xiongz
03-11-2024, 03:02 PM
After months of fixing my CEM60 mount, I finally got it run normally at desired accuracies and managed to snap a few hours of good data. As it is approaching late seasons for Helix, I thought it might be best to mix these few hours of data with fairly amount of earlier shots I got when the mount was faulty. Back in May I was experiencing irregular RA spikes and went on changing, one by one, tripod to a pier one, RA worm, and RA ring gear. As problems still persisted and were getting even worse, I couldn't think of anything else being wrong except for the motor or bearings. As I took apart RA worm again it was obvious the two bearings were faulty/worn. Quick change of the bearings immediately gave me around RMS 0.3 arcsec of guiding accuracy both in RA and DEC, which was huge relief for me as I was considering upgrading to a higher capacity one.
With the mount fixed I was only able to get two clear nights of imaging, with some 25x 10min subs of Ha and 13 sub of Oiii, ASI2600mm cooled to -15 degrees, 3nm Antlia filter, with a rebuilt Skywatcher 300F4 scope, OAG guiding. However, there were tens of hours of data when I was testing and fixing the mount as guiding errors for RA were about 1 while DEC was between 0.2-0.3. I removed or reduced stars of old images and used good stars from good Ha and Oiii of the past two week to get mixed results, which seemed to be quite ok. Here is HOSO image of about 46 hours in total, 170xHa, 43xOiii, and 64xSii. With HOSO I meant the blue channel was 50% Sii and 50% Oiii. I preferred this mixed colour as it would otherwise be either too blueish (HOO) or too yellowish (HOS) at the centre. I also used Ha as luminance to enhance overall details. Image was cropped and downsized by about 50% so it could be uploaded here.
Clear skies,
John
With the mount fixed I was only able to get two clear nights of imaging, with some 25x 10min subs of Ha and 13 sub of Oiii, ASI2600mm cooled to -15 degrees, 3nm Antlia filter, with a rebuilt Skywatcher 300F4 scope, OAG guiding. However, there were tens of hours of data when I was testing and fixing the mount as guiding errors for RA were about 1 while DEC was between 0.2-0.3. I removed or reduced stars of old images and used good stars from good Ha and Oiii of the past two week to get mixed results, which seemed to be quite ok. Here is HOSO image of about 46 hours in total, 170xHa, 43xOiii, and 64xSii. With HOSO I meant the blue channel was 50% Sii and 50% Oiii. I preferred this mixed colour as it would otherwise be either too blueish (HOO) or too yellowish (HOS) at the centre. I also used Ha as luminance to enhance overall details. Image was cropped and downsized by about 50% so it could be uploaded here.
Clear skies,
John