GREAT
information! Thank you!
pjs
"Light makes photography.
Embrace light. Admire it.
Love it. But above all, know light.
Know it for all you are worth,
and you will know the key to
photography."
George Eastman
-----Original Message-----
From: Daniel V é zina
Cc: nadar1900@...
Subject: [colorvision_group] RE:Sudden loss of accuracy of Datacolor #1005 after 2 years
From: Daniel V é zina
Cc: nadar1900@...
Subject: [colorvision_group] RE:Sudden loss of accuracy of Datacolor #1005 after 2 years
Dont jump in the air too rapidly... Youre trying to read a very dark patch right?
Your readings are:
> 1) 7,99 | -2,91 | 1,26
> 2) 8,25 | -1,29 | -0,9
> 3) 8,11 | -0,85 | -1,1
> 4) 8,29 | -0,22 | -2,13
> 5) 8,00 | -1,47 | 1,28
You said that youre waiting 5-10 seconds between each measurement.
First, when L reach 8 and below, depending on the texture/finish of the media youre trying to profile, it can be difficult for ANY spectro to give a correct reading. Beware of it. Others more expensive spectro could also show sign of weakness in this area.
Spectro are often a bit less accurate for the first reading. When the sensor is cold. So usually, you should start to read your patches sequence this way:
Your read the first 2 patches, then promptly reposition the spectro and the software on the first patch and start to read continuously all patches with less than 5 sec delay between patch.
In your case the delay between the readings is too long. Just for the fun, use the Tools/Measure function, put the spectro on the patch and then read it two time per sec and see if the values swing a lot or not.You should get very constant values.
Now, you will say that it is not written nowhere to proceed this way. Datacolor never said that the first reading is less accurate. Why?
- Because theyre probably not alone in this case.
- Because this
variation is so small that it will change nothing to the resulting
profile. The printed picture will look identical to the
eyes.
Now, if you have some sensitive work to do, you can always proceed like I said. If you want to read a specific patch/object with the Spectro, then simply read the patch rapidly, discard the first 2 values, average the 3 next ones. (which should be near).
If the Spectro cant provide consistent values when used like cited above, then go to buy a new one, or a different one as you wish. But dont expect that a so cheap device (all brands) will last forever and will be as consistent than a far more expensive device costing thousands of $. But my own experience is that the datacolor unit is as good as a far more expensive spectro.
Also others Spectro come with a different software, good luck to find another software in the price range of S3Print that will give you profiles as nice as what you can build with it. Again, more expensive software dont necessary gives you a better profile.
I run a Fine Art Reproduction business and S3Print is my workhorse to make my profiles. I still have to find a competitor in my area that can match my repro quality and color accuracy. Of course the result of a repro job is not just related to a printer profile. But the printers profiles must be good otherwise it will not works
Good luck!
--
Daniel Vézina
Directeur Technique
Les productions Numart Inc.
PQ, Canada
email: numart@videotron.ca
www.numart.ca
La technologie numérique au service de lArt!