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Author Topic: QP Card Camera Calibration - works, Camera Profiles don't show in Camera Raw  (Read 18508 times)

Rhossydd

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I tried to order at QP but something went wrong with the VAT number registration.
Were you expecting the VAT to be automatically removed ? It wasn't for me, but it's not enough to be worth bothering about.
I'm just very curious to see how the profiles it delivers compare to the CC24 ones.
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Ernst Dinkla

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Were you expecting the VAT to be automatically removed ? It wasn't for me, but it's not enough to be worth bothering about.
I'm just very curious to see how the profiles it delivers compare to the CC24 ones.

I actually expected that, I had a similar function running before my Canvas Wraps became shareware. The QP purchase went wrong in a typical way, I had the VAT number added and did see that the sum still contained VAT but I thought the extra money would not be something to bother about, then it got stuck at the Paypal side, I guess due to the VAT inconsistencies. Then I tried to create an account first with the VAT number included and I could not get it passed. Then I thought if you have that function it should work and reported that flaw. The QP people at least try to do it correctly. Xara Ltd in the UK, now part of the German company Magix AG, has over the past 20 years never delivered its software (+upgrades) at 0% VAT to companies in Europe. Not just on downloads but also on CDs + manuals through snailmail.


met vriendelijke groeten, Ernst
Shareware too:
330+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
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elolaugesen

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copy of my reply to other discussions...( I know this is against rules etc...  but....)


Sent an email to QPcard to ask about their product referring to discussion on this site.
specifically I asked about capturing the right data for original artwork as compared to photos...

below is their second email...    I will be buying one of their charts as I find  passport colours too bright/gaudy in colours..  ( or is it me?)

Hi!

Lars already wrote a few things, but I though that some things were maybe still a bit unclear.

1) 203 is most probably better for you, since the 202 is slightly more sensitive to specular reflections. The 202 IS larger and easier to incorporate in larger works though, so as long as you have a reasonable control over lighting angles (and I guess you do, since you're into art-repro) 202 should not be a problem in your case.

2) The exposure has to meet those requirements:
-no colors overexposed in the raw file. When you open a file, no "blinkies" should be seen in the raw converter
-not severely underexposed. If you can add more than +2Ev exposure without getting blowing the "white" patch, you've probably lost some profiling accuracy.

There's a +/- 1Ev "window" of optimal exposure for the software to work with, and generally this is not very hard to satisfy. It WORKS with -3Ev exposure too, but the result is less accurate.

For your type of work (art-repro, of which I have done my fair bit...) often the exposure curve tends to mess things up a lot. The calibration gives you "accurate color" when everything is set to "zero", i.e no added contrast, no s-curve in the shadows and so on. When you add those things in, you oversaturate the midtones - where the exposure curve of a normal S-shaped type is at its' steepest.

steep curve - midtones - saturation increases
shallow curve - shadows and highlights - saturation decreases
When the RGB values has "one leg in the highlights and one leg in the midtones" you get a hue shift.

All of those things has to be adjusted for with human interaction, since there's no "perfect" exposure curve for any given type of art. But if you know the effect things have on your colors, they are quite easy to correct for. And when you have one good "oil, with semi-matte surface structure" setup, then this works for most pieces of similar qualities, regardless of artwork color constitution.

Feel free to as any more questions you might have, I will help you with setup of the calibration (via email of course...) :-) if you want some hints.

Greetings from Sweden
/Joakim Bengtsson
Senior developer, QPcard.com
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bill t.

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In regards to steep Curves increasing saturation, if you set the curve layer's blend mode to "Luminosity" rather than the default "Normal" you can add contrast without greatly affecting saturation.

Luminosity Curves all by themselves have a tendency to suck the life out of landscapes and such, but are well suited to art reproduction.  FWIW I have sometimes found it useful to have separate "Luminosity" and "Saturation" blend mode Curves layers both affecting the same image layer, with often very different curve shapes.
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kirkt

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FWIW, in addition to using the QP202 since the beta QPCalibration for making dcp profiles, I have also incorporated the QP202 into camera profiling using Raw Photo Processor's built-in camera profiling feature (uses ArgyllCMS).  The QP202 comes with descriptions of each patch in L*a*b, which you can enter directly into the text file (.cie) used by RPP's camera profiling module.  Attached is a screenshot demonstrating the camera profiling operation in RPP.  This flexibility permits both dcp profiles for ACR and icc profiles for everything else all from the same set of reference images - without having to use dcptool.  THe RPP camera profile module comes with the GMB CC24 built in as well.  If anyone is interested, I can shoot both the GMB CC24 and the QP202 and generate DCP and ICC and compare the results.  My CC24 is pretty old, but still seems to do okay.

kirk
« Last Edit: April 05, 2012, 10:41:49 am by kirkt »
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stefohl

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QP Card is working on an option to create a ICC-profile as well as .dcp-profiles. This is an add-on that will cost you €10. It says on their web page that it will be coming soon, but this is a small company, so expect that it will take some time before they get around to create this add-on.

I've tested some of the different software that will create a .dcp profile. The results are very different, but I prefer the more gentle, not so saturated look that QP Card creates. Passport profiles were too saturated for my taste, and also had a problem with blue colors turning purple.
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Stefan Ohlsson
Projektor [url=http://www
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