APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

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Expand view Topic review: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by neufer » Sat Nov 21, 2015 8:32 pm

http://www.washingtonpost.com/wp-srv/style/longterm/books/chap1/dinosaur.htm wrote:
Dinosaur in a Haystack
Reflections in Natural History
By Stephen Jay Gould

Chapter One: Happy Thoughts on a Sunny Day in New York City

<<Nature ... mocks our attempt to encase her in a Platonic straitjacket by establishing an almost laughably fortuitous reason for some apparent, highly visible regularities that have played a major role in human history. In my favorite example, much discussed by many commentators, solar and lunar eclipses produce a gorgeously precise and tight fit (as the moon's shadow snugly covers the sun and vice versa)>>

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Chris Peterson » Fri Oct 16, 2015 4:34 am

mproebstle wrote:Perhaps some of the post processing which gave rise to the 'halo effect' as proposed below is at play here as well?
I really think scatter off clouds explains it the best.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by geckzilla » Fri Oct 16, 2015 12:53 am

mproebstle wrote:Perhaps some of the post processing which gave rise to the 'halo effect' as proposed below is at play here as well?
I think the slightly brighter sections are lunar halo and moonlight filtering through the mentioned clouds. The darker part might be real too but it is probably emphasized by an unsharp mask and likely some processing artifacts were introduced as a result of this as well, but those are all very regularly defined. The irregular shape around the eclipsing moon segment which looks something like a harpoon or an arrow is going to be the time lapse of moonlight through clouds.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by mproebstle » Fri Oct 16, 2015 12:06 am

Perhaps some of the post processing which gave rise to the 'halo effect' as proposed below is at play here as well?

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Chris Peterson » Thu Oct 15, 2015 3:58 am

mproebstle wrote:Chris,
See 2015 October 14: A Gegenschein Lunar Eclipse
So maybe what I'm pointing out could be the Gegenschein that became resolved in this photo as well?
Nope, not a chance. The gegenschein is very dim. It was captured in the other image because we have a long exposure while the Moon was eclipsed. The integrated sky background in this image is orders of magnitude brighter. There's absolutely no way such an image could capture gegenschein. (Note that you don't see star streaks, because they, too, are lost in the noise of the bright sky... and stars are a lot brighter than gegenschein.)

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by mproebstle » Wed Oct 14, 2015 11:14 pm

Chris,
See 2015 October 14: A Gegenschein Lunar Eclipse
So maybe what I'm pointing out could be the Gegenschein that became resolved in this photo as well?

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by geckzilla » Mon Oct 12, 2015 8:24 pm

It occurs to me that not everyone is necessarily familiar with what I mean by halo so I'm posting an example image. On the left is a painting simulating a horizon. On the right, a rather harsh unsharp mask has been applied. You can see how it increases the contrast of the edges. Ideally you don't want those halos to be visible but often many people go a touch overboard with it.
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Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by geckzilla » Mon Oct 12, 2015 8:01 pm

There was definitely some post processing to boost the clarity on this. You can see it most easily along the silhouette of the hills at the horizon in the way it darkens the dark edge and lightens the light edge to create a halo effect. It makes me wonder how much of that dark halo around the moon is really there.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Chris Peterson » Mon Oct 12, 2015 2:26 pm

mproebstle wrote:Hmmm.....I'm not convinced. I would think that as the Moon transitioned into conditions of less and less reflected sun light along with the long duration photography format presented here would have been the perfect situation to capture something otherwise hidden. The sky appears to be pretty clear...evidence of thin clouds would have certainly showed up.
Evidence of thin clouds did show up- as scattered light from the Moon during a long exposure!

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by mproebstle » Mon Oct 12, 2015 2:24 pm

Hmmm.....I'm not convinced. I would think that as the Moon transitioned into conditions of less and less reflected sun light along with the long duration photography format presented here would have been the perfect situation to capture something otherwise hidden. The sky appears to be pretty clear...evidence of thin clouds would have certainly showed up.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Chris Peterson » Sun Oct 11, 2015 2:37 pm

mproebstle wrote:As I look at the photo, there seems to be a curious 'streak' emanating from the portion of the moontrail at the point where the moon is entering the earth's umbra. It's towards the right hand side of the moontrail outside of the larger scattered annulus of moon light due to atmospheric effects. It seems to be narrow at what would be the moon's position, and fans out as it trails away from the moon. Is the phenomena the Gegenschein, Zodiacal light or the back scattering of dust and ions moving away coming off of the Moon itself, peeled off by Solar wind pressure in a kind of 'cometary tail'?
I'd say it's simply scatter off of thin clouds which we can't see in such a long exposure because of their movement. It is certainly none of the things you suggest.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by mproebstle » Sun Oct 11, 2015 12:38 pm

As I look at the photo, there seems to be a curious 'streak' emanating from the portion of the moontrail at the point where the moon is entering the earth's umbra. It's towards the right hand side of the moontrail outside of the larger scattered annulus of moon light due to atmospheric effects. It seems to be narrow at what would be the moon's position, and fans out as it trails away from the moon. Is the phenomena the Gegenschein, Zodiacal light or the back scattering of dust and ions moving away coming off of the Moon itself, peeled off by Solar wind pressure in a kind of 'cometary tail'?

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by volunteer » Fri Oct 09, 2015 6:29 pm

Anyone know what the streak coming from the tree at about the 10:00 position is? Maybe the ISS?

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Ron-Astro Pharmacist » Fri Oct 09, 2015 4:58 pm

This image is a nice reflection on shadows, distance and time. I like its composition and applaud the photographer's insight and imagination to capture light in varieties of intensities and dimensions. In black and white, its "color" is left to the eye of the beholder. :clap:

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by gregl » Fri Oct 09, 2015 4:37 pm

bjrolland wrote:I cracked up laughing at the writer calling a 4x5 Speed Graphic a "point and shoot" camera.

I suppose the news photographers of the time who used Speed Graphics could be thought of that way. They really did "point" them and "shoot". But there was a lot of experience and thought involved in the settings of the camera before it was "pointed". You couldn't just ramdomly aim it and hit the shutter like a modern point and shoot with a computer inside.

I used a Speed Graphic in my younger days but always on a tripod. Taking one picture could involve several minutes of setup time.

And then there's the Leica. It was (but wasn't really) the first point and shoot because, again, you had to involve your knowledge to prepare the camera before touching the shutter release.

Meanwhile, I enjoyed the posted picture.
I wonder if a similar thing could be done with a digital camera if you could figure out how to keep it powered on for an hour and a half.
Yup. I, too, shot many photos with a Speed Graphic. Not even close to a point-and-shoot. Here's the drill:

-Hold the 6 1/2-pound camera (the separate flash adds another pound or so) with your left hand while operating the controls with your right.
-With significant experience or a hand-held light meter, set the f/stop and shutter speed.
-Cock the shutter
-Focus manually using either the ground glass or the attached rangefinder
-Insert the 4x5 sheet film holder
-Pull the holder's dark slide
-Aim and compose shot
-Fire shutter
-Insert the film holder's dark slide
-Remove film holder, find a place to put it, and prepare for next photo.

Quite frankly, I don't miss it a bit. My 6-oz. point and shoot does just fine.

Keep those great photos coming. A bright spot in every day.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Boomer12k » Fri Oct 09, 2015 4:28 pm

bjrolland wrote:I cracked up laughing at the writer calling a 4x5 Speed Graphic a "point and shoot" camera.

I suppose the news photographers of the time who used Speed Graphics could be thought of that way. They really did "point" them and "shoot". But there was a lot of experience and thought involved in the settings of the camera before it was "pointed". You couldn't just ramdomly aim it and hit the shutter like a modern point and shoot with a computer inside.

I used a Speed Graphic in my younger days but always on a tripod. Taking one picture could involve several minutes of setup time.

And then there's the Leica. It was (but wasn't really) the first point and shoot because, again, you had to involve your knowledge to prepare the camera before touching the shutter release.

Meanwhile, I enjoyed the posted picture.
I wonder if a similar thing could be done with a digital camera if you could figure out how to keep it powered on for an hour and a half.
Noise Saturation not withstanding, you just need external power...

12v battery and small inverter, using the American or Euro Plug...depending on location....and you would have enough power to do it....also, my Samsung F40 has about 4-5 hours of run time....just no long exposure....sigh...10-20 Amp Hour battery could do it with a small 2-400 watt inverter....see my photo of my 100 amp hour set up with 400 watt inverter...this runs 20amp @12v weed whacker, 300 watt one cup coffee maker, anything up to around 30 amp @ 12volt. Will run my 10" Meade telescope and my laptop.
My 2 100 amp hour system seen left runs that microwave oven, with a 1500 watt Pure Sine Wave Inverter...no more cooking outside in a power outage at 18 degrees... Both systems are Solar Rechargeable. :shock:

ALSO....USB external battery around 10-16,000 MHA...if your camera can use USB, several of mine do. And while you wait...you can play on your tablet... :D

:---[===] *
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Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Nearly Ancient » Fri Oct 09, 2015 4:28 pm

My Brownie Hawkeye was point and shoot with a fixed focal length and shutter speed, although you could hold your finger on the trigger to hold the shutter open longer if you wanted to. And of course the flash bulbs could double as blasting caps.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Jarod997 » Fri Oct 09, 2015 3:18 pm

Perhaps I should have injected "an off-the-shelf". Nice shot Chris. :)

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Chris Peterson » Fri Oct 09, 2015 2:22 pm

bjrolland wrote: I wonder if a similar thing could be done with a digital camera if you could figure out how to keep it powered on for an hour and a half.
Yes, it would be as trivial as using film. You couldn't use a typical DSLR, since the noise would saturate the image in a 90-minute exposure. But almost any cooled astronomical camera is capable of making 90-minute exposures with low noise.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Chris Peterson » Fri Oct 09, 2015 2:19 pm

Jarod997 wrote:You can't do THAT with digital. ;)
Of course you can.
eclseq2.jpg

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Jarod997 » Fri Oct 09, 2015 1:29 pm

bjrolland wrote:I cracked up laughing at the writer calling a 4x5 Speed Graphic a "point and shoot" camera.

I suppose the news photographers of the time who used Speed Graphics could be thought of that way. They really did "point" them and "shoot". But there was a lot of experience and thought involved in the settings of the camera before it was "pointed". You couldn't just ramdomly aim it and hit the shutter like a modern point and shoot with a computer inside.

I used a Speed Graphic in my younger days but always on a tripod. Taking one picture could involve several minutes of setup time.

And then there's the Leica. It was (but wasn't really) the first point and shoot because, again, you had to involve your knowledge to prepare the camera before touching the shutter release.

Meanwhile, I enjoyed the posted picture.
I wonder if a similar thing could be done with a digital camera if you could figure out how to keep it powered on for an hour and a half.
Ya, I chuckled at that point too - the point-and-shoot part. I used to help my dad shoot weddings with a Hassleblad, and while that is much more of a point-and-shoot camera than the Speed Graphic, it was still very much a manual camera and you had to load the film cartridge in the dark.

You can't really take a long exposure image with digital because noise starts to creep into your image - it's not a power limitation. There are some manufacturers that do a clever job at noise reduction, but you'll never do a good job at taking a long exposure dark image on digital. Ok, ok, for the digital enthusiasts, you could take a large number of shorter, better quality night images and composite them later - but that's a lot more work.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by bjrolland » Fri Oct 09, 2015 1:16 pm

I cracked up laughing at the writer calling a 4x5 Speed Graphic a "point and shoot" camera.

I suppose the news photographers of the time who used Speed Graphics could be thought of that way. They really did "point" them and "shoot". But there was a lot of experience and thought involved in the settings of the camera before it was "pointed". You couldn't just ramdomly aim it and hit the shutter like a modern point and shoot with a computer inside.

I used a Speed Graphic in my younger days but always on a tripod. Taking one picture could involve several minutes of setup time.

And then there's the Leica. It was (but wasn't really) the first point and shoot because, again, you had to involve your knowledge to prepare the camera before touching the shutter release.

Meanwhile, I enjoyed the posted picture.
I wonder if a similar thing could be done with a digital camera if you could figure out how to keep it powered on for an hour and a half.

Re: APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by Jarod997 » Fri Oct 09, 2015 12:52 pm

You can't do THAT with digital. ;)

APOD: The Moon Entering Earth's Shadow (2015 Oct 09)

by APOD Robot » Fri Oct 09, 2015 4:06 am

Image The Moon Entering Earth's Shadow

Explanation: On September 27/28, from all over the planet's nightside moon watchers enjoyed a total lunar eclipse. The dramatic celestial spectacle was widely imaged, but this lunar eclipse picture may look a little strange and unfamiliar, made with a point and shoot camera of a bygone era. Loaded with a 4x5 inch sheet of film, the Speed Graphic camera was fixed to a tripod on the Island of Cyprus. Its shutter locked open for 90 minutes, it recorded the trail of the Full Moon at perigee from the beginning of the partial eclipse phase (top) until mid-totality found the Moon near the western horizon. Entering Earth's shadow, the Moon grew dimmer and its moontrail narrower as the eclipse progressed.

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