Hi all,
Having been an amateur terrestrial photographer for a while now I recently caught the astronomy bug and purchased a DSE 114mm Newtonian Reflector just to try (on special for $148, so who could complain). Whilst the OTA optical quality seems OK, the EQ mount it comes with certainly isn't. Tightening the tripod leg bolts beyond what I would consider normal removed a lot of the basic wobble, but there's a lot of play in the RA/Dec axes as well. Trying even lunar photography with a Konica Minolta Z5 looking down the eyepiece was a let down. Setting the 10 second timer and pressing the shutter button, the scope was still shaking significantly when it went off - a sign of really poor damping. (This was a clam windless night, too.) And no option of remote shutter release on the KM.
So I went out looking for better quality EQ mounts, with goto, but on a budget. I had a tough choice between a Celstron Advanced Series GT and the Meade LXD75 with an Autostar 497 controller. Both units were virtually the same price and both looked mechanically sound - each dealer decried the other's hardware as insubstantial, but they looked and felt the same to me. I finally chose the Meade because I knew for certain that I could get software to work with it (using ASCOM drivers or directly with LX200 protocol) and it came with a polar alignment scope built-in whereas the ASGT only had provision for one.
Now comes the fun.
Certainly a huge improvement on stability. I'm finally getting some half-decent shots (of bright objects, anyways, the KM doesn't have good low-light capability and a maximum 4-second shutter speed).
But the goto capability leaves a bit to be desired. I've tried using "easy", "two star" and "three star" aligns. Whilst it gets bang-on-the-money when you ask for one of the stars you aligned with, it's often 3-4 degrees out on other objects (according to the Telrad). I couldn't make it find M7 the other night no matter how hard I tried.
I'm told it's all due to polar alignment, especially since I've glued N-S and E-W bubbles on the tripod base to ensure it's level. The latitude scale is essentially unusable (why must the indicator arrow be so far away from the scale I wonder?) but I've set it fairly closely to my latitude using a bubble level on an adjustable square. Being within 10km of the city lights, though, I'm having real trouble finding Chi- Sig- Tau- and Ups-Octantis to make real use of the polar align scope and its etched overlays.
Can anyone provide me with suggestions for southern polar aligning the Meade, or even other methods of alignment? Most of the material out there spends reams on finding NCP using Polaris, but barely a line or two on finding SCP with Octantis.
[Next task: fighting-off the aperture bug - I'm eyeing-off a Guan Sheng GS-980 12" Dobs.]