William Optics 132 refractor
The latest equipment acquisition is a second hand William Optics 132 refractor.
This is it on the old EQ6 with binoviewer.
Before I purchased it I did a few tests. There was only one clear night available.
William Optics 132 testsA Canon 350D was used for the tests.
Aerial about 300 yards distant. Stack of best 14 out of 30.
St Johns church. 2000 feet distant. Best 20 from 50 images in fading light.
Arcturus out of focus. Nice round rings showing optics are not pinched in the cell.
13 second exposure of Arcturus. The image shows a much enlarged copy of some stars at the end of each arrow.
Stars away from the centre are elongated, showing that a field flattener is needed for astrophotography.
Stack of best 8 images of Deneb. 30 seconds exposures with no guiding and very rough and ready polar alignment.
Need for field flattener quite obvious at the corners.
Negative of above image
Stretched to show degree of vignetting. The camera was a Canon 350D with a 1 1/4" adapter which probably contributed most of the vignetting.
Bahtinov image on Deneb
I liked what I saw and made the purchase. A Moonlite focuser was included, seen here on the ASA DDM60 mount.
Considerable back focus was needed. An extension tube was purchased. The Moonlite is almost at full extension.
July 11th 2012
First light - M13
There was only a brief spell of clear sky, sufficient for a single 10 minute exposure through the Luminance filter.
Weeks of cloudy skies followed. For the next images, see July 2012
Update - June 22nd 2013
The William Optics scope is now sold. My homemade 10" Newtonian is back on the mount.
I like the extra light-grasp it has over the refractor, and is likely to remain my main scope for some time.
I also have the AE Luton refractor that I am renovating, and it seems daft to have three scopes.
The reflector is such a massive beast that I cannot change scopes on the mount without help,
so swapping scopes every few days is not an option.