Cameras RAW Files and Color Management

I mentioned yesterday that I still like my LX5 but was thinking about the X10 as a possible successor to it as my pocket camera. This must have been a little confusing as someone asked me if I thought it was "better". You see they were considering either the LX5 or the X10 as an upgrade to their aging P&S. Honestly I do not think it is better. Not for a moment. I think it is different - and I think it is overpriced as compared to the LX5 or the Canon S100. You may have noticed that I casually mentioned that I hoped the price would come down. It will but I don't know if it will before it is obsoleted with the X11 or whatever comes next.

The only two things that appeal to me in the X10 are the viewfinder (even though it's not very good from most peoples reviews) and the mechanical zoom vs the motorized zoom. I hate motorized zoom. Too slow and fiddly. So really the decision process might go something more like this for regular people looking for a decent point and shoot.

  • Really portable = Canon S100
  • Really great value and arguably better image quality with great lens, great OIS, good speed, good movies = Panasonic LX5
  • Insanely persnickity about a viewfinder and mechanical zoom with no real concern for value equation = Fuji X10

Let's face it they are all these point and shoots that take reasonable images. Not great but reasonable. If you happen to like the look of the output or the operational characteristics of one over the other that is probably the most important determining factor.

Liking the way an image actually looks is obviously paramount, this is photography isn't it? There are many factors - a lot of them subjective - in determining the look of an image. A really important one all else being equal is color. On that note why don't we kick off the whole discussion I keep bringing up about color and color management. I am going to deal with this piece by piece, step by step. Not as an end all be all how to but more just covering some bases that you may not have covered and as usual, inclucding some perspectives that are not the same old same old stuff you read all over the place. It's not going to be anywhere near a dogmatic by the numbers recipe that must be followed.

Consider the following images. You can download them if you want. In fact you probably should. If your browser is not color managed you have to. If it is, make sure that the color mangement features are turned on. The following JPEGS are not sRGB. They are ProPhotoRGB color space. All of them started off as RAW files, were shot under the exact same conditions, and are WB neutralized to the same gray patch.

  1. Exhibit A - Nikon D7000. Adobe ACR 6.6 w/ default profile. <div class="box "> </div>
  2. Exhibit B - Nikon D7000. Adobe ACR 6.6 w/ custom profile. <div class="box "> </div>
  3. Exhibit C - Panasonic LX5. Adobe ACR 6.6 w/ default profile. <div class="box "> </div>
  4. Exhibit D - Panasonic LX5. Adobe ACR 6.6 w/ custom profile. <div class="box "> </div>

The custom profiles were created with Xrite ColorChecker Passport. I primarily bought this just for the cool little plastic cased standard color charts as all of my other ones were larger and beat up. Typically I use it more for evaluation of cameras/film and other esoteric things. Then I get a feel for what kind of things I am most likely going to change one way or another for my taste. For most things I shoot I defintely do not plant the thing in a frame and make a profile as a matter of practice.

A couple of things to note. First off are the colors really all that different? Between the default profiles and the custom built profiles? Between the cameras? Well they certainly aren't night and day, are they? Which colors do you like better - your hard won super custom specials or the ACR defaults? The real question that needs to be asked is "what is going on here?".

First off - Adobe as well as other RAW software processors probably go through a process of creating profiles similar to what the Xrite software just did. In fact the ACR profile editor does pretty much the same thing with a whole lot more control. Second they probably tweak those profiles by hand to achieve some desired effect and that tweaking's intent is the same time after time, camera after camera. I can only guess at Adobe's or any other software developer's intent (which I will do but not right now).

What else is going on here? Let me answer that with a couple of screen shots. The reason for the scren shots is that although you may not see the exact colors I am seeing you will see what I am going to demostrate.

What the… The above image is a screenshot of my screen. Can you see all the grey blobs where colors should be? Good because the actual colors of the screenshot are going to be way off. The important part are the gray blobs. This is a "proof" with gamut warning turned on which replaces color with gray gook as seen for any color that cannot be represented by the target proofing profile selected. The color profile I selected happens to be the profile for the monitor I am viewing. The monitor I happen to be using is a little larger in gamut in most areas than sRGB. Nowhere near AdobeRGB let alone ProPhotoRGB.

What this means is you cannot actually evaluate those colors with the gray blobs by looking at them on this monitor. Most likely you can't on your monitor either. What a dilemma. Why the heck would we want those colors at all? They are very confusing if you can't actually see them aren't they. Ummm - yes. In fact my experience leads me to believe that even those color patches with a little bit of gray are highly suspect in terms of being represented well but that's another story. If you manipulate your images to any degree, especially the color of them you definitely want to do it in a larger color space than you are targeting for a bunch of reasons but you might also always want to proof your images against a reasonable target profile like sRGB to see what they will actually look like depending on how you convert them to that profile. We will get into this a bit down the road but not today.

Here is another reason you may and I do mean may want those out of "screen gamut" colors. Take a look at this:

This is the gamut comparison with Blurb's printing profile. Note that while it is worse in some color areas it can reproduce the actual yellows in the file better than we can see on this screen. Again remember than you cannot actually see that yellow on this monitor and most likely yours either. Blurb is not the greatest printing gamut either. Greatest as in widest. We'll go more into that down the road as I make my way through different topics on color over the next couple of weeks. You may want to take a look at this convienient and free way of evaluating various color spaces and profiles to get a feel for what is going on between your image file, your screen, and your prints.

Here are a couple of things to take away from this. While all the numbers are great… Do you really need to shoot a color chart and generate a custom by the numbers profile every time you shoot? Do you really need to generate one at all? Do you somehow like the colors better - are they that different? I suspect that the tweaking done by Adobe are to make the colors a bit less nuclear in the primarys for a lot of reasons, maybe to make them more pleasing to some panel of experts. Pleasing is good but pleasing is very different for different tastes and different subjects. Maybe the tweaking was done as a good compromise across subjects as a starting point.

Also note that you cannot evaluate all the colors by looking at them on your monitor. Get an idea of what colors those are for your camera and your chosen RAW work-flow. If you really want to get into the nitty gritty here down load the JPEG files above and measure the numbers as in the HSL paying close attention to the Hue to compare how different the color is between the default profile and the custom profile. Better yet compare how different (similar) they are between two vastly different cameras. Me - I don't bother shooting color charts to generate profiles by the numbers. I tweak my profiles to produce results that I find pleasing for the output I plan on producing. Especially for my chosen subject matter.

All of this is not intended to be prescriptive in any way. It is supposed to be illustrative, potentially educational, and absolutely get you thinking about important things like light, dynamic range and how an image actually looks on the intended display medium and not to worry too much about techno-crap. When you like or dislike the way colors look in an image it probably has far more to do with color relationships, gradation, and other factors rather than the actual hue. There are a couple of reference colors that are exceptions - skin being one. More on that another day with a focus on getting the output the way you want it consistenly. We had to start here at the begining with the color that is actually in your files and how to look at at them. Well at least how to tell if you cannot look at them.

One last thing until next time. Here are the same two color charts white balacned and processed by Aperture3's RAW processor.

  1. Nikon D7000 Aperture 3 default profile. <div class="box "> </div>
  2. Panasonic LX5 Aperture 3 default profile. <div class="box "> </div>

RB

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