Tag Archives: flow

Photographs: Nature, Photographs: Northern California, Photographs: Sierra Nevada, Photographs: Yosemite

Tuolumne River Below Glen Aulin, Morning

1 Comment
Tuolumne River Below Glen Aulin, Morning
Tuolumne River Below Glen Aulin, Morning

Tuolumne River Below Glen Aulin, Morning. Yosemite National Park, California. September 16,2011. © Copyright 2011 G Dan Mitchell – all rights reserved.

Early light on morning clouds above the Tuolumne River Canyon below Glen Aulin, Yosemite National Park.

This is the same bend in the Tuolumne River, located below Glen Aulin and before the river descends toward Waterwheel Falls and eventually the abomination of Hetch Hetchy Reservoir, that was shown in a photograph of late afternoon light that I posted here a few days ago. This time it was early morning. We had been up well before sunrise and had wandered off in various directions to find early morning photographic subjects. My main goals were the cascading water along the edge of this section of the river (a bit of which is visible in the lower portion of the frame) and a granite bowl to the right of this view. As I came over the rise above this area before descending I saw the beautiful sparse clods to the west, probably extending to the edge of the Sierra and still with pastel colors from dawn light.

A technical observation about this photograph. This scene presented a technical challenge in the form of an extremely wide dynamic range between the bright and red-saturated first direct sunlight on the ridge at upper left and the much darker areas of forest in shade along the river and in the foreground. With a digital exposure, in a scene like this one, the primary rule for me is “don’t blow out the highlights.” If I had overexposed the sky the clouds would have turned into pure white, texture-free blotches and that bit of early sun on the rocks would have lost detail and taken on a very strange coloration. However, an exposure that protects the highlights in a scene like this one can leave the shadows nearly black. While it is possible to “fix” that a bit in post, the result is not necessarily very good when the dynamic range is very large. One “traditional” solution would have been to use a graduated neutral density filter (or “GND”) that blocked some of the brightest areas at the top of the frame while not affecting the lower 2/3 or so. But I don’t use them, and in this case the result would not have been totally wonderful since the same filtering that would reduce sky brightness would also make the large granite dome at the right end up nearly black at the top.

So instead of filtering at the time of exposure, I decided that I would use the roughly comparable, but more flexible, “exposure blending” techniques in post. With that in mind I made several photographs at different exposures – some at shorter shutter speeds to avoid the blown out highlights and others at increasingly slower shutter speeds to reveal the shadow detail that my eyes could see but which the camera otherwise could not. During the post-production phase, I selected two of the exposures, one that was as bright as possible but without blowing out the sky and sunlight, and the other two stops lighter to reveal that shadow detail in a way that seemed consistent with what I recall the scene actually looked like. The two source images were carefully adjusted during raw conversion and their two layers carefully aligned. With the darker image (the one with the “good” sky) on the top, I began to “paint” out the mask to reveal the details of the foreground forest, river, and rocks. (In answer to the expected question, this is not the same as HDR. That is a more or less automated process that works in a different way. Exposure blending is typically a manual process that relies a great deal on the photographers judgment and recall of the actual scene.)

G Dan Mitchell is a California photographer whose subjects include the Pacific coast, redwood forests, central California oak/grasslands, the Sierra Nevada, California deserts, urban landscapes, night photography, and more.
Blog | About | Flickr | Twitter | Facebook | Google+ | 500px.com | LinkedIn | Email

Text, photographs, and other media are © Copyright G Dan Mitchell (or others when indicated) and are not in the public domain and may not be used on websites, blogs, or in other media without advance permission from G Dan Mitchell.

Photographs: Nature, Photographs: Northern California, Photographs: Sierra Nevada, Photographs: Yosemite

Boulders, Cascade Creek

Leave a comment
Boulders, Cascade Creek
Boulders, Cascade Creek

Boulders, Cascade Creek. Yosemite National Park, California. June 18, 2011. © Copyright G Dan Mitchell – all rights reserved.

Granite boulders deflect the turbulent flow of Cascade Creek as it descends to the Merced River, Yosemite National Park.

This photograph is another in my continuing study of the boulders and flowing water of Yosemite’s Cascade Creek. I made this photograph fairly early in the morning on the weekend when Tioga Pass opened this year. I arrived before the scheduled 8:00 a.m. opening of Tioga Pass Road and decided that it would be more interesting and useful to photograph this subject than to wait in line so that I could be on my way over the pass at exactly the moment the road opened, especially when the morning brings shaded, diffused light to this cascade.

As I repeatedly photograph this subject, I begin to know it much more thoroughly. Partly it is a matter of understanding the seasonal and even daily ebb and flow of water and light at this place, but it is also a process of becoming very familiar with smaller details of the scene. When I first photographed here this rock outcropping was something that I occasionally worked to minimize in some compositions, but it has since come to be an interesting subject on its own. It extends into the torrent, forcing the water to flow around (and partially over, in high water) before dropping steeply to the right, running into other rocks, and making a quick and turbulent left turn before heading over another drop. Because it sits in the middle of all of this wild water, it is often covered with water and this water reflects the light of the open sky beyond the shaded confines of this narrow canyon.

G Dan Mitchell Photography
Flickr | Twitter (follow me) | Facebook (“Like” my page) | LinkedIn | Email

Text, photographs, and other media are © Copyright G Dan Mitchell (or others when indicated) and are not in the public domain and may not be used on websites, blogs, or in other media without advance permission from G Dan Mitchell.

Photographs: Nature, Photographs: Northern California, Photographs: Sierra Nevada, Photographs: Yosemite

Impossible Tree Falls

3 Comments
Impossible Tree Falls
Impossible Tree Falls

Impossible Tree Falls. Yosemite National Park, California. June 19, 2011. © Copyright G Dan Mitchell – all rights reserved.

“Impossible Tree Falls” in full early season flow, fed by the runoff from a very heavy snowpack, Yosemite National Park.

I don’t know if this is really called Impossible Tree Falls, but I like the name and I’m going with it. My guess is that the reason for the name might be two-fold. First, the tree does grow right in the middle of this roadside water fall. It must be an interesting few weeks each spring when this tree wakes up to find itself in the middle of a raging water fall, since the rest of the year things are much calmer. Second, the trees seems to grow on nothing but bare rock. It is hard to see in this mist-covered and back-lit image, but it looks like the tree is rooted in solid rock.

For a person who likes to occasionally think of himself as something of a back-country photographer, it is almost embarrassing to admit that this waterfall is right next to Tioga Pass Road. I’ll be honest – I parked my car in a pull-out on the opposite side of the roadway and probably never moved more than 10 yards from there. To add insult to injury, at a couple of points I had to stop shooting while passing recreational vehicles interfered with the view! ;-)

But none of that makes the tumultuous little waterfall any less impressive. It appears above the road, where it seems to come out of a flatter forest area, and then it abruptly tumbles down a very steep rocky incline, twisting and turning around boulders – and one solitary tree.

G Dan Mitchell Photography | Flickr | Twitter (follow me) | Facebook (“Like” my page) | LinkedIn | Email
Text, photographs, and other media are © Copyright G Dan Mitchell (or others when indicated) and are not in the public domain and may not be used on websites, blogs, or in other media without advance permission from G Dan Mitchell.

Photographs: Nature, Photographs: Northern California, Photographs: Sierra Nevada, Photographs: Yosemite

Boulders and Spring Torrent, Cascade Creek

4 Comments
Boulders and Spring Torrent, Cascade Creek
Boulders and Spring Torrent, Cascade Creek

Boulders and Spring Torrent, Cascade Creek. Yosemite National Park, California. May 7, 2011. © Copyright G Dan Mitchell – all rights reserved.

Runoff from spring snow melt rushes over boulders of Cascade Creek, Yosemite National Park.

I recently posted the black and white version of this photograph of Cascade Creek in full spring flow. I am still undecided about which I prefer. I haven’t printed either as of the date of this posting, and the results of that further work may help me decide.

The color version of this photograph posed a series of post-processing questions and problems that others who have worked with a scene like this one can probably imagine. The creek descends through a narrow, rocky gorge at this point and I photographed it early in the morning before any direct sunlight was able to reach the water. Benefits of shooting at this time included the softer light, which tends to both throw some light into the shadows and to soften the brightest highlights. This also permits a longer exposure which allows the water to blur a bit and express the wild motion of the creek. However, since the primary source of light was the open sky, the camera “sees” a very blue scene. (Our visual system compensates for this, so it doesn’t look as blue as it really is when you are on the scene.)

There are several ways to deal with the color balance issues that this situation creates. You could just “go with the blue,” and I’ve seen photographs done that way. I’ve even seen some in which the photograph amped up the saturation and ended up with something very blue. In general, that’s not my thing! I’m most often looking for something that seems “believable” – it may not be objectively accurate, but I intend it to be “subjectively accurate.” With this in mind, my first instinct was simply to warm the color balance in order to move away from the blue cast and toward a warmer one.

My immediate impression was that this was an improvement, and I worked with this interpretation for several days – but something about it didn’t sit quite right with me. (This is perhaps one reason that I also worked with the black and white rendition in the meantime.) Eventually I did some comparisons between the “warmed up” version and the original… and neither seemed like what I was after. The overly blue original looked garish but the overly warm version seemed artificial. I tried some other approaches and finally discovered that because the blue was so intense that I could simply desaturate it – more than you might think – and keep the “colder” coloration without letting it overwhelm the image.

G Dan Mitchell Photography | Flickr | Twitter (follow me) | Facebook (“Like” my page) | LinkedIn | Email
Text, photographs, and other media are © Copyright G Dan Mitchell (or others when indicated) and are not in the public domain and may not be used on websites, blogs, or in other media without advance permission from G Dan Mitchell.

Canon EOS 5D Mark II (at B&H)
Canon EF 70-200mm f/4 L USM at 126mm (at B&H)
ISO 100, f/16, 1/8 second