SharpCap Forums

Hi,

the wording is definitely tricky. Max move size doesn't feel right, since it is not a limit on how big a move the correction will make, it is a limit on how much movement will be considered as 'bad data' and put the system into standby. I am going to try 'excessive movement' to see how that feels. There is a tooltip (deliberately, since the naming was hard).

The tracking lost setting is in seconds (much easier to implement and more consistent that way). I even got it right in the text to the right of the value, but goofed the tooltip - well spotted!

cheers,

Robin

Hi Robin

Yes, I think that 'excessive movement' conveys the intent much better. I take it the value is based on comparison with the original position, i.e. when guiding was first started, not from the most recent value, is that correct?

Thanks for the clarification on the tracking lost value.

Scope's out today, but completely clear skies so can't get any further with testing.

M

Hi,

the excessive threshold applies to the currently calculated 'correction needed' - ie the distance between where the center of mass is and where it should be. The 'where it should be' is where it was when you started tracking, as I think you noted earlier in this thread.

cheers,

Robin

Hi Robin

A quick update, I'm now using version 4.0.9420 and I see you've clarified the 'Tracking lost after' units and the new 'Excessive movement size' label.

Today has been ideal conditions for testing, some clear sky, some larger clouds and then completely mist covered, I live at the west end of the Isle of Wight and sea mist/fog is always a problem at this time of year.

The Feature tracking is working very well, I've set the 'Excessive movement size' to 250px and the 'Tracking lost after' to 300s. I never lost the sun out of frame, and it stayed mostly around the centre position no matter what the sky was doing. Even after the image was totally black, when the Sun reappeared it was always within limits.

I think the use I'm putting it to for Solar Prominence time lapse imaging, the tool is working perfectly, so thanks for taking the time to make the changes.

All the best
Mike

Hi Mike,

glad to hear that is working nicely for you. Do you get clear dark skies to the south of you out there on the IoW? Was out there for a holiday about 4 years ago and really enjoyed visiting

cheers,

Robin

Hi Robin

Yes, the southwest side of the Island is very dark, roughly from the Needles in the west to Blackgang in the east, I'm in the centre of Freshwater so I don't enjoy such good seeing, mainly due to surrounding 'security' lighting and the all too blue LED streetlights.

The Island is going for 'Dark Sky' accreditation, but I'm not sure how far along they are with it. It mainly covers the southwest and my location will be just north of the zone. But I wonder if it's all too late with thousands of Starlink, and other satellites already affecting imaging and it seems like it'll only get worse.

Mike

Hi Mike,

yes, starlink can be a pain, but should be less of an issue in the winter - that's because when the sun is a long way below the horizon then the satellites themselves are also in the Earth's shadow as they pass over head. It's a problem when the sun is below the horizon from the point of view of the observer but still near enough that it can illuminate the satellite.

Of course there's also SharpCap's satellite trail removal tool

clear skies!

Robin

Hi Robin

Your 'Satellite Trail Removal' tool is something that has passed me by, I'll have to check it out.

Mike

HI Robin
I am getting started in Solar imaging now that the sun is getting so active.
I have been trying to use your Feature tracking in ROI mode.
I am using a ASI178 camera on a Lunt 60mm solar scope to image the prominences.
To image the prominence, I usually run in a ROI of 800x600 which leaves plenty of room to have the ROI track.
My RST135 mount is PA close enough to keep the prominence in FOV for about 40 minutes, as it moves in FOV.
When I use Feature ROI tracking, the MONITORING seems to pick up the prominence OK (little boxes on the feature)
I then Trigger Calibration.
Calibration completes and the GUIDE button is enabled.
I trigger GUIDE.
SC adjusts the ROI position OK for maybe a minute then it seems to quit tracking/reacting.
The prominence is fully in the center parts of the FOV. Not close to the edge.
The prominence drifts off and it will not adjust the ROI
There is plenty of FOV for the ROI to remain centered on the prominence.
I do note that the Accumulated Movement graph shows a lot of vectors, not all in the same direction.
Maybe the image/feature turbulence causes the tracking algorithm to "fail" and it quits trying?
Any suggestions?
NOTE
I tried using Feature tracking with control of the RST135 mount. (ASCOM interface)
SC seemed to have a problem with the Slew control.
When I enabled the Calibration in mount mode , the mount would slew way out of FOV and never recover.
I don't believe I tried this with the sun in full FOV. Just with prominences.

Thanks
Stephen

Hi Stephen,

the first thing I would suggest is to try using the SharpCap 4.1 beta - I have been tweaking and improving the feature tracking in the beta, so you may see better results. You can find download links in the Beta testing forum : viewforum.php?f=38

With the loss of tracking after a few minutes, it does sound possible that the image analysis is gradually losing the tracking points until there are not enough to follow the movement of the image. The number of tracking points currently active is shown just below the 'Accumulated movement' figures in the monitoring status area. There is also information stored in both the main SharpCap log and the 'Guiding Log' file (saved in the same folder as the main log) that may help track down why the guiding has stopped.

For the mount movement tracking, the beta has multiple improvements that might help - you can also adjust the speed used for movement when using the mount - picking the right speed is important, since very low speeds make calibration and corrections slow, while high speeds can lead to the 'everything moves out of view really quickly' problem.

cheers,

Robin