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Howdy! I took today's shots late last night, when Saturn was directly overhead and the Moon was a bit to its right. My goal was to photograph Saturn, but that didn't work out very well:

This shot does show that the rings are pretty much edge-on right now, and that's interesting, but the camera just doesn't know what to do with really bright objects. To the naked eye, I could differentiate the ring from the planet - like a very slight shadow on the globe below - and what appeared to be four of its moons. Titan was obvious and I thought for sure it would show up in the image, but its parent planet was so bright that it overwhelmed the light from its little coterie of worlds. I'll continue to play with this.

Oh, and I should mention: WINDY! Most shots were blurry due to wind. I really want an observatory ;-)

To take successful shots of the Moon, I used a masking technique to reduce the amount of light entering the telescope. My high-tech method included standing beside the tube and slowly moving my arm in front of the aperture to block up to about half the light. This took advantage of the 'scope's full resolution power (full width of the mirror) without its full light-gathering power. Shots I took without masking showed bright areas as washed-out and pixelated. The best shots seemed to be when I blocked most of the light by placing my arm (in a thick jacket) across the widest part of the aperture. Oh, and I was also using a polarizing filter set at its darkest (about 40%). This should give you a little idea of just how damned bright is the Moon through a 12" telescope. It's also a bit too long-focus to take full shots of the Moon: Note that only a small portion of the world shows up in each shot. That's without any magnification (no eyepiece), directly into the camera, and with the focal length shortened by 37% from using an f/6.3 focal reducer. Okay, the shots:

In this first photo, notice the two bright craters with what looks like stripes spreading out from them. Those are called rays, detritus from the impacts that created those craters. Also notice that some craters are dark and some are light; this has to do with what was going on geologically on the Moon at the time those craters formed. Really dark ones show melted rock that filled the craters from deep below, and bright ones are filled with Lunar dust. Even more dramatic are the vast maria, the huge dark areas rimmed by brighter walls. Yes, those are the remnants of massive craters that almost destroyed the world back in its earliest days.

This next one is all about showing off the rayed crater, Tycho. Imagine the energies involved in creating rays that span nearly half the globe!

Finally, this last shot is from the first set I took, which I like in that it shows the unlit edge of the world (nearly Full Moon during the photo-shoot) plus lots of contrasting-brightness craters and maria:

If you want to identify all the craters, I found a good map here:

Click the image to see the site.



( 15 comments — Leave a comment )
Feb. 10th, 2009 07:52 pm (UTC)
Oh, man! Those are your photos of the moon??? Woweeeeee! Those look fantastic! Congratulations! I'm so happy for you!
Feb. 10th, 2009 08:04 pm (UTC)
Thank you! They're much blurrier than I'd like due to wind, but still pretty nice.
Feb. 10th, 2009 08:39 pm (UTC)
Great pictures! I love the Moon. I can never get tired of the Moon in SF, no matter how many times it's used as a setting or part of the plot.
Feb. 11th, 2009 07:45 am (UTC)
Thanks! Yeah, I know; as often as the Moon is out, I turn my telescope to it. It's a world so close that we can inspect features as small as buildings with a backyard telescope! I think because of that, the Moon comes alive in fiction, too.
Feb. 11th, 2009 05:00 am (UTC)
These are so awesome, thank you for sharing and enlightening us!
Feb. 11th, 2009 07:46 am (UTC)
Glad you like 'em! Some time when you have your kids and it's clear and the Moon is up, I'll be happy to give them the tour.
Feb. 11th, 2009 05:23 am (UTC)

Okay, if Saturn was directly overhead at night, then what I saw was definitely not Saturn. I just hope I really was looking at the ISS and not just a plain ole satellite! :)
Feb. 11th, 2009 07:50 am (UTC)
The planets don't really move across the sky any faster than the stars (to the naked eye, anyway), so what you saw was almost certainly a satellite of some type... and you should be able to look up where the ISS is at any point and look for it!
Feb. 12th, 2009 09:12 pm (UTC)
these are so kewl!!!
i understand what you're saying about the saturn image, but it is still really amazing that you could get a picture of something so very far away!!! and i think the thing looks super cute!

to me, it makes perfect sense that you had to block the light, but i do love your high-tech way of doing it!

i hope you get your observatory one day!
Feb. 12th, 2009 09:42 pm (UTC)

Even it it's a long time before I get an observatory, I still need to get something to block ambient light and wind. Just a little porta-wall thing would be so helpful.
Feb. 13th, 2009 02:15 am (UTC)

Nice pictures. Sometimes it's tough fitting larger objects into the field of view of a larger telescope. I've had good results with my eight-inch too; we don't have Kansas winds here, which also makes things easier.

Planets are a lot harder. I've never come close to that good a shot of Saturn. Even with Jupiter, I barely managed satellite shadows and bands, and never both at once. I haven't been able to find my eyepiece projection accessory in a while, so I'm not likely to do any planets any time soon.

What kind of camera did you use?

Feb. 13th, 2009 08:50 am (UTC)
Yeah, I really need to build myself a wind guard, vinyl and PVC at least.

I use the Meade DSI-III for taking shots; the telescope is also a Meade, LX90GPS 12".
Feb. 13th, 2009 11:01 pm (UTC)
That sounds cool. I'd use a digital SLR right now. I'd like to try it out on the Sun some time too, but it's tough taking pictures through a hydrogen alpha filter.
Feb. 20th, 2009 06:23 pm (UTC)
These are wonderful! Apparently there is a comet out at 4am tonight- are you going to try to get pics of it?
Feb. 20th, 2009 06:37 pm (UTC)
Yes! Thought not tonight. I've been meaning to catch that as soon as the Moon is out of that part of the sky. And when it isn't forecast to be cloudy :-(
( 15 comments — Leave a comment )

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