It seems a long time since I last wrote a blog article, and even longer since I last did one for Image of the Week; a Critique. A crazy last couple of weeks with an ankle injury and a dead hard drive have been higher up my priorities (“how dare you?” I hear you ask!).

I promise to update on the hard drive at a later point but I feel it is my duty to now announce the latest installment in the Image of the Week; a Critique series -titled Ataraxis, taken from the gallery Darkness. I hope this article makes up for my recent absence!

During Thanksgiving 2012 on a trip to the Mount Shasta region of Northern California, I stumbled upon an upland meadow only a stone’s throw from the main downtown street of the pretty little town of Mount Shasta (see map below). When I found the meadow, complete with a friendly cat who patrolled the place like he owned it, it was sunset and I dutifully watched the sun set upon the volcano; a beautiful sight in itself. Vowing to return in the dark after watching the tree lighting ceremony, I had the idea of making a star trail image with the volcano as a centerpiece. Star trail images are not my expertise, requiring that they do a level of patience and a propensity to not get bored or cold, both essential traits in this domain. Never-the-less, night-time and star trail pictures fascinate me, much for the reason that there is an ethereal quality to night-time images where the light is subdued, adding an other-worldly quality to scenes that otherwise in the daytime under the sun we recognize more. Furthermore, night-time gives the photographer a chance to capture an extended piece of time in the same image, which is mostly impossible in bright daylight without over exposing.

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Returning as I did after dark, I was disappointed to note how bright the moon was, given it was several days from full moon. Additionally, there was a lot of high cloud around which meant that the light from the moon was spread over the sky further obscuring the visibility of stars. If that wasn’t enough, the expected light pollution from being within a town also hampered the view of the sky, with the clouds also reflecting that too.

Not to be deterred, and given that returning to Mount Shasta anytime soon would be unlikely, I forged ahead with an attempted star-trail photograph. The method of these kind of images is to take a series of images to be later stacked in post-processing and carefully blended. Trying to achieve a star-trail in just one photograph is near on impossible. This is because star-trails take a long period of time to capture, and in-camera data buffering typically becomes overwhelmed by this, not to mention what if you spend 1 hour taking a photograph to find out you got something wrong? Also, other aspects of the image have to be considered; any artificial lights will over-expose in many cases, and in this particular scene, a snow-capped mountain was reflecting strong moonlight, also risking the chances of over-exposure. Being one who does not like to overly post-process images, I had to balance this with the technical challenges before me.

Other technical challenges presented themselves in the aperture and film speed (ISO) I should choose. Not stopping down enough would mean the depth of field could be too shallow or important elements out of focus, but too much would result in longer exposures and dimmer light from the stars being picked up. Too low an ISO and the same issue with dim light pickup of the stars would be present, and too high of an ISO would mean a lot of noise (graininess) to the image. A few test shots later I decided I had the right settings and I set loose the bulb shutter on my camera for a series of 3 minute images. Later I would post-process the images at home.

Post-processing was a real drag. On initial review of the photographs I had taken I was very disappointed. The moon and high cloud had really washed out the sky obscuring the brightness of the stars, and moonlight reflected on the snow had also over-exposed the peak of Mount Shasta. Also, several of the later images had to be discarded due to fogging of my lens. It was cold when taking the photographs and inevitably dew formed on the camera body and lens as time passed. discarding these images meant the star trail would have shorter concentric circles.

Plowing on with salvaging the shot, I stacked and blended the remaining nine usable photographs, paying particular attention to emphasizing the light of the stars, and also not over-exposing the mountain. Cropping on the right, ‘East’ side of the image was required to remove a very bright and diffused Jupiter, and some noise reduction and a few dabs of the healing brush to remove a couple of dead pixel artifacts from the sensor of my aging camera.

Overall, I am very pleased with the result given it was my first serious attempt at a star-trail image. By no means is it perfect though. Returning during a partial moon minus the high-cloud would work wonders for improving this photograph. Highlighting the snow-capped volcano is a must and should not be overlooked, but a full moon is just too much, though it does help to highlight and add detail to the foreground. Also re-locating to a vista where the North Star is above the volcano peak so that the star trails would revolve around the mountain would add an obvious balance missing from this shot. On a technical level on improving this particular shot, given the limitations of when I happened to be there and the lack of local knowledge of better viewpoints, then shooting one shorter image to get a correctly exposed mountain which could be blended in, would be an obvious solution.

Hopefully soon, I can get out into the back-country again and attempt another star-trail with a further improved result. However, let me know your thoughts on this image and how you would have shot it; after all, I am still learning (which is a lifelong journey). I would also love to see your photographs if you have any, so please link to them in your comments!

Technical Details:
Aperture: f/6.3
Exposure Time: 9 images at 180 seconds each
ISO: 800
Focal Length: 13mm
Post-process: stacking, blending, levels, dodge, burn, noise-reduction, healing-brush, crop