Search the Community
Showing results for tags 'az-eq6 gt'.
Found 3 results
Hello everybody, I am going to apply Permanent PEC correction to my AZ-EQ6 GT SkyWatcher mount in an attempt to eliminate most minor negative contributions to my so-and-so autoguide. I will do that by following instructions on the SynScan manual. Does anyone have some advice? I also started using Guide Assistant of PHD2 and applying the calculated min-move and backlash changes suggested by the system. More, I tweaked the worm and gear bugs of the DEC axis to reduce the backlash, and after a few attempts I found the right position between screeching and jerky movements of the mount at one extreme, and shaky setup at the other. I hope getting some improvements to my awkward setup because I am afraid that the heavy (14-16 kg) and long (1600 mm focal length) Meade 7" refracting scope plus guide scope is close to this mount's limiting payload, and difficult to be correctly balanced. In addition to seeing, its length also makes it strongly sensitive to wind gusts making PHD2 log graphs look not so good. I cannot minimize these effects without changing my scope, which I don't want to do because of crisp images it yields under (rare) favourable conditions, so I started a search to minimize everything else that can be addressed. Thank you for useful suggestions!
Hi all first post here! I've been reading your forum's post for a long time and I have found really instructive and educational information. Last year, I bought my first telescope to fulfil my dream! A combination of a Skywatcher Black Diamond 120ED and an AQ-EZ6 GT mount. Last year I tried the visual part, to learn the basics and take some photographs (with mediocre results). This year I tried to improve my photographic skills. The first thing I noticed was that I could not take a photo without extreme star trailing. As I've read, a bad polar alignment would be the cause. So I tried carefully to improve it through the PA scope of the mount, or with the 3-star alignment of the mount with no good results. The strange thing I noticed looking through the eyepiece, was that sometimes the stars were drifting, after I had released the keypad button during the alignment. Last month I bought a QHY5L-II camera to use it as a guiding camera. I connected the mount to my laptop using a custom made adapter (cost me 14€) and with the very good EQMOD drivers, I start using software solutions for Polar Alignment, including PHD2 and EQAlign (more accurate and friendly but a little bit buggy). For guiding I tried also the MetaGuide (the only one that allowed me to take a photo of 30 secs!! without trailing). I soon realized that the mount should have significant Periodic Error on the RA axis. Using PHD2 and these instructions http://eq-mod.sourceforge.net/docs/eqmod_vs-pec.pdf (appendix A), I measured the PE curve of the mount and imported the measurements into the PECPrep for evaluation. The peak to peak value is extreme: 130arcsecs Strange thing is that the period of the PE is not the period of the worm but a quarter of it: It is worm's fourth harmonic or Stepper motor's period (119.67 secs). A harmonic cannot have larger amplitude than the base frequency, so I guess something is wrong with the stepper motor or the motor pulley or the motor driver circuitry or maybe the belt. I changed the belt with a new one (a Contitech Syncroflex) and repeated the measurement but the results where similar. The contribution of the 116.67secs error is 3 to 4 times more than the error from the worm. The resulting PE is really difficult to be handled by the PHD which after 5 to 10 secs fails to follow the movement. Even at the calibration phase it prompt errors regarding the orthogonality error. Drift align is almost impossible with PHD (target circle never gets steady but keeps growing and then shrinking and back again). Any suggestions? Thanks in advance, Panayiotis