Some quick shots of the Moon with the 20" scope

Hi All,
Given we had a good moon in the sky, I turned the 20" obsession on it over the week and got a few shots.
I found that I cannot reach focus with the Canon using "prime focus" or "eyepiece projection", so I have to use "afocal" where I use the cameras lens and the scopes eyepiece. I know I can cut the truss poles, but am not going down that road for now. Focusing was done by eye, through the cameras finder. I used the Canons standard lens and a 31mm T5 nagler eyepeice.

This one is of the southern polar region, its a single frame (no registax) from the camera, with levels adjusted in photoshop.
www.flickr.com/photos/61288385@N00/55409...es/o/in/photostream/

This is slightly further up north
www.flickr.com/photos/61288385@N00/55409...es/o/in/photostream/

Shows several seas on the Moon including the Appenine mountains, again a single frame
www.flickr.com/photos/61288385@N00/55409...es/o/in/photostream/

Shows Tycho during an almost full Moon, note the splatter rays to the top and left. This came out alot better then I thought it would and are far more obvious then they would be through thr 12" scope I have. Note the irregular terminator showing the mountains on the edge of the moons limb.
www.flickr.com/photos/61288385@N00/5540936394/

First quarter, slight vignetting is due to me not having the camera centered over the eyepiece.
www.flickr.com/photos/61288385@N00/5540906752/

This one shows the western edge of the ocean of storms, including Schroters Valley, Aristarchus and Kepler, 12 images were stacked for this shot.
www.flickr.com/photos/61288385@N00/55402...es/o/in/photostream/

A more close in view of Aristarchus, visually through the eyepicee, you could clearly see the steps in Aristarchus's crater with a peak in the center,
www.flickr.com/photos/61288385@N00/55402...es/o/in/photostream/

Next time, I hope to get enough good images to stack them in registax,focusing was very easy as you can imagine the moon is extremely bright through the scope/camera combination. Also, the view through the eyepiece is far sharper then any image here, but the seeing that night was not the best.

Great shots none the less Dave.
Can you not get an extension tube to help with the focus using the camera?
Very good work...

Thanks, The focusing problem is in the other direction, I'd need to bring the camera closer to the primary mirror, not further, so maybe a smaller profile focuser to get the camera more in there or reduce the truss pole lengths, but this can have the problem of effectively reducing the aperture of the scope.
but to be honest, I'm happy using the afocal method of using the eyepiece and the zoom lens of the camera to up the magnification, it surprisingly works very well with no obvious optical abberations thankfully except for vignetting when I dont get the eyepeice centered, but thats my fault, not the systems.

Nice collection Dave. Very sharp and lot's detail well done.

Hi Dave,

Very nice photos, the power of the 20" is apparent.

As regards the problem with using the Canon at prime focus, one possibility, albeit probably not a very practical one, is to try a DSLR with a shorter flange back distance. I use a micro four thirds camera which has a much shorter distance between the flange and the sensor, so it might be possible to get a camera of that type to focus. If you have tons of money get yourself a Panasonic GH2, a snip at approx €1000, , or if you plan to bring the 20" at any IAS/SDAS get-togethers, you might like to try my GH1.

Cheers, Mike

Fine images Dave.

I would suggest a DMK and process the clips in Avistack2.
You won't have the same FOV of course, but the images would be savage with the resolution of the 20".
Avistack2 is free and is slightly better than Registax.

Michael.