"Un-Photographable" Colours?

<p>Okay, this is going to sound queer. But here's a phenomenon I came across several times now, and I do not know how to explain it - perhaps one of you can help?<br>

I do product photography for an online clothes store, and generally the work is easy enough. However, some colours - mainly red-tinted purple, but also some fluorescent yellow and vibrant pink - just <em>won't be photographed</em> the way they look to the eye. The purple just looks a lot more blue than ruby, and the yellow and pink look deep and saturated and loose their fluorescence. <br /> No matter how I fiddle with the white-balance (custom) or exposure or what way I turn the polarizing filter I shoot with, those colours never look the same in real and on the photograph. It isn't just a slight difference, either, but they look two completely different colours.<br>

It's not a problem to adjust the colours in Lightroom later to fit the original. But <strong>I would like to know how the discrepance ever comes to be, what could be the cause and how to eliminate it.</strong> It would safe me some time post-processing, and also, that's one of the most fascinating phenomena in photography I've come across to date. It's a complete mystery to me.<br>

I found some information on <a href="../photo/edscott/spectsel.htm#01">Spectral Selectivity</a> here on photo.net, and I thought it might have to do with the way certain colours are processed in the eye that the camera cannot imitate. But surely someone would have thought of a work around by now?<br>

Equipment used:<br /> Nikon D200 with kit lense <br /> Polarizing filter <br /> White carton backdrop<br /> 2x 300W flash with umbrella (for the main subject) <br /> 2x 600W flash with umbrella (for the background and sometimes backlight)<br>

I'd be thankful for any information or educated guesses.</p>

<p>.</p>

<p>Yes, there is <strong><em>violet reproduction therapy for digital sensor capture</em> </strong> to address the paucity of accurate violet. Let's all search for it, but I don't remember a product name or if it was vapor ware or real. I believe it was a plug-in, but I can't remember if it addressed Raw or any image.</p>

<p>Note, I also have an inability to see violet flowers, for instance, that come out blue. If we can find this <em><strong>violet recovery tool</strong> </em> . I may use it, too.</p>

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<p>.</p>

<p>Is THIS it? From <a href="http://www.steves-digicams.com/digsoftware_color.html">http://www.steves-digicams.com/digsoftware_color.html</a></p>

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<p><strong>DCF Full Spectrum Color</strong> <a href="http://www.tribecalabs.com/products.htm" target="_blank">http://www.tribecalabs.com/products.htm</a> <br /> DCF Full Spectrum is compatible with Photoshop 7 and higher, PC and Mac. A revolutionary digital color model that expands the spectral capabilities of your digital camera for unsurpassed color accuracy. This unique technology allows your camera to reproduce all colors accurately, including difficult hues such as <strong><em>violet, deep blue and sunlit green</em> </strong> .</p>

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<p>See also:</p>

<blockquote>

<p><strong>Full Spectrum RGB </strong> <a href="http://www.fullspectrumrgb.com/">http://www.fullspectrumrgb.com/</a> $49 and free trial version<a href="http://www.fullspectrumrgb.com/"><br /> </a><br>

Instantly improve the color<br /> accuracy of your digital images<br /> with Full Spectrum RGB<br /> - Rich natural colors quickly and easily<br /> - Save hours in workflow<br /> - Choose from three preset color transformations<br /> - Customize your own unique color formulas and lighting effects<br /> - Save your personalized color settings<br /> Full Spectrum RGB is a revolutionary digital color model that expands the spectral capabilities of your digital camera. This unique technology allows you to instantly reproduce all the colors of the visual spectrum in your digital images.</p>

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<p>Let us know if this helps.</p>

<p>----------</p>

<p>Secondly, calibrate your DSLR system including lights, filters, and lens AS A SYSTEM:</p>

<blockquote>

<p><strong>QPcard RAW package</strong> <a href="http://www.qpcard.se/BizPart.aspx?tabId=31&catId=1&prod=4&tci=145">http://www.qpcard.se/BizPart.aspx?tabId=31&catId=1&prod=4&tci=145</a><br>

Calibrate your digital camera for RAW shooting using QPcard 201, Adobe Photoshop and Adobe Camera RAW (ACR).<br /> <br /> In ACR there is a tab called "Calibrate". Here you will find sliders for adjustment of Shadow Tint, Red, Green and Blue Hue and Saturation. Using these sliders you can finetune the color reproduction of Adobe Camera RAW converter. However, it is almost impossible to succeed without a reference color target like the QPcard 201.<br /> <br /> Fine tuning of RAW can be achieved manually or automatically. The manual procedure is described by Bruce Fraser here <a href="http://www.creativepro.com/story/feature/21351-1.html">http://www.creativepro.com/story/feature/21351-1.html</a> <br /> <br /> In order to accomplish this with QPcard 201 you need a reference image with RGB values. This image can be downloaded here.<br /> <br /> But there is also an automatic way to go. Rags Gardner at <a href="http://www.rags-int-inc.com">http://www.rags-int-inc.com</a> has a Technology department on his site: <a href="http://www.rags-int-inc.com/PhotoTechStuff/">http://www.rags-int-inc.com/PhotoTechStuff/</a> with lots of useful information and solutions for digital photographers. Rags has written a Javascript for automatic color calibration with ACR. The script can be downloaded free from Rags site here:<br /> <a href="http://www.rags-int-inc.com/PhotoTechStuff/ColorCalibration/">http://www.rags-int-inc.com/PhotoTechStuff/ColorCalibration/</a> <br /> <br /> You can read Rags explanation here:<br /> <a href="http://www.rags-int-inc.com/PhotoTechStuff/AcrCalibration/">http://www.rags-int-inc.com/PhotoTechStuff/AcrCalibration/</a> <br /> <br /> It is possible to carry out the ACR calibration with only a QPcard 201. However, mounting the color card on the bigger QPcard102 gives several advantages. You have the perfect target for custom white balance setting and 18% exposure setting. You also have a perfectly neutral background when you take the calibration picture of QPcard 201. The importance of a neutral background is emphasized by Rags Gardner.<br /> <br /> The QPcard RAW Package consists of one QPcard 201 and one QPcard 102.<br /> Price in EUR: 43.71 Price: $56.67</p>

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<p>Yes, no, maybe? Are we getting anywhere? Do I have to mention <a href="http://www.ExpoDisc.com/">http://www.ExpoDisc.com/</a> ?<br>

.</p>

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<p>I thought it might have to do with the way certain colours are processed in the eye that the camera cannot imitate. </p>

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<p>Although you can get great colour reproduction for a limited range of colours, ultimately there will always be a point at which you're stuffed. You need a little understanding of how the colours your eye sees are approximated by the R-G-B sensor array in the camera, and the R-G-B phosphors or LCD pixels in your screen. But they're only approximations to the eye's response (which itself varies from individual to individual) and there are always going to be out-of-gamut colours that you can see (for instance created by different chemical dyestuffs), but simply cannot be reproduced on an RGB screen (or even worse, in CMYK printing).</p>

<p>On a side note, the reason that people seem to find this hard to accept is that we learn about colour, photography, printing, dyes, and all allied topics by reading about them in print or on screen. Since it's impossible to show a colour in these media (by definition) that can't be captured or reproduced easily, it comes as something of a shock to see one in real life!</p>

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<p>Hi Olivia. I've worked with color quite a bit, and know there are many potential pitfalls. I think that, in principle, any color that can be seen (normal human eye, etc.) ought to be able to be recorded (not necessarily displayed or printed), by a digital camera. That said, I don't know how good a job the D200 does at this.</p>

<p>If it were me, I'd start out being suspicious of both the camera's inherent response and the lighting. You indicated you are using some flash units, I wonder if the flash tubes are "UV coated", inexpensive units might not be so. If not, you may be seeing fluorescing of the fabric. How to check for this: I'd try a 2B filter over the flash, do a custom white balance and reshoot, checking for a difference. If no 2B filter available, perhaps try a test shot in direct sunlight (with custom WB); if the sunlight shot looks correct, then UV from the flash was a likely culprit. Note: the possible UV issue aside, the electronic flash should do a good job.</p>

<p>There's a handful of other things to consider, but this is an obvious starting point. Also, I don't know how you actually evaluate the color, but if shooting under electronic flash, this approximates sunlight, so you ought to look at the fabric in sunlight to see if it's similar. Looking at the fabric under fluorescent lighting can be a can of worms.</p>

<p>Can you possibly post an image showing a sample of some of the colors, as shot, along with your corrective adjustments?</p>

<p>Olivia, Years ago, one of my very lucrative accounts was a high end mens fashion chain. This has always been a problem, and I used to have to shoot images of the clothing before taking it out for the model shots because ties and other clothing simply do not photograph with the same color sensitivity with what you see. Those were the film days when we didn't have PhotoShop to correct the colors and had to know about problems before the final shoot.</p>

<p>It comes about simply by sensors and film not seeing the same spectral sensitivity as your eye.</p>