto.com/Learn/Calibration/MonitorCalibrationHardware.html

PS: now may be v5 is not that bad, but ...


Title: Re: Do calibration "solutions" age with Time?
Post by: digitaldog on April 09, 2019, 09:11:29 pm
obligatory horror story about DataColor = https://www.drycreekphoto.com/Learn/Calibration/MonitorCalibrationHardware.html

PS: now may be v5 is not that bad, but ...
But this:
https://forum2.luminous-landscape.com/index.php?topic=129027.new;topicseen#new
Title: Re: Do calibration "solutions" age with Time?
Post by: rabanito on April 10, 2019, 10:56:47 am
Thank you, interesting articles  :)
Title: Re: Do calibration "solutions" age with Time?
Post by: GWGill on April 10, 2019, 08:13:28 pm
My ColorMunki does self-calibration every time it is turned on for use.  Shouldn't that take care of any drift that might be occurring over time.
That calibrates the reflectance mode.

The i1pro 2 (spectrometer) does calibrate for wavelength drift, but as in all metrology, calibrating or verifying a measuring device depends on having some more trustworthy reference available. In the ColorMunki and i1pro the reflectance reference is the white calibration target. The assumption is that the white material changes less than the electronics and optics of the instrument. For the i1pro 2 the wavelength reference is a green LED. The assumption is that the LED changes wavelength less than the electronics and optics of the instrument.

None of these popular instruments have effective self calibration for emission measurement. They are calibrated at the factory against higher grade instruments with traceable calibration back to international standards, and then they are on their own, unless they get re-calibrated, which rarely happens for such low cost devices ("low cost" means something like < US$1000. High grade instruments are much more expensive than that).

In practice diffraction grating based spectrometers seem to be pretty stable if they haven't been knocked about or got dirty (i.e. reportedly have consistent readings over years). Same with well made dichroic filter based colorimeters. Colorimeters based on other types of filters ? - not so much.
Title: Re: Do calibration "solutions" age with Time?
Post by: nirpat89 on April 11, 2019, 10:25:35 am
That calibrates the reflectance mode.

The i1pro 2 (spectrometer) does calibrate for wavelength drift, but as in all metrology, calibrating or verifying a measuring device depends on having some more trustworthy reference available. In the ColorMunki and i1pro the reflectance reference is the white calibration target. The assumption is that the white material changes less than the electronics and optics of the instrument. For the i1pro 2 the wavelength reference is a green LED. The assumption is that the LED changes wavelength less than the electronics and optics of the instrument.

None of these popular instruments have effective self calibration for emission measurement. They are calibrated at the factory against higher grade instruments with traceable calibration back to international standards, and then they are on their own, unless they get re-calibrated, which rarely happens for such low cost devices ("low cost" means something like < US$1000. High grade instruments are much more expensive than that).

In practice diffraction grating based spectrometers seem to be pretty stable if they haven't been knocked about or got dirty (i.e. reportedly have consistent readings over years). Same with well made dichroic filter based colorimeters. Colorimeters based on other types of filters ? - not so much.

Thanks GW a bunch, for the complete picture.

:Niranjan.