Vuescan colour spaces

[csaba_brindza]

<p>Hi Guys,<br>

I'd be grateful to hear your advices for my problem. <br>

I'm scanning with Vuescan on Epson V700, using a calibrated Eizo monitor on OSX. For postprocessing I'm using Aperture software. <br>

I'm setting the colours during scanning in the Vuescan software, but here comes my problem. I'm quite confused about the output colour space / monitor colour space combo at the Color tab in Vuescan. My 2 main problems:<br>

1. If i use Adobe RGB for the Output colour space then i get muddy colours and unable to get the right colours in Aperture after scanning. If i use SRGB or Apple RGB for the output colour space then my colours are superb. But this way I'm afraid of losing some details due to the lower gammut. <br>

2. For the monitor colour space I'm using my icc profile generated from calibration. But after scanning, if i import the tiff files to Aperture I'm getting different, darker images. If i choose Apple RGB for the monitor colour space then I get the same images after importing to Aperture. I'm totally confused here and would like to hear your toughts.</p>

<p>Thanks,</p>

<p>Csaba</p>

<p> </p>

[peter_gilbert4]

<p>When scanning color negatives, I set Color balance:none, Negative Vendor:generic, Brightness:1 and RGB:1. I scan RAW 6400 spi 48-bit RGB with compression at 3. I have profiled my V700 and of course use that (scanner.icc on my Mac). I use ProPhoto RGB as my output color space and Monitor ICC profile, but since my output is a life-sized scan (i.e. 6x6cm) that looks exactly like the negative (i.e. orange mask) I'm not sure the output color space has any real effect.<br>

<br /> When I open the scan in Photoshop the very first thing I do is Edit>Assign Profile>Epson V700-film then run the scan through ColorPerfect. After that, I convert the profile Edit>Convert to Profile>ProPhotoRGB (working profile).</p>

<p>For B&W negatives I also scan as 48-bit RGB with same settings in Color Tab, and output color space. In Photoshop, after running through ColorPerfect (as a color negative) I set Edit>Convert to Profile>Gray Gamma 2 (working profile)</p>

<p>Not sure if this is all technically "correct" but it seems to work for me :-)</p>

[digitaldog]

<p>The processing color space in Aperture is Adobe RGB (1998) so the first concern I have is that you are getting a mismatch between the scanning software and Aperture in terms of color appearance. That should not be happening. Do you have any other ICC aware applications you can check the image with to see what produces a match (Even Preview should recognize an embedded profile). It sounds like the scan isn't getting Adobe RGB embedded or it's not really Adobe RGB (1998)? </p>

[csaba_brindza]

<p>Thanks for the replies guys.<br /> I've made some testing, compared the scanned results in Aperture, PS and Preview. The final scans were just the same in all of the three softwares. When the monitor colour space was my ICC profile then the tiffs were much darker in the 3 softwares compared to Vuescan. But the colours remained the same. It was the case if i used Adobe RGB or SRGB for the output colour space.<br /> However, when i used Apple RGB for the monitor colour space then i get exactly the same images everywhere. Now i don't have any clue what's going on:) Is it a brightness issue somewhere or what do you think?<br /> I know that i should fundamentally use my ICC for the monitor colour space. Furthermore i should use Adobe RGB for the output colour space, but i just get superb scan results with SRGB. The skin tones are much better compared to Adobe RGB.</p>

[digitaldog]

<p>The display color space should never be selected in any application, it is only used for preview purposes and all ICC aware applications will 'find' and use that profile. The display profile is divorced from the editing of your images, hence RGB working spaces like sRGB, Adobe RGB etc. </p>

[csaba_brindza]

<p>Yes, it's clear, but anyhow there is this option in Vuescan where i have to choose something for the monitor colour space. And choosing results very different colours, that's my problem</p>

[csaba_brindza]

<p>Yes, it's clear, but anyhow there is this option in Vuescan where i have to choose something for the monitor colour space. And choosing results very different colours, that's my problem</p>

[csaba_brindza]

<p>Yes, it's clear, but anyhow there is this option in Vuescan where i have to choose something for the monitor colour space. And choosing results very different colours, that's my problem</p>

[digitaldog]

<blockquote>

<p>but anyhow there is this option in Vuescan where i have to choose something for the monitor colour space.</p>

</blockquote>

<p>I don't use it. But there isn't a need to select this so like Photoshop and others, I suspect that's not an option. ICC aware applications are smart enough to '<em>find</em>' the system profile for the display so you shouldn't have to set this up. It sounds more like whatever is being 'embedded' into the scan isn't being properly recognized but that's just a guess. Bottom line is, the scanning software should produce a preview that looks identical to the image after it is opened in an ICC aware application like Photoshop.</p>

[peter_gilbert4]

<p>Vuescan expects you to insert "ICC Profile" for Monitor Color Space (the default is sRGB but you need to change that), and then in the following box for Monitor ICC Profile you need to provide the exact location of the latest profile you have created for your monitor, e.g. on my Mac: Users/.../Library/Colorsync/Profiles/...</p>

[steveg]

<blockquote>

<p>Vuescan expects you to insert "ICC Profile" for Monitor Color Space (the default is sRGB but you need to change that), and then in the following box for Monitor ICC Profile you need to provide the exact location of the latest profile you have created for your monitor, e.g. on my Mac: Users/.../Library/Colorsync/Profiles/...</p>

</blockquote>

<p>For windows users the profile is in: windows/system32/spool/drivers/color/...</p>

 

[Uhooru]

<p>As in Peter's above (for Mac). Andrew Vu Scan seems to make you select something for Monitor color space and then has another selection for output color space. Its the output where I set it for Adobe RGB. I believe that that assigns Adobe RGB to the file. But when I changed my "monitor color" space to my calibrated ICC profile as explained by Peter, it really changed the appearance on the monitor in VuScan from the default selection which I believe was like sRGB. <br>

Do you think that in a way that Vu Scan is sort of acting like a "non ICC aware" device in that it instead of just being aware of the prifile, instead forces you to choose a profile? Emperically, when I view the files after the ICC monitor box is chosen through the process of bringing them into P.S. and then output for web, the visual appearance is the same from vu-scan >PS>web. When I have the monitor space in lets say sRGB or Adobe RGB it looks very different from the Tif that is out put from Vu Scan and then viewed in preview or P.S. etc. It seems to work well using the ICC profile for monitor space.</p>

[digitaldog]

<blockquote>

<p>Andrew Vu Scan seems to make you select something for Monitor color space...</p>

</blockquote>

<p>Unnecessary and unduly complicated but whatever. Photoshop doesn't, LR doesn't (none of the Adobe suite), Preview on Mac (all other ICC aware Mac apps). </p>

<blockquote>

<p>Its the output where I set it for Adobe RGB. I believe that that assigns Adobe RGB to the file.<br /></p>

</blockquote>

<p>If the data is in Adobe RGB it should. It should embed (tag) any color space you select that defines the scanned data or you've got RGB mystery meat. </p>

<blockquote>

<p>But when I changed my "monitor color" space to my calibrated ICC profile as explained by Peter, it really changed the appearance on the monitor in VuScan from the default selection which I believe was like sRGB.</p>

</blockquote>

<p>That makes sense (that the color appearance would change). Is it correct? </p>

<blockquote>

<p>When I have the monitor space in lets say sRGB or Adobe RGB it looks very different from the Tif that is out put from Vu Scan and then viewed in preview or P.S.<br /></p>

</blockquote>

<p>When you say <em>Monitor Space</em>, I assume that means the color space defined by whatever ICC profile you have of your display. The profile that this product should just go out and find by itself. If this indeed is the monitor color space, you'd <strong>never</strong> select anything like sRGB or Adobe RGB (1998) that's not the display color space. You should always be selecting the actual display profile (on Mac, in System Preferences>Display>Color, you'll see the profile the system is using. Also in Photoshop, if you select the Color Settings, RGB working space and look at the popup menu items, you'll see "Monitor:XXX" where XXX is the name of the display system profile. You never select this, it is just Photoshop showing us the display profile it's using). <br>

In terms of how ICC color management and profiles are supposed to work, here's a white paper from Adobe which should be how other applications handle display and RGB working spaces. </p>

<p>http://www.adobe.com/digitalimag/pdfs/phscs2ip_colspace.pdf</p>

[Uhooru]

<blockquote>

<p>If this indeed is the monitor color space, you'd <strong>never</strong> select anything like sRGB or Adobe RGB (1998) that's not the display color space. You should always be selecting the actual display profile (on Mac, in System Preferences>Display>Color, you'll see the profile the system is using.</p>

</blockquote>

<p>Yes, that's what I thought and had been doing...thanks. "Monitor Space" is Vu Scan's term and it seems to be just what you are saying. Also, thanks for the link.<br>

</p>