We get this question many times, "will the
Mach2 support my scope, camera etc." I can't really answer
specific setups since I don't have infinite variety of
scopes at my disposal. However, to give you some idea I am
presently testing two scopes piggybacked on the Mach2.
Here is my present setup. I am using it to
test various optics, cameras and field flatteners. It
consists of a 160EDF refractor with QTCC and a full frame
ZWO 6200 color camera, which provides a very wide field. On
top rides an oldie but excellent 130 EDF refractor with 2.7"
focuser, 67PF562 Flattener and my QSI 683WSG camera,
Lodestar off-axis guider and an 8x50 Baader finder for good
measure. Both scopes sit in rings that are attached to
dovetail plates. When you add up all the parts, the whole
shebang weighs close to 70 lb with the weight centered about
9 inches from the top of the Dec axis. I have approximately
75lb worth of counterweight which includes the weight of the
standard Mach2 cwt bar and the shorter extension.
Is it stable and does it slew, track and
guide effortlessly? Yes on all counts. It does need to be
closely balanced, but not ridiculously so. Using MaximDL6,
in poor seeing i get on the order of 0.4 arc sec rms
guiding. In good to excellent seeing I get 0.1 to 0.15 arc
sec rms guiding. My guide exposure is between 2 and 5
seconds with 1.5 seconds between exposures. Best guiding
seems to be when the exposures are 4 to 5 seconds, and I get
very few excursions that are larger than 0.5 arc sec pk.
By the way, I don't usually guide with one
scope and image with another. In this case I am guiding with
the lighter weight 130EDF and I am getting perfect round
stars with the 160 below. The 160 is shooting at 960mm focal
length with a 3.75 micron/pixel camera, 0.8 arc sec per
pixel. ZWO 6200 camera. resolution with this camera in
medium seeing has yielded 1.4 arc sec FWHM stars in a 5
I will be shooting tonight if the weather
holds, and I can record some guide graphs for anyone
interested. Seeing is supposed to be good (4 out of 5) but
transparency will be poor. I'm doing a shootout between the
CMOS camera with 3.75 micron pixels and my older QSI683 CCD
camera with 5.4 micron pixels. Which camera records images
faster? Which has better contrast? Any bets on the winner?