I am interested in purchasing one of these as well, so looking forward to your next report.
Where was it pointing when trying to calibrate, at the SCP or somewhere else. Usually it is recommended to point to the meridian on the celestial equator before beginning calibration.
I tried pointing at Peacock in the North East and the Celestial pole. The reason fir these choices was only that I didn’t have the counterweight bar attached and the system was way too heavy to not use one.
All ready for testing tonight. Software updated, counterweight on and balanced and set up in a more favourable location although Nundah is about 18 on the sky quality meter and there is a moon too.
I tried pointing at Peacock in the North East and the Celestial pole. The reason fir these choices was only that I didn’t have the counterweight bar attached and the system was way too heavy to not use one.
All ready for testing tonight. Software updated, counterweight on and balanced and set up in a more favourable location although Nundah is about 18 on the sky quality meter and there is a moon too.
I don't think you can calibrate on the SCP as there would be insufficient star movement for calibration. According to PHD2
• Get a good calibration, then re-use it – Within +/- 10 degrees of celestial equator, (Dec=0) – Within an hour of celestial meridian
So, last night was unsuccessful but I am not ready quite yet to blame the Staraid. I am coming to the view that it is in fact correct, there is no movement in DEC because the dec axis is quite simply not tracking on the EQ35 Pro mount!
This morning I had a thought that perhaps the orientation of the DEC axis mattered. Take a look at the two photos to see what I mean. AstroPete said though he didn't think which side the motor was on would impact tracking. Anyone? The mount is brand new.
This morning though I connected the mount in doors and did the initialisation in the synscan handset up to the point where it asked if I wanted to align and I said no then went to the Tracking in setup and selected Siderial. In theory then it is tracking. I left it running for an hour and the counterweight bar moved in that time but the dec puck didn't so I really do think it isn't tracking in Dec.
I took the plastic housing off and the gears look to be meshing and after all, it does slew and I see the gears working, but I left the plastic housing off and marked the position and nothing changed with time.
Once the mount is sorted, I'm optimistic the Staraid will perform. I have an open JIRA ticket with them but I have also told them the mount may not be tracking
So, last night was unsuccessful but I am not ready quite yet to blame the Staraid. I am coming to the view that it is in fact correct, there is no movement in DEC because the dec axis is quite simply not tracking on the EQ35 Pro mount!
>snip
I left it running for an hour and the counterweight bar moved in that time but the dec puck didn't so I really do think it isn't tracking in Dec.
Hi Chris
When the Mount is just tracking at the Sidereal rate, only the RA Motor is active, the DEC Motor is not being commanded to move.
The DEC Motor will only activate and slew the Mount in Declination during a GoTo, a manual button push of the DEC Buttons or an auto guider correction command when auto guiding is active.
Thanks for the write ups, it looks like an interesting device.
When the Mount is just tracking at the Sidereal rate, only the RA Motor is active, the DEC Motor is not being commanded to move.
The DEC Motor will only activate and slew the Mount in Declination during a GoTo, a manual button push of the DEC Buttons or an auto guider correction command when auto guiding is active.
Thanks for the write ups, it looks like an interesting device.
Cheers
Dennis
Hi Dennis, I don’t understand that. It has a dec axis and guiding happens in both axis right? If dec plays no part in tracking why would guiding in dec ever take place? On the Star Adventurer et al you can only guide in RA but on a full mount you have both enabled.
Hi Dennis, I don’t understand that. It has a dec axis and guiding happens in both axis right? If dec plays no part in tracking why would guiding in dec ever take place? On the Star Adventurer et al you can only guide in RA but on a full mount you have both enabled.
If you are perfectly polar aligned the mount only needs to rotate in RA. Of course you will normally be a bit off and the mount may have error so guiding is done in both RA and DEC.
Hi Dennis, I don’t understand that. It has a dec axis and guiding happens in both axis right? If dec plays no part in tracking why would guiding in dec ever take place? On the Star Adventurer et al you can only guide in RA but on a full mount you have both enabled.
Hi Chris
There is Tracking and their is Guiding.
Tracking:
The Earth rotates once per day (23H 56M) on its axis and the RA Motor drives the RA Axis at this Sidereal Rate to compensate for the Earth's rotation and thus "keep up" with the stars.
If you are Polar Aligned, the DEC Axis should not need to be moved by the DEC Motor as the Earth's rotation is in RA and not DEC.
Guiding
Here, the mount is Tracking at the Sidereal Rate, but is also being additionally controlled by an Autoguider System which is monitoring a (calibrated) Star. If this Star drifts off the Calibrated Pixel(s), then the Autoguider SW will command the RA Motor and/or DEC Motor to make a (hopefully) tiny movement to return the Star to its Calibrated Pixel(s). This happens "on top" of the constant rate Tracking, via the RA Motor, which is just chugging along at 1 Revolution per Sidereal Day.
Tracking is "unintelligent" in that the RA Motor just purrs along to compensate for the Earth's daily rotation.
Autoguiding in "intelligent" in that it is taking feedback from the Autoguider System to nudge the mount to make small corrections to keep a Guidestar on a designated Pixel.
This is also why you cannot calibrate close to the pole. If you draw circles based on DEC around the pole you see that the circumference of these circles gets bigger the further away you are from the pole. Since a guide pulse is the same length wherever you are pointing, a pulse close to the pole results in less 'apparent' movement than a pulse on the equator.
Auto calibration routines need to get a good estimate of a stars movement when sending the pulse. This is called calibration and if you are calibrating close to the pole the absolute movement of the star is not good enough to calibrate.
Your first guiding calibration should be on the meridian within 20 degrees of DEC 0 (the equator). This is what is recommended by PHD2 and my ASIAir pro which includes a guiding feature. Not sure how StarAid overcomes this if it doesn't keep a calibration so YMMV.
Thanks Dennis/Zuts, yes that makes perfect sense. The odd thing is I haven't had calibration issues since the days of trying to use the SBIG software for guiding back when I had an ST2000 about 14 years ago. CCDSoft or CCDPOps I think it was was incredibly fussy and couldn't cope with things not being orthogonal.
Today we are used to PHD which doesn't seem fussy at all. I previously used the ASIAir with its version of PHD for guiding with the EQ35 (a previous EQ35 pro) and it always just worked no matter whether the scope was pointing towards the celestial pole or not.
It may be that Staraid is a bit less tolerant. I'm sure I did try with the camera (and therefore guidescope too) pointing elsewhere and it still failed to calibrate.
More than that it also failed to platesolve. I took a screen snip of what the camera captured when it then gave me the message "can't recognise the stars"! There are plenty of stars - this was looking towards peacock - Almost any software would plate solve that as a jpeg.
When the Mount is just tracking at the Sidereal rate, only the RA Motor is active, the DEC Motor is not being commanded to move.
The DEC Motor will only activate and slew the Mount in Declination during a GoTo, a manual button push of the DEC Buttons or an auto guider correction command when auto guiding is active.
Thanks for the write ups, it looks like an interesting device.
Cheers
Dennis
Yes I got it working once. I’m trying again as we speak. This time with the dec axis motor on the same side as the RA motor and I have everything pointed to somewhere near Antares. It simply fails calibration because it says there’s no movement in Dec. see pic.
At the moment, as much as I’d love to give this device a ringing endorsement, I simply can’t just yet. I have now spent three nights trying to get this thing work in vain.
I’m more than happy to accept I’m doing something silly but this device is extremely simple in essence. Connect to the guidescope and ensure it is focused, turn it on and do nothing else except image.
Plate solving is really hit and miss and completely confusing too. For example I click the ‘Recognise’ button and it starts capture and platesolving and 99 times out of 100 it will fail but if you go to another screen then back it tells you what your location as if it was successful all along! When it is successful I think great and click the polar alignment screen and it begins to platesolve again, but now if fails! Two seconds ago is platesolved the same patch of stars successfully - nothing changed but now it fails.
Random moving of the scope to different parts of the sky brings differing levels of success. If that’s what the problem is, I.e. it requires a very specific set of parameters, angles etc, it is simply too intolerant of regular conditions to be useful.
I look forward to hearing from Staraid themselves. I sent them the log file as re
Requested.
At the moment, as much as I’d love to give this device a ringing endorsement, at the moment I simply can’t. I have now spent three nights trying to get this thing work in vain.
I’m more than happy to accept I’m doing something silly but this device is extremely simple in essence. Connect to the guidescope and ensure it is focused, turn it on and do nothing else except image.
Plate solving is really hit and miss and completely confusing too. For example I click the ‘Recognise’ button and it starts capture and platesolving And 99 times out of 100 it will fail but if you go to another screen then back it tells you your location as it was successful all along! When it is successful I think great snd click the polar alignment screen snd it begins to platesolve again but now if fails! Two seconds ago is platesolves the same patch of stars successfully - nothing changed but now it fails.
Random modelling the scope to different parts of the sky brings differing levels of success. If that’s try it is simply too intolerant of regular conditions to be useful.
I look forward to hearing from Staraid themselves. I sent them the log file as re
Requested.
Chris
I had high hopes for this, good luck and hope it all works out. Maybe you can find someone in Brisbane and try it on their setup...
I had high hopes for this, good luck and hope it all works out. Maybe you can find someone in Brisbane and try it on their setup...
I need to try a shorter focal length guidescope because even their own documentation says you should use between 100mm and 130mm and implies problems at longer focal lengths. I’m reluctant to spend another $100 on a piece of kit based on only a chance that would fix it. Perhaps I can find someone who has one to try it out.
I forgot to mention that on the autoguiding front I tried turning off DEC guiding and that made it work every time. I'm still uncertain therefore if that means there could be something wrong with the DEC axis of my mount or not.
At the moment, as much as I’d love to give this device a ringing endorsement, I simply can’t just yet. I have now spent three nights trying to get this thing work in vain. .....
Chris
When troubleshooting gear for clients I go back to basics. i.e. to check the Dec drive is working actually look through an eyepiece while you press the Dec button (at guide rate) and check for positive star movement. Check the reverse direction for backlash etc.
Then exercise the autoguider to do the same. It doesn't take long to suss out what's going on.
That said, if this puppy is not working as advertised, I feel your pain. It's not the result you'd expect from that sort of investment.
When troubleshooting gear for clients I go back to basics. i.e. to check the Dec drive is working actually look through an eyepiece while you press the Dec button (at guide rate) and check for positive star movement. Check the reverse direction for backlash etc.
Then exercise the autoguider to do the same. It doesn't take long to suss out what's going on.
That said, if this puppy is not working as advertised, I feel your pain. It's not the result you'd expect from that sort of investment.
Thanks Peter. The DEC buttons definitely produce movement but are you saying set the mount tracking to guide speed (which means RA and Dec) and watch the star?
The other thing I have thought of doing is to borrow a regular guide camera off someone and attach it to my guidescope and use PHD with the laptop just to confirm calibration happens. If it does, the Staraid calibration process is just too fussy and if it doesn't the mount itself may have problems.
Thanks Peter. The DEC buttons definitely produce movement but are you saying set the mount tracking to guide speed (which means RA and Dec) and watch the star?
".......
Yes, set the mount to guide speed, then activate each Dec and RA relay in turn, while doing a visual check on a starfield that things are actually moving.
While gears and motors can turn, if you have a slipping clutch, binding shaft, whatever, not much will happen at the business end.
