Best guiding i've seen so far

[pyrasanth]

My seeing is usually pretty rubbish. I'm lucky to get under 2 arc sec on an average night. I measure guiding performance based on how good I can guide on an average night & not the rare perfect night when guiding is always going to be good bar equipment failure.

I have changed over the RASA back to the Celestron C11 Edge for the summer season as I want to capture some smaller objects. However I found that no matter how hard I tried I could not get a satisfactory guiding result beyond 4 minutes. Not with a good calibration with PHD, SkyX direct guide & even a manual guide scope. I was always presented with unhappy stars despite having excellent polar alignment and a superb mount. I started to wonder about inherent faults in the schmidt cassegrain design like mirror flop.

I looked for a solution where the mirror could be locked & focus was to happen by an alternative means other than moving the primary mirror. The back focus on the C11 is limited so an after market focuser was pushing the limits with the equipment I wanted to hang off the back. I was scanning the equipment sites as you do & I came across a company called Optec- very well known for there high quality telescope equipment. They developed a solution to the dilemma I faced and offer a system that focuses with the secondary mirror thus allowing you to lock the primary. I have tested this system for a week in conjunction with the ONAG that I purchased earlier from innovations foresight. Using the Optec fast Focus software that refocuses in real time as well as direct guide I now get the best guiding I have ever seen.

The ONAG guides in the NIR spectrum which is much less perturbed by seeing conditions as viewed through white light- your guide stars stay so much steadier making guiding corrections substantially more positive.

I decided to test the system on a night of really rubbish seeing which was last night & tonight- tonight is especially bad with stars running a visual dance. Take a look at the sub below 8 mins through a red filter at a focal length of 1960 mm. I think it is pretty good & confirms potentially how good the new system will be. I will keep you posted how my testing carries on. The sub is not fully quality but will give you an idea but excuse the lack of calibration.

  

[Tinker1947]

The rings on the image could be dust on the sensor....

[pyrasanth]

The rings are most definitely dust in the imaging train. When I shoot the flats from last nights session I will give the optics a good clean as most of the dust can be seen visually in the optics so its bound to show in the pictures. 9 hours of exposure last night through a full set of LRGB filters and the final sub was as sharp as the first. Focus lock did a very good job.