Re: RCX400 Collimation Restore to Defaults- how long does it take?
- The final results aren't in yet, but - it looks like my elongated stars may have been caused by a problem with the MX's "ProTracking" software function somehow making the mount's tracking worse instead of better.
I took some images tonight, up to 10 min in duration, and the elongation appears to be gone. But I'll look at the images tomorrow in the light of day, and then figure out what I've got.
Who'd a thought that a Paramount's professional tracking software would cause this kind of weird problem? Thanks for the tip, Andy !!
--- In RCX400@yahoogroups.com, "Rod" <rodsrun@...> wrote:
> Well, despite my determination to make this into a more complex problem than it might be, I see the overwhelming majority opinion is simple tracking error. I can live with that conclusion... its a lot easier to fix than primary mirror astigmatism, that's for sure. :) And since I've confirmed colliimation isn't the problem, tracking makes the most sense.
> I'm a little concerned though - I followed the Paramount's MX polar alignment procedures until the software reported that my DEC and RA mount adjustments were correct. Then I did a 200+ point T-point model, from which the MX software extracted information to configure its ProTracking function. While imaging, the MX mount reported via TheSkyX Pro software that it was "tracking at sidereal rate". What you see in the image I posted is the result of all that... the image was taken with ProTrack running (without the AO-8 in operation).
> To complete the setup picture I have, in answer to other's ideas and suggestions:
> - the 7"x7" pressure-treated wooden pier has been in the ground since May08, sunk down six feet (well below the frost line) and anchored in cement
> - a pair of aluminum levelling plates sit atop the pier, and provide the platform to which is attached the MX base
> - the OTA is rigidly held in an Andy Homeyer cradle mounted to the MX versa-plate at six points (3 per side) by nuts and bolts
> - the OTA is balanced in both DEC and RA so that you can release the drive clutches, spin the OTA anywhere, take your hands off it - and it stays exactly where you put it
> - all cables are kept short between the MX Versa-plate connections and the camera assy, and have been confirmed not to catch on anything throughout the entire range of OTA motion, pier-side to pier-side
> - the whole scope setup is housed in a SkyShed POD, sitting on a wooden deck, with the deck and POD structures physically isolated from the pier
> - power to the MX is via its OEM power supply, power to the camera assy is via SBIGs OEM power supply, power to the Feather Touch focuser is via the OEM power supply
> - 120VAC power is provided to the POD contents via dedicated circuit in conduit from house to POD, and is distributed to the POD consumers through high-quality surge protected power bars
> - USB communications from the scope components in the POD to control-computer are via a USB-IP hub mounted at the scope and connected to the house ethernet network
> So - I think what I'll do, rather than try to find a single point of error in what I have now, is just start over: zorch the T-point model and turn off ProTrack; check that all bolts are tight, all cables tied down, that the camera assy is tightly coupled and immoveable; redo the MX Polar Alignment procedure; do another 200+ target T-Point model; redo the PEC training; and then try ProTracking again.
> Thanks for your input, everyone. It wasn't what I expected, considering the MX's reputation for tracking after following its OEM setup process, but hey - the images don't lie: something isn't right, so starting over is probably the best way to resolve the problem.