Jump to content

how to icc profile a camera?


Recommended Posts

<p>What I tried till now resulted in profiles that had at best an peak DeltaE of 17-18 and an average of 7-8. Most of the times the profiles are to saturated and overly reddish... I use Argyll now, after worse results with basICColor Input.<br /> Here is the Capture One tethered studio procedure and what I tried:<br /> - evenly illuminated ColorCheckerc24 (double checked evenness)<br /> - tried different exposures with and for different applied curves<br /> - WB with BabelColor target</p>

<p>- applied "color view profile (former "Phase One - No color correction)" and either standard/linear<br /> - no curves / applied curves to match CC24 gray patches "ideal" values<br /> - everything else zeroed, including sharpening and NR<br /> - processed 16bit TIF with "Embed Camera Profile"</p>

<p>- in Argyll I use</p>

<ul>

<li><a href="http://www.argyllcms.com/doc/scanin.html">scanin</a> -v NameOfMyFile.tif ColorChecker.cht ColorChecker.txt</li>

</ul>

<p>and than</p>

<ul>

<li><a href="http://www.argyllcms.com/doc/colprof.html">colprof</a> <a href="http://www.argyllcms.com/doc/colprof.html#v">-v</a> <a href="http://www.argyllcms.com/doc/colprof.html#E">-D"Camera"</a> <a href="http://www.argyllcms.com/doc/colprof.html#q">-qm</a> <a href="http://www.argyllcms.com/doc/colprof.html#a">-am</a> <a href="http://www.argyllcms.com/doc/colprof.html#u">-u</a> <a href="http://www.argyllcms.com/doc/colprof.html#p1">NameOfMyFile</a></li>

</ul>

<p>in basICColor I also used the... basic settings ;-) keep camera gray and no absolute white</p>

<p>thanks in advance for any help with this</p>

<p>regards<br /> nino</p>

<p>P.S.: I basically want to see if I can get decent results with a custom ICC profile, before investing even in a ColorChecker SG. I couldn't get hold of a trial for the ProfilMaker or the MonacoProfiler, not even of the InCamera software.</p>

Link to comment
Share on other sites

<p>I think Xrite has a software called Passport or something. It just needs the std cheaper Colorchecker 24 patch (?) but it might support the more $$ ones too. The software's free.</p>

<p>Thou I think, for a digital camera profiling you need to do it in each setting, not much good for out and about photog but v good for controlled setting like weddings, where you might have one inside and one outside when light might not change a lot. So you can apply the profile thru out all the shots.</p>

<p>FWIW I have the Incamera Plugin, not sure if I have a older version, I used the 24 patch Colorchecker on my flatbed scanner - the results are horrible.</p>

Link to comment
Share on other sites

<p>If you are going to create an icc prcompliant profile for a specific camera body, what you reall yare doign is creatign a profile for not just that specific indivual body, but <em>also</em> the lens you used t o photogrpah the target , and the specific lighting condition (time of day and atmospheric condition if usign sunlight; light source(s) + Modifier(s) if using artificial light.</p>

<p>The profile will be inaccurate as soon as you change the lighting and the lens. </p>

<p>I have the SG ColorChecker Target and have profiled cameras with it in the past . I would rather not do this again. You might want to see if Thomas Fors script for ACR is available but I doubt it works on any version fo ACR past maybe ACR 2 or 3.<br>

A better approach is to use the Dng profiling software. there is the aforementioned ColorChecker Passport software from X-rite but you should also check out the more powerful and customizable Adobe DNG Profile Editor: http://labs.adobe.com/wiki/index.php/DNG_Profiles:Editor authored by Eric Chan. </p>

<p>With either of the DNG profile editors it is best to make a dual illuminant (daylight/flash & undimmed 3200˚K Quartz-Halogen) profile. </p>

Link to comment
Share on other sites

<p>Ellis,<br>

I have and use the CC passport (and before it was released I also used the script). I am aware of what it can and can not do.<br>

I need icc profiles for accurate color reproduction in a controlled studio lighting setup. I know that I will do this for every camera and every lens etc...<br>

If you have done this before, maybe you can help me or point me to documentation. Please do see my initial post on what I have already done and which software I used.</p>

Link to comment
Share on other sites

<p>For accurate color reproduction as in product and fine art shots, you're better off creating a DNG profile as Ellis pointed out.</p>

<p>But I wouldn't create a dual illuminant version for your purposes, just the 6500K table. From my experience with the dual illuminant profile, it generally adds a bit more blue to bright red as well as adding an overall red tinge to warm pastels depending on which way your default color temp leans toward green or red. It's very subtle.</p>

<p>From my experience getting exact color rendering of objects right next to my computer that I've shot in Raw, applying the custom DNG profile, editing by eye and saving the setting and applying to the rest in a studio shot series is MUCH quicker and less hassle over going the expensive software route. I think DXO Lab's site has an ICC profile creation package but it ain't cheap.</p>

<p>The DNG profile as I'm assuming whatever competing ICC software out there does is add small tweaks to shadow definition and correct for all primary color errors.</p>

<p>Whenever I apply my DNG profile to outdoor shots or shots I didn't create a profile for different lenses and lighting, I find I can fix quickly using ACR's HSL panel while getting the right look to the color temp.</p>

<p>Shooting in a light controlled studio should be a breeze getting accurate color reproduction.</p>

<p> </p>

Link to comment
Share on other sites

<p>Just to add another issue you're going to run into shooting a variety of objects or artwork is that each subject being shot in the studio may or may not bring their own oddball spectral reflectance characteristics not calculated for within in either DNG or ICC profile. For instance a dye based purple fabrics may show up blue while another synthetic purple fabric will look OK. You can always correct it using the HSL panel. It's a lot easier.</p>

<p>Don't know what you're shooting so your mileage may vary.</p>

Link to comment
Share on other sites

<p>Tim,<br /> Thank you for your comments.</p>

<p>I have to do some oil paintings and composite art work.</p>

<p>I tried the DNG rout with the DNG Profile editor. The latter is still a Beta product and does not work properly on my win7x64/16ram/ATI HD5770 studio workstation. Even if it would work, I see a few practical GUI problems (In the "color tables" tab, I can not work on a spot by the numbers, 'cause once the picker is not over the image anymore the numbers disappear. To find the same spot again is wishful thinking). Once those issues resolved, I am quite sure it'll be the way to go.<br /> For the moment x-rite sells two professional software packages for profiling. They are icc only and about USD 2.000.</p>

<blockquote>

<p>Shooting in a light controlled studio should be a breeze getting accurate color reproduction.</p>

</blockquote>

<p>I wish you where right! Here is a fine little introduction to the problem: http://www.betterlight.com/downloads/conference06_notes/color_Accuracy-ppt.pdf</p>

Link to comment
Share on other sites

<p>The ColorChecker DC will do a better job than the 24 patch target which wasn’t designed to build ICC camera profiles. But ICC camera profiles are fraught with frustrations. They are output referred, meaning they describe how a raw file has been rendered which is putting the cart in another city, not before the horse. If you have an Adobe product for raw conversion, you might try DNG profiles (Passport from X-Rite is free). </p>

Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

Link to comment
Share on other sites

<p>Thank you Andrew for keeping replying me. You continue telling me to change to Adobe. Well, as I tend to listen to those who should know better, I took an hour today to look into my DNG possibilities. Here in the studio that would be Lightroom/Bridge/Camera Raw/PS. I really dislike Lightroom for various reasons, but I could reduce it to thethered shooting only and than work with Bridge/Camera Raw/PS. I really like Bridge.<br>

Two things though:<br>

1) The DNG Profile Editor is still a beta and it is not stable here (win7x64). (BTW in the "Color Tables" Tab, when I want to edit colors by the numbers, once I move the cursor/picker away from the spot that I want to measure/modify the numbers change/disappear... So how to edit by the numbers? I don't want no visual adjustment.) So how would one build a top quality DNG profile?<br>

2) How come that a thing like Phase One-Mamyia-Leaf ignores DNG and that they continue to say that any real pro uses ICC? X-rite still sells for just under USD 2.000 their ICC legacy products ProfileMaker and Profiler saying</p>

<blockquote>

If you’re a professional fine art or commercial studio photographer with a discerning eye for color, the highest quality profiles are a must. When paired with an i1 measuring device, ProfileMaker™ 5 Platinum helps you connect each step in your color imaging workflow by creating and editing high quality, reliable ICC profiles. Achieve the most accurate digital color with highest confidence that it will remain consistent on each input, display and output device.

<p>(source <a href="http://www.xritephoto.com/ph_product_overview.aspx?ID=1211&catid=111" target="_blank">http://www.xritephoto.com/ph_product_overview.aspx?ID=1211&catid=111</a>)</p>

</blockquote>

<p>So that's not true anymore? They forgot to update their new website?</p>

Link to comment
Share on other sites

 

<blockquote>

<p>So that's not true anymore? They forgot to update their new website?</p>

</blockquote>

 

<p>That’s marketing speak. Its not necessarily more or less true today than back when it was written. In a very controlled situation like copy work setup, an ICC camera profile can indeed work very well because you are profiling a very specific and consistent behavior, much like profiling a scanner. If the illuminant changes, the dynamic range, the exposure and so forth, all bets are off. </p>

Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

Link to comment
Share on other sites

 

<blockquote>

<p>So we wait for the new x-rite software packages in order to be able to get good profiles?</p>

</blockquote>

 

 

<p>Not ICC camera profiles, it doesn’t make em. </p>

Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

Link to comment
Share on other sites

<p>and the DNG Profile editor? That's what might save the day, because as is, the DNG passport profiles are not... good. I today had to take an image of face mask painted in skin like tones with big pieces in dark orange and red on it. Although I build the profile from the beginning with the same attention for minute details, still the orange was way oversaturated and together with the red and the skin, off in terms hue. Noticeably so. Now I could tweak around, but tweaking here, untweaks there. To make things simple I also had real human skin on there.</p>
Link to comment
Share on other sites

<blockquote>

<p>Although I build the profile from the beginning with the same attention for minute details, still the orange was way oversaturated and together with the red and the skin, off in terms hue. Noticeably so. Now I could tweak around, but tweaking here, untweaks there. To make things simple I also had real human skin on there.</p>

</blockquote>

<p>What's your light source? And can you post this image showing before and after profile application.</p>

<p>What you just indicated sounds very similar to my experience shooting a wide range of objects including real skin tone under two 5500K 100watt Ottlight CFL's using a custom DNG profile for those lights. The profile doesn't fix all colors for every different object I shoot under these lights. It requires tweaks to specific colors mainly reds and oranges.</p>

<p>What I find is the appearance of contrast perceived by our eyes viewing actual objects lit under various lights will not exactly match the DNG profile's which have color tables established by a fixed exposure induced contrast ratio. Its contrast is based on referencing a flat target whose numbers are defined by measuring with a spectro at the factory and calculated within a linear space. It gets you in the ballpark establishing individual colors without noticeably changing contrast and luminance.</p>

<p>Different objects will give off there own specific color characteristic according to the light source and contrast ratio. It's the same problem I had profiling a scanner using an IT8 silver halide target. Once I built the ICC profile and applied it to some artwork or fabric design I scanned, the profile made the scan of those natural objects look like crap while all silver halide prints matched exactly.</p>

<p>The digital camera is a lot more forgiving capturing natural objects (not silver halide prints) because it's not strapped to using a scanner's bluish fluorescent light source combined with the limited and/or specific spectral reflectance characteristics of a silver halide IT8 target. You're shooting a sculpture who's pigments reflect back under a fixed light source a specific luminance, hue and saturation level not calculated for in the X-rite's target.</p>

<p>I can usually fix those kind of color errors you describe by reducing/changing contrast induced tonal distribution and tweaking HSL and color temp. If you're going to shoot a wide range of different objects made from material not included in the X-rite color chart, you're going to have to do some tweaking.</p>

<p>Just a tip but I'ld suggest not making the image look dramatic with beefed up contrast. As an example ever notice when you increase contrast on an image in Photoshop or ACR/LR, you get luminance, hue and saturation shifts? Sometimes applying contrast with a wide sloping curve tweak can fix these kind of contrast induced color errors instead of just using the contrast slider.</p>

Link to comment
Share on other sites

<p>Ellis,<br /> my major concern is the 5D2's reds (orange, pink...), but for copy work I also need the HDH40 to be spot on. For big things I rent PhaseOne, or Leaf as a matter of fact.</p>

<p>Tim,<br /> for my studio work, I use natural day light (which is abundant and extremely predictable where I am) and my Profoto D4 with Profoto and Elinchrome light-shapers.<br /> What you describe sounds all too familiar, especially contrast tweaks giving HLS shifts. I only disagree with</p>

<blockquote>

<p>I can usually fix those kind of color errors you describe by reducing/changing contrast induced tonal distribution and tweaking HSL and color temp. If you're going to shoot a wide range of different objects made from material not included in the X-rite color chart, you're going to have to do some tweaking.</p>

</blockquote>

<p>I think, one can tweak very well to obtain PLEASING results. Only, I very often need more ACCURATE rendition. How do you get accurate with the DNG Profile Editor? How to edit by the numbers?<br /> An example, maybe you can help me:<br /> In this example (not real, just a quick screen shot), I photographed a ColorChecker, picked on a few colors. Now I can tweak them, but ONLY VISUALLY. There are no numbers showing anymore. In the Advanced Color Editor of Phase One's Capture One RAW converter, there are the tools for that, there are "color read out" points which you can set on the picture. They change as you tweak. Why can't there be such a thing here?</p>

<p> </p><div>00Xth1-313681584.jpg.107be588fbbdbb5acac8ad04f1f97694.jpg</div>

Link to comment
Share on other sites

<p>BTW you could than use the ICC profile in Capture One and still tweak and edit the profile (if need would be). But th in C1, as mentioned you have the ability to set "color read out" point, so you actually see what you are doing.</p>

 

<blockquote>

<p>So here is a video that explains the, to me, more convincing and practical approach, which is ICC profiling:<br /> <a rel="nofollow" href="http://www.luminous-landscape.com/reviews/accessories/coloreyes-commercial.shtml" target="_blank">http://www.luminous-landscape.com/reviews/accessories/coloreyes-commercial.shtml</a></p>

</blockquote>

<p>P.S.: Don't miss that video!</p>

Link to comment
Share on other sites

<p>None of this work, profiling with DNG profiles or otherwise is “<em>accurate</em>” (meaning colorimetrically correct values). Its all about output referred, pleasing (expected, desired) color. see:<br>

http://www.color.org/ICC_white_paper_20_Digital_photography_color_management_basics.pdf</p>

Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

Link to comment
Share on other sites

<p>It's understood that this paper from 2005 and it's arguments you mention, where known to the participants at Sheridan college in 2007 in this very informative video on that page. Michael Reichmann insists in this video about this color eyes icc camera profiling technique that it convinces him.<br /> Also, "accurate" is meant in terms of final output, i.e. a critical client compares the repro to the original and agrees that it just looks like the original.</p>

<blockquote>

<p>So here is a video that explains the, to me, more convincing and practical approach, which is ICC profiling:<br /> <a rel="nofollow" href="http://www.luminous-landscape.com/reviews/accessories/coloreyes-commercial.shtml" target="_blank">http://www.luminous-landscape.com/reviews/accessories/coloreyes-commercial.shtml</a></p>

</blockquote>

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...