Kind of Blue*

“Snow and sky, snow and sky, and the sky was even brighter, whiter, from the snow — and the snow sparkled with blue fires from the sky.”
    Zinaida Gippius

As I write this in January, 2020, there's plenty of snow high in the mountains around our home in western Montana. But where we live in the hills above the Mission Valley, at an elevation of 3700 feet (1130 m), we've not had much snow accumulation yet this winter, and down “in town” on the shores of Flathead Lake (elevation 2900 feet/884 m) the ground is mostly bare. It's been warmer than “normal” for much of this winter, resulting in rain rather than snow. I've got a couple of pictures in mind but I need solid snow cover to achieve my vision, so I'll have to wait and hope we get some decent snow down at lake level. Wishing for more snow on the valley floor has not endeared me to friends who live there, invoking comments I won't repeat here. I try not to question their choice to live in the mountains at this latitude if they don't like snow.

Curing The Blues

Digital camera sensors, like their film predecessors, render ice and snow in shadow as blue, sometimes very blue if the sky is cloudless (sunny). You'll find plenty of discussion on the Web about this if you're interested in the physics. There is, of course, a very strong blue component, but our brains filter that so snow and ice appear a more-or-less “natural” white to us. We perceive clean snow as white on sunny days, white on cloudy days, white at twilight, etc. But our cameras, whether exposing film or digital sensors, have no such built-in mediator, resulting in blue shadows.

In photos I find this blue to be unrealistic and distracting. Fortunately, Photoshop, Lightroom and (probably) other photo editing software make it fairly easy to “fix” this so snow and ice in shade can be made to look more neutral, as we see it. While I don't usually make adjustments to alter the look of the subjects in my pictures, I consider this one of those cases where such adjustments compensate for limitations of the equipment used to capture the photo. These adjustments make the picture look as I remember the scene when I made the image. This is just my personal preference; you may of course feel differently and prefer blue snow in your photos. I see it in lots of pictures.

If you've set your camera to make jpegs (or if, in the case of most smartphone cameras, jpeg is the only format available) you may be able to limit this affect a little bit by changing a setting, perhaps to something like “shade” or “cloudy” or with phones like my current Pixel 3a simply let the system's “AI” interpret and render the image as it thinks it should be, and hope for the best.

If you shoot in raw mode you might be tempted to choose a color temperature setting like “shade” or “cloudy,” as mentioned above, or dial in a custom color temperature. Doing so embeds data in the raw file that will inform your raw processing software (Photoshop/Camera Raw in my case, but Lightroom and most others have similar features) when you open the raw file; if you're shooting raw and set the camera for “cloudy,” when you open that raw file in Camera Raw (or Lightroom's Develop module) it will show “cloudy” in the White Balance box. But in the end it makes no difference how you set the color temperature when shooting raw; you can change in post-processing to whatever you want for the desired affect. Disagree? Test it! Make some exposures with your camera set to auto-white balance, and then make the same exposures using other color temperature settings. Open the individual files in your raw processor and look at the color temperature values, compare them to the exposures made in auto-white balance.

You can, however, use your raw processing software's adjustments to reduce or eliminate the blue in the shadows. I generally don't, as I prefer to make such adjustments using layers in Photoshop. I think this provides more tools and more flexibility, including the ability to fine-tune by tweaking the opacity of any adjustment layers; a scalpel rather than a box cutter. Just my opinion, of course. Every photographer I know has his or her own preferred tools and methods for optimizing their work.

Sometimes a picture looks best when a little (or a lot!) of the blue is left. This can help impart a feeling of cold which in many cases is the point of the picture, as in the one above. And some photos, such as those of Glacier faces after a calving event, really are very blue because air bubbles have been compressed out of the ice as the glacier formed. Those newly-exposed faces become whiter over time as they absorb oxygen. In other pictures it may be best to take those blues all the way to gray; I think this works well in snow/ice photos in warm light, but again, that's my opinion and certainly doesn't apply to every picture. Luckily our software lets us test and experiment and adjust (and undo) endlessly, with the goal of making pretty images, feeling kind of blue, or not, as you like.

*Apologies to the late, great Miles Davis, for swiping the title of his classic 1959 album.

January, 2020

All products and brand names mentioned are trademarks or registered trademarks of their respective owners.