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View Full Version : Lunar Eclipse, February 20, 2008



Noel Carboni
02-24-2008, 07:34 PM
A combo of two images, the first showing the point where the Earth's full shadow (umbra) was starting across the moon, and the second in total eclipse and illuminated only by light refracted around the Earth's atmosphere. Each image was in turn stitched from multiple overlapping images taken at 2500mm f/10 with my Canon EOS-40D at prime focus of my Meade 10" LX200 GPS UHTC telescope.

Exposures were 1/125 second at ISO 100 and 1 second at ISO 1600. Images processed for maximum detail contrast and as much of a 3D look as I can achieve. In so many cases the moon looks like a flat disk, and I wanted these images to portray it as the sphere it is. Please let me know if you think I succeeded.

You may see a higher resolution image here: http://forum.ourdarkskies.com/gallery_images/1203564883/gallery_131_7_93893.jpg

-Noel

Arthur Morris
02-24-2008, 08:46 PM
Succeeded. Especially with the red one. Might look even nicer wider with a bit larger black borders on the side. Thanks for sharing. I am confused by your technique and the exposure settings...

later and love, artie

David Kennedy
02-24-2008, 09:36 PM
That is cool, and I think Artie's onto something re: extending the border. The moon certainly comes through with a lot of detail and pops out with the very three-dimensional feel that you describe. Also like Artie, I am a bit confused about how you put the multiple exposures together.

Howard Burkert
02-24-2008, 09:59 PM
Noel, Awesome detail in your images. Was wondering how you had your camera supported or locked down with 2500mm.and what part of the country they were taken from? They are among the best I have ever seen!!
Best,
Howard
As an after thought, I vision, the "Total Moon", printed alone, square with a copper fillet, black velvet mat and copper tone frame. I think you have a real work of art in this one.

Noel Carboni
02-25-2008, 06:28 AM
Thanks everyone!

Here's a bit more detail on what was involved:

1. I have a 10" Meade LX200 GPS UHTC Schmidt-Cassegrain telescope, which besides providing a very long focal length in a compact package, has motors for tracking celestial objects. This is important for lunar eclipse photography, as the exposure times can get fairly long when the sunlight has been blocked by the Earth from reaching the moon. Oh, and the setup has its own big field tripod. It's all very heavy and stable when set up.

2. I have added a T-mount with appropriate camera adapter. One end slips into the 2" tube in the electric focuser on the telescope and secures with the thumb screws, and the other mounts to the Canon camera body like a lens. There are no electrical connections in this device.

3. Once I aligned the telescope, a process whereby it figures out (via GPS) where it is on the Earth and what direction it's facing (via a magnetic North sensor) then finally asks me to center two stars, I punched in "Solar System", "Moon", and "GOTO". The mount pointed at the moon and began to track it (not only compensating for the rotation of the Earth, but also including the rotation of the Moon around the Earth). This thing is way cool.

4. With the camera on the scope, and with the eclipse *just* starting, I enabled Live View, got the focus close and locked the mirror down in the scope. Looking at the edge of the moon at 10x in Live View, I fine tuned the focus using the scope's electric microfocuser. I set the camera to ISO 100 and 1/100 second, and took some test JPEGs. I could see some movement in the features of the moon due to atmospheric effects - heat waves. This is typical at this magnification.

5. I switched to Raw mode, and began taking sequences of shots to cover the entire moon every so often to capture the progressing stages of the eclipse. I could probably have done it with as little as 4 shots each, but I took more because I wanted to make sure to have enough overlap to get good mosaics. I used the fine positioning control on the telescope's handset to reframe the image, and my TC80-N3 remote timer controller to trigger the exposures, so as not to jiggle the scope. No matter how solid, movement is still a problem at this high focal length. The difference in brightness between the bright sunlit portion and the part falling in the umbra (full shadow) of the Earth is huge, so I switched to a higher ISO and a longer shutter time to bring out shadow detail.

6. When the eclipse reached totality, I found that I was shooting in ISO 1600 for a full second, which is something like 12 stops slower than I had been shooting when the moon was entirely in the sun.

7. Creating a full mosaic of the fully illuminated or fully eclipsed moon (i.e., with all the same exposure times for every image in the mosaic) is as easy as running the Photoshop CS3 Photomerge function. Fortunately the telescope presents a reasonably flat field to the imager, so stitching is essentially a matter of alignment, without need for distortion.

8. At full camera resolution the resultant moon mosaic image comes out to about 30 megapixels, but when the seeing is blurring the features on the moon like it was the other night it's not necessary to use such a high resolution. Looking over the raw data, I chose to use one of the lower resolutions offered by Camera Raw and still got a highly detailed high megapixel resultant image.

I can only imagine how spectacular the Earth looks from the moon during one of these events.

-Noel<!-- google_ad_section_end -->

Robert Amoruso
02-25-2008, 07:00 AM
Thanks for the detailed description Noel. I too would like to see a larger black border for the images. I would agree that they do have a 3D look to them.

Howard Burkert
02-25-2008, 06:25 PM
Noel, Thanks for the details on your images. You have really mastered your equipment, and it sounds very complex. Yes the sight from the moon, looking at Mother Earth would top anything! It will be possible someday in the future. After all we are sending images from a computor and not long ago that was a dream..Again the images are outstanding!!
Best,
Howard

Judd Patterson
02-26-2008, 10:42 PM
Noel is certainly a true master of images like this. He has taken (and shared) some simply stunning moon photographs...makes me yearn for a tracking mount every time I see his wonderful work. Great job and thanks for sharing! Guess I should have driven north for this eclipse, as I saw nothing here...just clouds.