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A colour space is a specific organization of colours. In combination with physical device profiling, it allows for reproducible representations of colour, in both analogue and digital representations. The colour spaces most commonly encountered in photography are Adobe RGB and sRGB.

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Color schemes and perception: If L*-linearity does not imply perceptual intensity linearity, then what is the best metric of perceptual intensity? [on hold]

This question was in part motivated by this MathematicaSE question and Matteo Niccoli's geophysics blog post on color schemes. The underlying concept of Niccoli's perceptually-balanced color schemes ...
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1answer
75 views

Why does L*=0 not correspond to black in the L*a*b* color space?

According to two sources I found, in the CIELAB LAB colorspace a value of L*=0 corresponds to black. Quoting Wikipedia: The three coordinates of CIELAB represent the lightness of the color (L* = 0 ...
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3answers
116 views

What is the advantage of using L*a*b in Photoshop?

In a couple posts, I noticed throw-away remarks about using Lab as the recommended or only serious thing to do. Why?
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2answers
44 views

Why can I see beyond sRGB in CIE Chromatic Diagram

According to CIE 1931 color space chart, the sRGB gamut is what's inside the triangle: As you can see from the diagram, blue is shown outside the sRGB gamut (at about 460 nm wavelength). Knowing ...
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2answers
81 views

Color spaces for large prints / and or web

I am using a MacBook Pro (2011) and edited a photo from camera raw into photoshop. The color space is set to sRGB within photoshop. I used Lightroom to export to JPEG while ensuring that the color ...
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1answer
50 views

Weighted conversion to a fixed palette

for some reason I need to convert a picture to a 16-color palette. While the conversion itself is nothing special, I need the final result to stick to a well-defined color proportion. This means, for ...
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7answers
683 views

Is CMYK less blue than sRGB?

When comparing the sRGB and CMYK color spaces, the sRGB color space encompasses much more blue than the CMYK does. Open Photoshop using sRGB as the color space. Fill the entire image with blue ...
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0answers
31 views

For photos that end up on the web, does Adobe RGB matter? [duplicate]

To pay the bills I am a developer first, web stuff mainly. All of my photography, so far, has just ended up on the web, and I don't think that that will change anytime soon. I shoot in RAW and then ...
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3answers
118 views

does anyone see technical meaning in going from RAW to an 8 bit TIFF?

I was watching a video about frequency separation techniques for skin retouching in Photoshop. The subject is irrelevant, but I mention it because this comes from a decent source and a high-end ...
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1answer
191 views

What colour space does Adobe Lightroom use in the Develop Module?

What colour space does Lightroom use when you load an Adobe RGB or SRGB tiff/jpeg file into the Develop module? The reason I ask is because I was told that the develop module always uses the ProPhoto ...
2
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1answer
76 views

RGB working color space that uses the L* tone response curve?

There are a couple of RGB color spaces out there - LStar-RGB.icc and ProStarRGB.icc- that use the L* tone response curve. What's the supposed advantage of using the L* TRC over using a gamma curve as ...
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2answers
216 views

Is it possible to convert to and from LAB color space without loss of quality?

Can I safely convert from sRGB or Adobe RGB to L*a*b color space and back without quality loss? Lab is the widest color space and therefore it should be possible to convert colors into this color ...
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0answers
97 views

Postprocessing ColorSpace: Windows System with two graphics cards (Quadro and GTX) one AdobeRGB the other sRGB color space

I couldn't find any satisfying answer to this question. I plan to build a postprocessing PC which has a Quadro K4000 and a GTX680 graphic card installed. I plan to buy two monitors which are: NEC ...
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1answer
127 views

Why is there such a big difference with these JPG file sizes?

I have 2 nearly identical JPG images that have been processed externally, but one file is much larger (in file size) than the other. I have been looking at all the metadata and embedded information ...
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5answers
2k views

What's the difference between colour space and bit depth?

I know that there are different types of colour space and that sRGB is the most common. Bit depth defines the variations of a colour channel, where (I think) 8 and/or 16 bits are the most common. ...
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1answer
172 views

Human perception in color mixing

Look at this image: 50% of its pixels are blue (0, 0, 255), 50% of its pixels are yellow (255, 255, 0). When I look at my computer display from a distance where I cannot distinguish the ...
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4answers
99 views

How to calibrate colors from photos for classification purpose (ICC profile)?

For a scientific study, I have to classify pictures of crop canopy in two classes: vegetation / soil. These picture are taken at several places, different times and date. The idea is to use the same ...
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4answers
202 views

What is the difference or relation between a Color Model and a Color Space?

What is the exact relation or difference between a color model and a color space? I find these two terms to be used interchangeably in some literature. Are they simply the same? Thanks!
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2answers
118 views

Lossy, linear, 8-bit DNG colorspace technical explanation?

I read a few articles about lossy DNG, and here is a very technical thread for example: http://forums.adobe.com/message/4132283 I get what lossy means, but the other important aspect is that it's 8 ...
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1answer
44 views

Color space encoding vs Color image encoding

Can someone explain to me, what's the difference between those to terms. I mean the space encoding I understand it as given the color space we define the depth (in bits) and value ranges that color ...
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3answers
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Displaying an 8bpp image on 30bpp hardware, what to do with the extra bits? [closed]

I am building some hardware with a graphical user interface and my images are stored with 8 bits per pixel (bpp) in RRRGGGBB format. However, my video chip expects 30bpp pixels (10 bits for each ...
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1answer
187 views

What is happening when I convert from a source color space AdobeRGB to a Canon photo paper profile?

I'm converting my photos in photoshop from the source space of Adobe RGB to the destination space of Canon PRO-100 LU 1/2 Photo Paper Pro Luster and when I do this my colors change very drastically, ...
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1answer
217 views

What's an easy way to batch assign (not convert) an ICC profile to .JPG and .CR2 Canon RAW files?

All of the files that comes out of my camera (Canon Rebel T3i) are not assigned a colorspace. Instead, all files the format IMG_XXXX.JPG/CR2 are implied sRGB and _MG_XXXX.JPG/CR2 are implied Adobe RGB ...
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2answers
872 views

Apple Aperture profile name (sRGB IEC61966-2.1 vs Camera RGB Profile)

I have a bunch of duplicate photos in Aperture. They came from separate iPhoto libraries. Some of the photos have the profile name sRGB IEC61966-2.1 and others Camera RGB Profile. Which should I ...
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2answers
124 views

Colour Management

I have a laptop. I have an Xrite colour display calibration tool. I have CS6. It may seem an idiotic question but in all my reading no one explains it simply. I profiled my monitor. It gave me a ...
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1answer
241 views

How is color represented in RAW formats?

I was browsing the forum and found this thread: Does the selection of sRGB or Adobe RGB in camera when shooting RAW ever matter? It makes sense that the selection of either sRGB or Adobe RGB as the ...
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2answers
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Adobe RGB to sRGB conversion, why does the color change?

When I convert my photos from Adobe RGB colorspace to sRGB for browsers, the color slightly changes and I’m bothered by it. I know that sRGB covers a smaller space of colors so I won’t get an exact ...
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3answers
1k views

Losslessly batch convert many JPEGs to sRGB?

Recently I came across a bunch of weird JPEGs; here's one of them. In Firefox 16.0.2 and ACDSee it looks much more vibrant: However in Internet Explorer 9/MS Paint/Paint.NET 3.5.10 (on Windows 7 ...
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2answers
13k views

Should I use “sRGB mode” on my computer screen?

I recently acquired the ASUS PA248Q screen for photo processing (and everyday use and gaming: I have just that one display). This display offers a "sRGB" mode. Right now the screen is configured to ...
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1answer
960 views

What is the color reproduction accuracy on mid-2012 non-Retina Macbook Pro-s and how applicable it is for photo editing?

What is the color reproduction accuracy (sRGB color space coverage) for Apple Macbook Pro non-Retina models from mid-2012 and how applicable it is for photo editing? I read that MBP Retina display ...
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1answer
393 views

Understanding Hue, and is there something else I should be using?

I am trying to isolate objects of a certain color in an image. Looking at this image, you can see that I have extracted the hue channel, and have filtered these values so that the closer a pixel's hue ...
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2answers
391 views

Does a YCbCr color picker exist for Windows or Unix?

Is there any YCbCr color-picker so that I can better understand the color space? For example, I want to get the range from the blue sky or from green grass. I need to know the value ranges to detect ...
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3answers
6k views

Does the selection of sRGB or Adobe RGB in camera when shooting RAW ever matter?

In talking to a colleague of mine yesterday, we got onto the subject of color spaces in digital photography. He's a Nikon buff, I use Canon (specifically, an EOS 50D); I don't know if that is relevant ...
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2answers
244 views

Should I perform the final color space conversion before or after final sharpening of an image?

When preparing an image for the web (or other media), the last two steps is usually to resize the image to the desired resolution and sharpen it at that resolution. However, when working in a ...
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3answers
410 views

What does the under/overexposure warning mean in image editing software?

We all know exposure warnings that a digital camera offers: If shows which parts are so bright or dark that there's no more distinction towards even brighter or darker areas possible. Meaning that ...
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8answers
8k views

What's the difference between Adobe RGB and sRGB and which should I set in my camera?

In my Canon 60D, there's a setting between Adobe RGB and sRGB. What's the difference and what should I prefer when shooting to RAW ?
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1answer
423 views

What is the photopic luminous efficiency function?

What is the photopic luminous efficiency function? Is it actually a the, or are there multiple such functions? Is it an absolute fact of nature or simply an agreed-on standard? If the later, who ...
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5answers
2k views

Why isn't the xvYCC color space seeing uptake for still photography?

For the last fifteen years, sRGB has been the primary standard for computer monitors (and for consumer-level printing). That's changing now, as wider-gamut LED-backlit monitors become common. Usually, ...
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3answers
792 views

How much of a difference do different color spaces make?

How much of a difference does it make to use one of the extended colorspaces vs. the normal sRGB? And what difference does it make? Are there situations where it is not important, and conversely are ...
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3answers
2k views

Are RGB numeric values equal to CMYK percentages?

are RGB numeric values equal to CMYK percentages?