Sunset overlooking the Front Range from Longmont, CO in a stable atmosphere.
Introduction
The purpose of this class is to visualize flow phenomena. For this image, we were tasked with taking pictures of clouds. Due to the many variables present in the physics of clouds, there were many distinct images submitted. For my submission, I photographed altostratus clouds at sunset.
Circumstances of Image
This image was taken in Longmont, CO at a friend’s house that overlooks the Front Range. I was facing west at the time and had the camera angled parallel with the horizon. It was taken on October 8th, 2016 at 6:32 pm. The weather was fair that day, with temperatures in the mid 60’s.
Cloud Physics
The sky to the east was fairly clear, indicating an orographic influence on the cloud formation. The atmosphere was stable, with a cape indication of 0, as can be seen in the Skew-T graph in Figure 1. Based on observation, I would guess the clouds are altostratus. The dew point was close to 11,000 meters and 5,800 meters. Altostratus clouds typically form between 2,000 and 7,000 meters [1].
Figure 1: Skew-T from the University of Wyoming.
Altostratus clouds usually form right before storms. In this case, there was no storm in the forecast. The clouds could have been formed due to warm air rising due to the mountains. This warm air is then cooled and condenses around the dew point level, which in this case is about 5,800 meters.
Photographic Technique
Figure 2 and Figure 3 show the image before and after post processing, respectively. I cropped the bottom to focus in on the clouds, while supplementing the image with them for context. Additionally, I adjusted the contrast and exposure to bring out the colors of the sunset. This in turn, darkened the mountains.
Figure 2: Original image.
Figure 3: Final, edited image.
The table below shows the camera specifications and settings for the image.
| Camera | Nikon D3200 |
| F.O.V. | ~2-3 miles |
| Distance: Mnts to Lens | ~4-5 miles |
| Focal Length | 95 mm |
| F-Stop | f/5 |
| Shutter Speed | 1/400 sec |
| ISO | 400 |
Conclusion
I was very happy with the outcome of the image. Often sunset pictures feature pinks and reds, but mine is mostly blues and yellows. Also, I really like silhouette pictures, and was happy to finally try my hand at capturing this. I wish that the details of the clouds were more defined. I was hoping the contrast would bring them out, but it did not happen as much as I would have liked. Overall, I really like the image.
25 Comments. Leave new
Very nice. I like the added composition from the volcanic like contrail in the center of the image. Good job in post processing.
Nice range or colors from the orange to blue. I like the silhouetted mountains at the bottom.
I love this image! I really like all of the colors in the sky, from the yellows and oranges in the distance to the darker grays in the clouds that the sun has already set upon. It creates a vibrant range of contrast in colors. Looks like a fantastic evening in Longmont!
The transitional palette of colors is what I find most appealing in this image. I am curious what the image would look like if you cropped the bottom of the image up, simply to remove the amount of black space below the colorful cloud formations.
Art: I really like the color contrast of the bright highlights of color on the clouds and the dark background of the mountains, I think the dark silhouette of the mountains adds substantially to the quality of this piece.
Flow: The flow is quickly understandable and easily recognized.
Photographic technique: The focus of the clouds is great.
Beautiful sunset, the colors are absolutely gorgeous. The frame on the bottom is beautiful and gives a nice contrast. Great quality and focus
I like the color in this photo. I like how the foreground seems a bit darker and the background is more illuminated, it brings a lot of contrast to this photo.
– Great photo I like the colors, not over saturated or anything.
– I really like how the contrails how one is more vertical and the other is horizontal it really compliments the image.
1. Great artistic image of a sunset.
2. The physics are well shown.
3. The photographic technique is very nice.
Great use of the silhouette of the mountains. Colors are great.
I wish the photo was slightly brighter above.
Colors are great, and the mountains provide a good contrast.
Great image shows the combination of sunset and cloud. Very good catching!
Great contrast between the mountains and the sky; not just in color, the difference in sharpness is appealing. You have some really interesting shades of purple and yellow going on.
Nice pastel colours and there is great contrast with the black horizon. Not sure if the contrail adds to the picture, did you consider removing it? Overall, very nice picture.
Orange and blue work together so well in photos, and this one is no exception! Great colors, nice relaxed vibe, and I like how sharp your mountain silhouette is
This sunset is gorgeous. Straight up beautiful. I am very glad that we are able to see a sight like this. With that said, I am curious as to the color change of the sun as it is setting. When the sun sets along an even horizontal axis, there is usually a brief color change along the spectrum with the last color visible being green. But this is usually along coastlines. The artistic merit here is breath-taking because dark blue and light orange are excellent contrasts of one another. This photo was great.
A lot of color spread throughout the image. Nice high, thin alto-stratus clouds. Great contrast. God job blacking out the bottom so there are no distracting elements.
so beautiful ! great color and contrast!! nothing bad to say
I love the color gradient of the sky, transitioning between the cool blues and warm yellows of the sunset. The lighting layers on the cloud to the right is awesome.
Wow! Nice coloring, beautiful image. The mountain silhouettes are nice, interesting clouds.
Really awesome colors in this image, they are very vibrant! The silhouette of the mountains creates a nice visual for the bottom of this picture. Cloud structure is very unique.
I enjoy the sunset colors with the small openings in the thin clouds. The blacked out mountains adds a nice contrast to the orange.
I love the color of the sunset as it contrasts well with the blue sky.the flow can we seen and i like the contrails.
I like the contrails that are included in the photo. the vertical plume in the middle reminds me of smoke rising out of a chimney. The colors are really nice in this photo.
Excellent contrast between the mountains and the sunset. Cool to have the contrails in the image. Yellow on the inner clouds adds a nice effect.