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Eclipsed Moon Over Wyoming

Explanation: A setting full moon rarely looks like this. Monday morning just before a fully lit Strawberry Moon dropped behind the Absaroka Mountain Range near Cody, Wyoming, USA, the shadow of the Earth got in the way. A similarly setting partial lunar eclipse was visible throughout most of North and South America, while simultaneously the same partially darkened moon was visible throughout eastern Asia. Pictured in the foreground is a snowbank formation known as the Horse's Head off a tributary of the Shoshone River. Lunar eclipses occur about twice a year, and the next one -- a penumbral eclipse -- will occur in late November.

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"Pictured in the foreground is a snowbank formation known as ..."

I guess it depends upon what one means by "foreground."

Photographically, is not the foreground Castle Rock (APOD link), with the Horse's head snowbank in the mountains in the middle ground?

Amazing image!

Nice!

"I wanna be a cowboy"

A serene scene with a beautiful moon!

There's something about this image that is not easy for me to explain. In Adobe's Camera Raw, there is a slider for adjusting the clarity of an image. What it does is locally increase contrast around edges. The results can be strikingly good but they can also result in this dark halo around bright objects. That's what is happening to the moon in this photo. It also produces a light halo around darker objects, such as the mountains and horizon. Most people probably do not notice. However, since I know about this, I can't not see it! It's a silly thing to be bothered by.

Beautiful photo. Peaceful.

geckzilla wrote:There's something about this image that is not easy for me to explain. In Adobe's Camera Raw, there is a slider for adjusting the clarity of an image. What it does is locally increase contrast around edges. The results can be strikingly good but they can also result in this dark halo around bright objects. That's what is happening to the moon in this photo. It also produces a light halo around darker objects, such as the mountains and horizon. Most people probably do not notice. However, since I know about this, I can't not see it! It's a silly thing to be bothered by.

Also...it might be that if you look at the image at full resolution, you'd notice that it has been altered with a painterly filter effect (that comes with PhotoShop, e.g.). So the edge effect you see maybe an artifact of being 'artistic'.

What is a "snowbank formation"? I've tried to find out but have not readily been able to get the answer (I assume it is a geological term). Thanks for any help.

scr33d wrote: Also...it might be that if you look at the image at full resolution, you'd notice that it has been altered with a painterly filter effect (that comes with PhotoShop, e.g.). So the edge effect you see maybe an artifact of being 'artistic'.

I disagree with this assessment. The texture is noise from the exposure. The exposure, blacks, hue, saturation, or curves (there's a lot of adjustments that can be made) of the image may have been changed to make the bottom green area take on a canvas texture as a side-effect but I don't see any "artistic" filters. And certainly even if one of those filters were run it would not have caused the contrast halos. There's nothing that causes local contrast halos but the clarity slider, which may have another name in any other editing programs. I'm only aware of Adobe's Camera Raw.

geckzilla wrote:There's nothing that causes local contrast halos but the clarity slider, which may have another name in any other editing programs. I'm only aware of Adobe's Camera Raw.

Most sharpening algorithms produce contrast halos. Also, in an image like this that is likely to need its dynamic range adjusted, areas might have been masked, feathered, and individually adjusted (for instance, the Moon). This can also lead to that contrast effect you observe. Nothing wrong with any of that, of course, particularly if the intent was to produce an image that captures the visual impression of the event (which a simple camera image will not necessarily do).

geckzilla wrote:

scr33d wrote: Also...it might be that if you look at the image at full resolution, you'd notice that it has been altered with a painterly filter effect (that comes with PhotoShop, e.g.). So the edge effect you see maybe an artifact of being 'artistic'.

I disagree with this assessment. The texture is noise from the exposure. The exposure, blacks, hue, saturation, or curves (there's a lot of adjustments that can be made) of the image may have been changed to make the bottom green area take on a canvas texture as a side-effect but I don't see any "artistic" filters. And certainly even if one of those filters were run it would not have caused the contrast halos. There's nothing that causes local contrast halos but the clarity slider, which may have another name in any other editing programs. I'm only aware of Adobe's Camera Raw.

google 'photoshop unsharp mask' to see adjustment to create your 'halo' effect.
google 'photoshop filters' for the almost uncountable number of artistic filters out there, including filters that simulate noise.

I am aware of both of those and will continue to disagree on the grounds that it is more unlikely than it existing in the original exposure. I agree with Chris sharpening could have been done manually. The tools in the Camera Raw program are much more efficient at it, though.

...Either way, I did not mean to criticize the image. It's merely an observation -- one I see many times in APODs and never mentioned because it is niggling.

Chris Peterson wrote:

geckzilla wrote:There's nothing that causes local contrast halos but the clarity slider, which may have another name in any other editing programs. I'm only aware of Adobe's Camera Raw.

Most sharpening algorithms produce contrast halos. Also, in an image like this that is likely to need its dynamic range adjusted, areas might have been masked, feathered, and individually adjusted (for instance, the Moon). This can also lead to that contrast effect you observe. Nothing wrong with any of that, of course, particularly if the intent was to produce an image that captures the visual impression of the event (which a simple camera image will not necessarily do).

In particular, having personally tried to capture similar scenes with subjects of varying brightnesses (in this case, the sky, the moon, and the ground), and post-processing them to get closer to the desired ratios, I suspect he ended up with an exposure that left the sky, and particularly ground, darker than desired, or than the human eye perceives them in relation to the moon. The human eye and mind simply have an amazing ability to adjust unconsciously for different brightness levels like this, so we perceive such scenes much differently than a camera does.

So he probably had to increase the brightness of the sky, which as a side-effect enhances visible noise, and left a slight dark halo around the moon where he or a Photoshop filter feathered the effect, and increase the brightness of the ground even more.

Then the foreground probably looked a little dull, because he expanded a relatively small part of the brightness range into a bigger range, so he would have done some local contrast enhancement (one of several types of HDR processes fundamentally similar to an unsharp mask) to make the foreground look more natural, which also resulted in a faint light halo around Castle Rock.

Lastly, he would have wanted to use noise reduction to try to make the noise less distracting, which tends to smear fine details and is evident as a sort of water color effect on the grass and rocks.

This is a tough image to take. If the moon is eclipsed at exactly the right time, the sky will be bright enough to complement the moon properly. However, the moonlight and diffused sky light together do not provide enough light for the ground, so it's still guaranteed to be dark.

Meanwhile, during a lunar eclipse, the sun is below the horizon, and even if it weren't, it would cast shadows that make the foreground look harsh, and filtered through the dust in the lower atmosphere, would add a sharply contrasting red hue to the ground.

So the photographer had to know what his ultimate goal was in getting the initial exposure in a range he could use, then put quite a bit of effort into post-processing the image to give us this final version. He arrived, in my opinion, at a very good representation of how we perceive the relative brightness and colors of these objects, even though it came at the cost of foreground details and a few processing artifacts.

DavidLeodis wrote:What is a "snowbank formation"? I've tried to find out but have not readily been able to get the answer (I assume it is a geological term). Thanks for any help.

I apologise for repeating this query but as there has been no respone so far I thought I would ask it again. All the definitions that I've found for snowbank (so presumably also applying to 'snowbank formation') is that a snowbank is a mound of snow and nothing else. Unless I am badly misinterpreting the image it does though not look to me like a mound of snow. I would therefore be grateful if someone could please let me know if a snowbank formation has a particular meaning other than a mound of snow. Any help will be greatly appreciated.

DavidLeodis wrote:I apologise for repeating this query but as there has been no respone so far I thought I would ask it again. All the definitions that I've found for snowbank (so presumably also applying to 'snowbank formation') is that a snowbank is a mound of snow and nothing else. Unless I am badly misinterpreting the image it does though not look to me like a mound of snow. I would therefore be grateful if someone could please let me know if a snowbank formation has a particular meaning other than a mound of snow. Any help will be greatly appreciated.

It can be nothing more than a mound of snow. It can also be a snow formation, typically on a mountain face, that appears to look like something interesting. In this case, it is an annually cyclic snowbank that looks like a horse. It is only visible when there is the right amount of snow; too little or too much and the illusion is lost. There are famous snowbanks like this in mountains all over the world.

Thank you Chris for your help, which is much appreciated.

I thought it did not look like snow, which is why I had wondered if there was a specific geological meaning of a 'snowbank formation' (as in rock formations). Without being informed I would therefore have never thought it was just a mound of snow! I wonder if I was the only person not to realise that? perhaps that I could not tell but I'm still ing.

Well, on the subject of geology...the Shoshon river mentioned in the image gives geologists shoshonite, a high potassium basaltic rock that reveals lots about subduction zone processes!