Astrometric Instruments' Photo Gallery
This gallery contains images sent in by users of SkyWalker1 and SkyWalker2.
The first three images below were taken by Leonard L. Amburgey at Scott Observatory in Fitchburg, MA. His equipment consists of a Takahashi CN212 with an SBIG ST-7E camera mounted at the 820mm FL, F/3.9 Newtonian focus. This combination results in an image scale of 2.25 arcseconds/pixel (the images shown here have been cropped from the originals). The mount used was a Losmandy G-11 with a SkyWalker2 RetroKit installed in place of the original Losmandy Model 492 Digital Drive System.
These images demonstrate the tracking accuracy of SkyWalker as all three images were UNGUIDED for periods ranging from 8 to 10 minutes. The only correction applied was SkyWalker's Programmable Mechanical Error Correction (PMEC) feature (includes correction for periodic error).Close inspection of these images (>4x) will revel that all of the stars are symmetrical. Many of the dim stars appear as squares 2 pixels on a side, with some of the dimmer stars fitting into a smaller area. These images demonstrate no more then 2.25 arcseconds of error over the 8 minute exposure. Leonard tells us he can do better and get a 15 minute exposure with similar results after tweaking the polar alignment. Good luck Len, let us know when the images are available.
NGC205
8 minute exposure
13 arcminutes x 12.5 arcminutes
NCG206
8 minute exposure
13.6 arcminutes x 15.4 arcminutes
NGC891
10 minute exposure
13.3 arcminutes x 14.7 arcminutes
The next three images below were taken by Brian Lula of Princeton, MA. The scope is a home built 20" f/4 Newtonian with a custom built Coastal Optics 75mm clear aperture field corrector providing 1.25x magnification (resulting in a 100" FL F/5 optical system with an image scale of 1.95 arcseconds/pixel) and 6" minor axis secondary for 100% illumination of the CCD. The camera is a Finger Lakes IMG1001E (KAF1001E CCD Array). As with the telescope, Brian designed and fabricated the mount. The control system is SkyWalker1 with a Klinger MD4 motor driver. An autoguider was used for these three images.
Brian originally sent the nearly
raw images (only calibrated with dark and flat frames and
removed the hot and dark pixels) but the 2+Mbyte .FIT files would
too much for most connections to the Internet. Below are .jpg images
which loose a little in the translation...
Flame Nebula
composite of fourteen 30 second exposures
33 arcminutes x 33 arcminutes
(click on image for full sized version)
IC5067
composite of fourteen 30 second exposures
33 arcminutes x 33 arcminutes
(click on image for full sized version)
Merope Nebula
composite of fourteen 30 second exposures
33 arcminutes x 33 arcminutes
(click on image for full sized version)
Any copying, storing or distribution
of these images is expressly prohibited without the written permission
of the copyright holders.
