Color Space Conversion but out of gamut color shift

<p>Dear All,<br>

I am editing in ProPhoto colorspace and when preparing file to print in Fuji Frontier 570, I try to convert the color space from ProPhoto to sRGB. However, even I am using "Perceptual" in the conversion, the color still shift a lot. How can I remediate this?</p>

 

<p>you might want to try some selective desaturation and/or exposure change to pull those colors back into sRGB gamut.</p>

test

<p>Try converting to Adobe RGB instead of sRGB, and use "Relative Colorimetric" instead of "Perceptual" for rendering intent. If you're using your editor's color management, turn your printer's colormanagement routines.</p>

<p>Disregard the "test" post...</p>

<p>There should not be a color shift with a well built profile, in fact, converting from Adobe RGB (1998) or even sRGB to the output profile should produce very, very similar color appearance (you may want to try this). Are you seeing blues shifting magenta? As William said, try RelCol too (even Saturation). Where did this profile come from?</p>

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<p>I try to convert the color space from ProPhoto to <strong>sRGB</strong>...</p>

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<blockquote>even I am using <strong>"Perceptual"</strong> in the conversion, the color still shift a lot.</blockquote>

<p>There's no "perceptual" table in the matrix based sRGB color space unless you're converting using a table based Fuji Frontier custom profile which you have not indicated. </p>

<p>You've missed something in describing what you are doing. </p>

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<p>There's no "perceptual" table in the matrix based sRGB color space unless you're converting using a table based Fuji Frontier custom profile which you have not indicated.</p>

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<p>That’s exactly how you get a Perceptual rendering (from the output profile, not the source profile).All output (printer) profiles should have all 3 tables. By the time the output profile comes into the scene, its getting Lab from the PCS (from sRGB). If you conduct a matrix to matrix profile conversion, again, the secondary profile is being fed Lab, but it only has a colorimetric table, in which case what you wrote above would be true.</p>

<p>The question now is, what kinds of shifting are being seen going from ProPhoto (or sRGB) to the Fuji output color space and why the Fuji is causing this shifting. </p>

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<p> I try to convert the color space from ProPhoto to sRGB</p>

</blockquote>

<p>The OP is converting from ProPhoto to sRGB, not to a Fuji Output color space. As Tim pointed out, there is no perceptual conversion to a matrix color space, at least in Version 2 ICC profiles.</p>

<p>However, I agree that you should not see color shifts. What should happen is that some colors get saturated or blow out, due to the smaller sRGB color space (unless this effect in the saturated colors is perceived as a color shift)</p>

<p>Besides reducing saturation or, even better, reduce vibrance before converting to sRGB, another option is to use a version 4 sRGB, which do allow for perceptual conversion. You can find the profile <a href="http://www.color.org/srgbprofiles.xalter">here</a> </p>

<p>The way I read the OP’s question is he’s getting a shift form ProPhoto to Fuji. There’s no way a ProPhoto to sRGB conversion would produce a true color shift (I’ve never, ever seen this). </p>

<p>A neutral or gray tone will not shift when converting from Prophoto to sRGB, but if you have a wide gamut monitor and an image in Prophoto with a large area with colors outside the gamut of sRGB, you may perceive a color shift when converting to sRGB, since that large area will have a less saturated color (it would be the most saturated available in the new color space)</p>

<p>Well I just opened a Granger Rainbow built in Lab, converted to ProPhoto, then sRGB. I see no color shifts (viewing on a wide gamut, NEC 3090). There is of course a difference in perceived saturation and smoothens but nothing I see I would describe as a color shift, even in those notoriously difficult blues. </p>

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<p>The way I read the OP’s question is he’s getting a shift form ProPhoto to Fuji. There’s no way a ProPhoto to sRGB conversion would produce a true color shift (I’ve never, ever seen this).</p>

 

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<p>You're probably reading too fast. Maybe too much coffee? </p>

<p>I read something totally different. That's why I emphasized with the OP's own quotes and you still didn't catch that. I was going to make the same assumption as you that he's getting color shifts converting to the Fuji profile and NOT SRGB, which makes more sense, but I thought it would be better to have the OP clarify just so we're all on the same page.</p>

<p>Again, there should be no such shifts from ProPhoto to sRGB. Now maybe this is a display issue, I don’t know but it seems far more likely to see a shift going from either working space to the output color space. We need the OP to clear this up for us and if it is ProPhoto to sRGB, I’d sure like a look at a low rez image to attempt this on my end cause its not something I’ve yet seen. </p>

<p>Andrew, is it possible for someone to select a printer profile as their display profile? Just curious.</p>

<p>I say this from my one consulting gig I had several years ago where their display of the PDI target was so screwed up there was no way a canned display profile was the cause. It was on a Windows XP system. It looked like a table based profile was loaded.</p>

<p>He had an odd name for his display that was worded similarly to the name of the paper profile made by the $3000 ProfileMaker package a local university art professor happen to come by and build for him in the past.</p>

<p>Later after I recalibrated with his SpyderPro 2 package, he mentioned he'ld been fiddling around changing display profiles and that's when things went wrong.</p>

<p>I've never heard of it being possible to load into the video LUT a printer profile. Just wondered if that is possible on some systems. I know you can't do that on the Mac.</p>

<p>sRGB is NOT the color space of the Fuji Frontier 570, regardless of what you've been told or led to believe. The color space is very specific to the print paper. Therefore, you should have a profile for the machine and paper type. Fortunately, I think you can find many of these at Drycreek and many of them are satisfactory even though they were not made from the machine in your neighborhood. You will learn you're going from one of the largest color gamuts to one of the smallest color gamuts. However, a PERCEPTUAL rendering should result in just that; PERCEPTUAL.</p>

<p>There are relatively few color colors found in nature that may be lost in the Frontier print process. A classic example is a very bright synthetic sweater worn by a high school senior for her portrait. (A manmade fabric / dye combination, not found in nature.) Another classic example is a stack of brightly colored towels on sale at JC Penny. (Again, a manmade fabric / dye combination, not found in nature.) "Natural" scenes usually reproduce well from the Frontier.</p>

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<p>Andrew, is it possible for someone to select a printer profile as their display profile? Just curious.</p>

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<p>That’s certainly possible. </p>

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<p>Andrew, is it possible for someone to select a printer profile as their display profile? Just curious.</p>

</blockquote>

<p>It depends on CMM.<br>

In ICC profiles there is a "device class signature".<br>

"output class signature" is for printer profiles.</p>

<p>Hi <a href="../photodb/user?user_id=361342">Andrew</a>,<br>

Yes. It is a shift in saturation (actually is the blue) in the conversion from the ProPhoto to sRGB.<br>

The fuji lab cannot provide paper specific profile, so I am using an sRGB for preparing file to send to the lab.<br>

Besides, sRGB, what profile can I use?</p>

<blockquote>

Yes. It is a shift in saturation (actually is the blue) in the conversion from the ProPhoto to sRGB.<br />The fuji lab cannot provide paper specific profile, so I am using an sRGB for preparing file to send to the lab.<br />Besides, sRGB, what profile can I use?

</blockquote>

<p>First, what you report doesn’t sound Kosher. You have the display calibrated, have proper profiles in use? Can you supply a small rez file we can convert from ProPhoto to sRGB? You may want to circle with a lasso and stroke the area where you see this shift. </p>

<p>Second, you’d ideally be getting an output profile from the lab to do the conversions. </p>

<p>Just a heads up and not sure if you all have already heard about this, but Fuji Frontiers are putting out what they call a dry process printer in some Walmarts. I just came back today from my local Walmart to check out their new photo lab after they renovated the whole store and they got rid of their lazer exposed silver halide printer. The head clerk at the counter said the new Fuji Frontier now prints inkjet. It's a much smaller printer by comparison.</p>

<p>Saw some customer's sample snap shots and found there's a big improvement in skin tone rendering much like you see on Epson inkjets where there's a nice caramel hue in Caucasian skin tone instead of there typical (at this location) pinky peach handing them sRGB.</p>

<p>Hi <a href="../photodb/user?user_id=361342">Andrew</a>,<br>

The monitor is calibrated with Spyder2. The file is loaded from RAW in ProPhoto and edited.</p>

 

<p>What do you see when you go back to the raw converter and select sRGB instead of ProPhoto? </p>

<p>Dear All,<br>

The sample file is in <a href="http://www.filesonic.com/file/48716971/UpLoadColorSpace.tif">http://www.filesonic.com/file/48716971/UpLoadColorSpace.tif</a></p>

<p>The link goes to a page saying the file was deleted. </p>

<p>Hi Andrew,<br>

The file is attached in the post thread itself. File name as UpLoadColorSpace.tif<br>

Thanks.</p>