I have carefully read the instructions in Rawpedia about how to deal with images of colour charts for use with Dcamprof. However I’ve also read the instructions for my Spyder colorchekr24.
There it says I should adjust the white point (when inspecting the white patch) to 90% and the black to 4% (from the black patch) before exporting it.
Should I do this?
Nothing in the dcamprof documentation gives me a hint either way.
Hi !
Well, I’ve had to fiddle with this chart. Here’s a lengthy thread: how to create a dcp for an artificial light source
And a shorter one:
Is it possible to use "SpyderCheckr 24" in RT?
This requirement is valid for the Spydercheckr app.
What do you want to achieve?
I thought the spyderchecker was 96 for white and around 16 for the black patch… if you darken it lower I think that will alter the profile that is created away from the chart… my spyder is about 3 years old… I don’t recall those directions but I never used the software for it as it was only good for LR if I recall…
By the way, the ability to use HSL adjustments would be a nice addition to RT, don’t you think?
A. take picture of target,
B. do the magic with the manufacturer’s software → spits out an xml file with HSL adjustments,
C. copy those adjustments over to RT
A bit redundant, yes, but maybe more flexible than the current way of setting a DCP.
I haven’t checked what X-Rite or Calibrite software spits out, though, I don’t remember the various options, if there are multiple.
doesn’t RT have HSL under LAB settings?
Well, if you’re talking about that:
it’s quite different from what the .xmp file (built by the Spydercheckr software) for ACR contains:
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 4.2-c020 1.124078, Tue Sep 11 2007 23:21:40 ">
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdf:Description rdf:about=""
xmlns:crs="http://ns.adobe.com/camera-raw-settings/1.0/">
<crs:Version>6.1</crs:Version>
<crs:HueAdjustmentRed>-20</crs:HueAdjustmentRed>
<crs:HueAdjustmentOrange>-15</crs:HueAdjustmentOrange>
<crs:HueAdjustmentYellow>-20</crs:HueAdjustmentYellow>
<crs:HueAdjustmentGreen>-20</crs:HueAdjustmentGreen>
<crs:HueAdjustmentAqua>0</crs:HueAdjustmentAqua>
<crs:HueAdjustmentBlue>17</crs:HueAdjustmentBlue>
<crs:HueAdjustmentPurple>20</crs:HueAdjustmentPurple>
<crs:HueAdjustmentMagenta>-9</crs:HueAdjustmentMagenta>
<crs:SaturationAdjustmentRed>-12</crs:SaturationAdjustmentRed>
<crs:SaturationAdjustmentOrange>-10</crs:SaturationAdjustmentOrange>
<crs:SaturationAdjustmentYellow>-13</crs:SaturationAdjustmentYellow>
<crs:SaturationAdjustmentGreen>-20</crs:SaturationAdjustmentGreen>
<crs:SaturationAdjustmentAqua>-20</crs:SaturationAdjustmentAqua>
<crs:SaturationAdjustmentBlue>-10</crs:SaturationAdjustmentBlue>
<crs:SaturationAdjustmentPurple>-20</crs:SaturationAdjustmentPurple>
<crs:SaturationAdjustmentMagenta>17</crs:SaturationAdjustmentMagenta>
<crs:LuminanceAdjustmentRed>9</crs:LuminanceAdjustmentRed>
<crs:LuminanceAdjustmentOrange>5</crs:LuminanceAdjustmentOrange>
<crs:LuminanceAdjustmentYellow>16</crs:LuminanceAdjustmentYellow>
<crs:LuminanceAdjustmentGreen>5</crs:LuminanceAdjustmentGreen>
<crs:LuminanceAdjustmentAqua>12</crs:LuminanceAdjustmentAqua>
<crs:LuminanceAdjustmentBlue>3</crs:LuminanceAdjustmentBlue>
<crs:LuminanceAdjustmentPurple>12</crs:LuminanceAdjustmentPurple>
<crs:LuminanceAdjustmentMagenta>15</crs:LuminanceAdjustmentMagenta>
<crs:ParametricShadows>0</crs:ParametricShadows>
<crs:ParametricDarks>0</crs:ParametricDarks>
<crs:ParametricLights>0</crs:ParametricLights>
<crs:ParametricHighlights>0</crs:ParametricHighlights>
<crs:ParametricShadowSplit>25</crs:ParametricShadowSplit>
<crs:ParametricMidtoneSplit>50</crs:ParametricMidtoneSplit>
<crs:ParametricHighlightSplit>75</crs:ParametricHighlightSplit>
<crs:ConvertToGrayscale>False</crs:ConvertToGrayscale>
<crs:ToneCurveName>Medium Contrast</crs:ToneCurveName>
<crs:ToneCurve>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>32, 22</rdf:li>
<rdf:li>64, 56</rdf:li>
<rdf:li>128, 128</rdf:li>
<rdf:li>192, 196</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurve>
<crs:HasSettings>True</crs:HasSettings>
</rdf:Description>
</rdf:RDF>
</x:xmpmeta>
We’d have to know the scales and the positioning of the hues, to the very least.
You can partially do this…you will see it often in video color grading…they will open the vectorscope and crop the image to the main row of patches with red green blue etc and then you can tweak hues to line them up on the vectorscope…
I agree it would be a very neat addition. Now …is it something that enough people want badly enough for the already busy developers to start working on? Hopefully people will comment and request it and eventually someone place a feature request. As @priort mentioned, it is to some extent doable in LAB mode, but as you mentioned ACR is more detailed. Perhaps rather than a completely new item, it can be an additional (perhaps optional) rewrite of the LAB hue/saturation/luminosity tool, perhaps with a smoother transition between shades where extreme edits would cause artefacts
I notice the thread is ambling off topic as usual…
As I don’t have windows or mac, the makers software is not available to me.
I ended up experimenting - I already had a profile (using Dcamprof) without any adjustments for white or black point.
However I then did one just adjusting the white points and a further one adjusting the black points as well.
The one with both blacks and whites adjusted is the best - but I must look again at the values for the black patch : I don’t if it’s Micro 4/3’s have a low dynamic range, but getting the black point in the right range generated artifacts within the black patch. @priort may be right about the values.
I should get around to uploading some .jpegs of the results, but this forum has been down since I first posted and other things have been occupying me.
This is just an alternative (and inferior - poorly/minimally documented and with too few data points) way to do what the 2.5D HueSatMap tables do.
No. Stretching the exposure in oddball ways will completely screw up the resulting profile.
In general as long as the raw image itself is well exposed (white patch is close to clipping but far enough to have decent margin, helps to bracket with 1/3EV steps and choose the brightest non-clipping shot) exact levels should not matter. Adjusting the exposure slider in RT is only useful if you want the image to be easier to view in intermediary processing steps (Hugin for defishing, GIMP for pulling up the pixel coordinates of fiduciaries).
There’s currently a pull request that will improve the dcamprof workflow a bit, but it’s blocked due to rawpedia being in a sorry state for the documentation side of things, migrating rawpedia to something more maintainable has stalled for various reasons - An update on Rawpedia