Inspired by Jim

I dug out an old (2007) picture of a full lunar eclipse. This was shot at iso3200 and about 2 seconds iirc, using an 1800mm Maksutov cassegrain mirror scope and my 5D. I've actually got a series as it went into eclipse - moving the iso rapidly - and probably ought to revisit some as the noise reductoin capability of raw software has improved somewhat since then.

The colour is genuine, albeit with a little bit of extra saturation arising from increased contrast.

And Jim's right, the moon moves out of frame pretty quickly at these focal lengths. I'm fortunate in that my scope tripod has a sidereal motor drive, which can keep it pretty still for 2 to 3 second exposures.

Mike

Mike Shimwell said:

I dug out an old (2007) picture of a full lunar eclipse. This was shot at iso3200 and about 2 seconds iirc, using an 1800mm Maksutov cassegrain mirror scope and my 5D. I've actually got a series as it went into eclipse - moving the iso rapidly - and probably ought to revisit some as the noise reductoin capability of raw software has improved somewhat since then.

The colour is genuine, albeit with a little bit of extra saturation arising from increased contrast.

And Jim's right, the moon moves out of frame pretty quickly at these focal lengths. I'm fortunate in that my scope tripod has a sidereal motor drive, which can keep it pretty still for 2 to 3 second exposures.

Mike

2007 Lunar Eclipse - Mike Shimwell

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I love the color! Is that from the atmosphere where you are and would it be different elsewhere as the angle of the moon changes and the depth of the earths atmosphere, (from that angle), changes?

Do you have a picture of you setup and is the speed of the side rail constant or do you change it according to the angle of the moon in the sky. If I'm correct, the speed would change as observed on the earth.

Also, what's that star? Is there now enough information n the picture for someone to calculate where you are located, knowing the date of the picture?

Asher



Asher

Hi, Asher,

Asher Kelman said:

Do you have a picture of you setup and is the speed of the side rail constant or do you change it according to the angle of the moon in the sky. If I'm correct, the speed would change as observed on the earth.

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I believe that, from a geometric standpoint, sidereal tracking would work the same regardless of the position of the moon in terms of elevation at any point on the earth. But is is only an approximation as the moon's "sidereal position" (an imprecise term) changes with time.

A sidereal mount (at least in "classical" operation) keeps the instrument "aimed at the same point in distant space" as the earth rotates and revolves.

Asher Kelman said:

I love the color! Is that from the atmosphere where you are and would it be different elsewhere as the angle of the moon changes and the depth of the earths atmosphere, (from that angle), changes?

Do you have a picture of you setup and is the speed of the side rail constant or do you change it according to the angle of the moon in the sky. If I'm correct, the speed would change as observed on the earth.

Also, what's that star? Is there now enough information n the picture for someone to calculate where you are located, knowing the date of the picture?

Asher



Asher

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Hi Asher, the colour is the result of the light that strikes the moon during the eclipse has been filtered (and refracted) through the earth's atmosphere. The moon is in the earth's shadow and so the only sunlight that reaches t is the small amount that bends through the atmosphere. Because the path is long there is a lot of blue scattering and it's like a very deep sunset and very dim. The colour wouldn't vary provided your in the areas where the eclipse is total - before the eclipse the moon is lit by direct sunlight and is white, then as the earth's shadow crosses the face of the moon the darker area is seen to be red.

As Doug, unsurprisingly correctly, points out, the sidereal drive is designed to allow the scope to stay true on deep space objects and doesn't work well for the moon. But, it's a lot better than a stationery tripod - the moon moves surprisingly quickly when viewed through an 1800mm lens.

I don't know what the star is, but I've never seen it when the moon is not fully eclipsed as it gets lost against the moon's glare.

Mike

Hi Mike,

This is a striking image of the good old moon and you did a great job of capturing it so sharply. Amazing!

Cheers,

Honored Mike. Wish mine was half as nice. Actually the old Zoomar had been languishing in a cupboard for the past 30+ years and my young boss wanted to see what it could do. I wandered into the machine shop and made a suitable mount for the Nikon.

Mostly it fails. Mushy images, poor contrast and frightening color rendition. We can't think of anything it's good for.

Yes, we did go out at prime PM and we shot it against a 1000mm CineTel. So, out they go. There were 3 of them. Zoomar! I would guess 1969 - 1973 and be close.