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First off, thank you for that detailed analysis Jerry, appreciated.
The old post was an interesting read, I appreciate the difficulty of making changes to the chip and it sounds like increasing the current to the motor might be an option.
The first video I attached was made with a Meade LX65 Cassegrain @ 1900mmFL x 127mm. I think I used a 25mm eyepiece and my trusty Celestron Neximage CCD at 720x480 @ 25 FPS. I may have used my 2x doubler but I don't recall for sure, sorry.
The iexos is on the latest firmware. Although I was managing the mount via the ASIAir, the camera was plugged directly into my laptop. I recall switching the ASIAir tracking mode between Sidereal and Lunar tracking to see if the issue would go away and it was present in both modes.
I can try and provide more information - just let me know what you need.
I agree with your comments; I don't notice the oscillation issue when imaging with my wider-field Orion 80x400mm refractor. The scope is over 30 years old and I'm still getting nice round stars and 2-3min guided exposures using the iExos. I could probably push it even longer and have similar success. To your point, I only notice the issue with the higher focal length LX65, narrower field of view with planetary/lunar viewing/video.
The LX65 is about 6.2Lbs and I needed both counter-weights almost fully extended to balance the mount. I feel confident the balance was fairly good but find there's some friction with the mount when trying to balance so it's as good as I could get it.
I also thought that the increased mass/inertia of the bigger scope and perhaps slight off-balance configuration might contribute to making a small issue have a bigger than normal impact visually.
My goal for that evening was to try and learn how to stack video to produce some nice pictures of the moon and perhaps Jupiter using this video-stacking technique when the oscillation became apparent.
We had already started this thread when I received the LX65 so I wasn't too worried if the issue should appear as others had indicated I could stack/process the issue away.
However, we were just viewing the Moon and Jupiter (and for that the long FL and magnification is required) and people were looking through the eyepiece and amazed at the clarity but then looked up and said, 'Why's it wobbling?'
I felt a little silly trying to explain it - lol.
It's like trying to explain why the radio doesn't work on your brand-new Ferrari - lol.
It still goes really fast but it's still annoying :)
I get this hobby is technical and has a learning curve and requires practice and tinkering - that's kinda why I like it.
But I'm hoping we can get this sorted out.
@ Wes, i'm going to do some digging and see if I can determine what's driving the ASIAir (ASCOM or other) and what exactly happens between Sidereal and Lunar tracking - I don't see a 'Point' mode for the ASIAir.
ZWO just released a new firmware version with a video mode so I'll see if this issue persists. I'm aware we don't want to turn this into a third-party discussion but it seems others have noticed the issue with different non-ASI configurations.
Jerry, if there's a way to increase the current to the mount to minimize this, then I'm willing to try. Previous comments about power consumption when on battery noted.
On Sat, Oct 3, 2020 at 11:05 AM Jerry Hubbell - Explore Scientific VP Engineering <jrh@...> wrote:
On Fri, Oct 2, 2020 at 09:11 PM, Mario wrote:
Mounts: iExos 100, Skyguider Pro
Scopes/Lenses: Main/Orion 80mm, DSLR/Tamron 18-400mm lens, guide/ZWO-340A
Cameras: Canon T2i DSLR, ZWO120MM (guide)
Utility Software: iPolar (for Skyguider polar alignment), iCap, Explorestars, Canon EOS Utility
Image Processing Software: Photoshop