Some Comments On Color

It turns out that color in the digital world is a rather tricky thing. You may be aware that professionals spend quite a bit more money on monitors for their computers than the average user. This in itself should be a tip-off that color is not an easy thing for a display manufacturer to get right. General consumer-grade displays sometimes get the color pretty close but too often it is noticeably wrong. It must be admitted that our fancy hand-held devices frequently fall into this category. I fretted quite a bit about the blue tint my first hand-held device imparted to my pictures. Then I got another device and the color was too yellow! What it is important to realize here is that it is not unusual for a device manufacturer to do some supplier-hopping depending on who currently has the best price on electronic components. This goes for the fairly expensive and color-critical display as much as any other component. As a consequence there is no way to predict what kind of color imbalance might exist in the future. So much for my initial idea of toning down the blue in my pictures to make them look right. Notice that this also means we are all pretty much stuck with "The Luck of the Draw" as to whether color will look correct on our particular device. One can hope things will improve with time. I admit that I am probably way more critical about this than the average user.

Another interesting color issue is the case of the color "violet." If you have ever looked carefully at a rainbow you may have noticed that violet's position is "outside" of the blue band (that is, on the opposite side from the rest of the rainbow.) This is a critical observation because in a digital world the colors of the rainbow are re-created for our eyes by mixing the output from red, green, and blue filters corresponding to the original red, green, and blue phosphors in the picture tube of a color television. With this setup a reasonable facsimile of any color between red and blue is possible by mixing these three primary colors in the correct proportion. However, the rainbow tells us that violet cannot be created by any mixing of these three colors - it is "outside" of their range of representation. So what happens when you photograph a violet flower? The camera will mix the red, green and blue as best it can and come up with the closest possible solution: straight blue.

A related issue is the observation that many people do not carefully discriminate between the colors purple and violet, but in reality they are two very different things. The color purple is a secondary color formed by mixing red and blue, but violet is itself a primary color out beyond blue (in the same way that the invisible color ultraviolet is out beyond violet.) Thus two flowers sitting side by side, one purple and one violet, might be perceived as looking very much alike. However, a picture of these two flowers will show a huge color difference, one purple as it should be and the other a startlingly incorrect blue! On the other hand I once took a picture of a rainbow with an older camera of mine and the picture shows a faint color outside of the blue band. Is it violet? Too my eye it looks purple. One thing a camera manufacturer could do is to make use of our tendency to not to discriminate between violet and purple and let a little violet light "leak" through the camera's red filter. If done carefully the camera could fool us into thinking we are seeing the violet in a rainbow by giving us a bit of purple. Pretty ingenious but not what we actually see when we look at a rainbow. By the way, this particular camera tended to render a blue sky with a tinge of purple, so if that was the manufacturer's intent they still had not got it quite right.

Finally, there will always be some variation in the hue of a picture dependent upon the light available at the time the picture was taken. One reason studio pictures look so good is that the photographer has absolute control of light in the studio. By contrast, one of my goals has been to do my flower photography "in place" if possible. Another goal has been to use natural lighting and consequently I try to avoid overuse of the flash. This means that when I'm working in a shady area the pictures can have a pronounced blue tint. It is probably worth mentioning that this blue tint is not wrong. The light in a shady area really is blue and the camera has faithfully recorded that. We tend not to notice this because our eyes adjust to situations and let us see colors as we expect them to look. When the color in a picture looks wrong I use computer software to correct the tint. However, if the color is really off there are limits to what can be done. In some cases I have been forced to use pictures that are less than optimal. This has usually only been the case for plants that grow in difficult situations. No doubt I will someday get around to re-shooting many of these pictures. After ten years this is still a work in progress.

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