autoguiding query

[it344x]

I have re-seated my spotter & guidescope to sit centrally (as opposed to at the end of the scope) and diametrically opposite to the camera, in a bid to optimise my overall balance, due to my excellent (but heavy and long) Intes Micro MN86 sitting on my CEM60EC.
This actually worked very well, and last night I could move the system with a feather with the clutches released.
However last night I was getting the following drift/correction taking place which resulted in slightly stretched stars, but iPolar was constantly checked to remain green.
Image gathering and guiding all in AstroArt 7, trius 814 camera with lodestar, image reduced to 66% and cropped - basic image processing in AA only (15 x 300 sec).
I think it may be more guiding than mount, however if anyone have any ideas/recommendations on what may be happening here, I'd be grateful. I re-calibrated autoguiding and reduced the pulsing, and still get this.

[Iver]

I'm just guessing, since you said your balance was so perfect it might be a slight bit of play in the worm. You may want to try keeping your balance slightly heavy to the East.

[fabdev]

Hi, about "reduced the pulsing", which option exactly ? By the way, I suggest to reset all autoguide settings (click the 3 buttons "Default values") and repeat the calibration (is it normal that RA is 2X faster than DEC?)

[Dunmunro]

I have re-seated my spotter & guidescope to sit centrally (as opposed to at the end of the scope) and diametrically opposite to the camera, in a bid to optimise my overall balance, due to my excellent (but heavy and long) Intes Micro MN86 sitting on my CEM60EC.
This actually worked very well, and last night I could move the system with a feather with the clutches released.
However last night I was getting the following drift/correction taking place which resulted in slightly stretched stars, but iPolar was constantly checked to remain green.
Image gathering and guiding all in AstroArt 7, trius 814 camera with lodestar, image reduced to 66% and cropped - basic image processing in AA only (15 x 300 sec).
I think it may be more guiding than mount, however if anyone have any ideas/recommendations on what may be happening here, I'd be grateful. I re-calibrated autoguiding and reduced the pulsing, and still get this.

Are you using a guidescope or an OAG?


Hi, I have a CEM60 non-EC. I use a .25x guide rate for both axis. However, I have noted that the mount is quite sensitive to having the gear switch knob set to an optimal position so it might be worthwhile to adjust that and test the effect on guiding. Also the latest firmware has optimized the autoguiding response. I would suggest that the mount be perfectly balanced and not be biased east or west because the worm is magnetically loaded for zero backlash.

Unfortunately, with the current pandemic, I haven't been able to visit my observatory for sometime.

[it344x]

Hi, about "reduced the pulsing", which option exactly ? By the way, I suggest to reset all autoguide settings (click the 3 buttons "Default values") and repeat the calibration (is it normal that RA is 2X faster than DEC?)

hi Fabdev,
I Mean by increasing the "pause after pulse" value.
I will double check that I repeat the calibration when I see this. I think I might be over observing the guiding, and I am making the system overreact to atmospheric distortion - I will try longer gaps with longer exposures too.
Many thanks for the advice.

[it344x]

I have re-seated my spotter & guidescope to sit centrally (as opposed to at the end of the scope) and diametrically opposite to the camera, in a bid to optimise my overall balance, due to my excellent (but heavy and long) Intes Micro MN86 sitting on my CEM60EC.
This actually worked very well, and last night I could move the system with a feather with the clutches released.
However last night I was getting the following drift/correction taking place which resulted in slightly stretched stars, but iPolar was constantly checked to remain green.
Image gathering and guiding all in AstroArt 7, trius 814 camera with lodestar, image reduced to 66% and cropped - basic image processing in AA only (15 x 300 sec).
I think it may be more guiding than mount, however if anyone have any ideas/recommendations on what may be happening here, I'd be grateful. I re-calibrated autoguiding and reduced the pulsing, and still get this.

Are you using a guidescope or an OAG?


Hi, I have a CEM60 non-EC. I use a .25x guide rate for both axis. However, I have noted that the mount is quite sensitive to having the gear switch knob set to an optimal position so it might be worthwhile to adjust that and test the effect on guiding. Also the latest firmware has optimized the autoguiding response. I would suggest that the mount be perfectly balanced and not be biased east or west because the worm is magnetically loaded for zero backlash.

Unfortunately, with the current pandemic, I haven't been able to visit my observatory for sometime.

hi Dunmunro,
It is a guidescope.