iEXOS-100 slow slew rate in SharpCap


Having problems with SharpCap - the maximum rate I can set it to is 50x.

However, at 50x it moves at a rate of about 3 arcmins per second. So it will take 30 mins to rotate the head 90 degrees.

How can I get it to slew faster?

I can do a positional slew using NINA, and that works, but I can't do polar alignment in NINA.


Lloyd Simons


I'm not sure what you are trying to accomplish. If you are rotating the ra axis to do a sharpcap polar alignment you have to disengage the clutches and rotate manually. It's best to do this before you power the mount. You only need the camera connected to sharpcap. I use my guidecam.
Lloyd Simons
Mattawan, MI
Telescopes: Astrotech AT72ED II, Orion 8" Dobsonian, Tectron 15" Dobsonian, Celestron Super Polaris C8
Imaging Camera: Canon T3i
Guide Camera: QHY5L-IIM on a 60mm F4 Guidescope
Mounts: iExos-100 PMC-8, Vixen Super Polaris
Mount Control: KODLIX gn41 mini PC, Explorestars on a Lenovo Tab 2 A10-70F Android 6.0
Software: N.I.N.A. for imaging, PHD2 for guiding, Sharpcap for PA, Cartes du Ciel, PixInsight

Wade Prunty

Can sharpcap not control the mount to rotate it itself? I use the ASIAIR Pro polar alignment tool, which is extremely similar to sharpcap’s, and it rotates the RA dec itself during the polar alignment process.
Explore Scientific iEXOS-100
William Optics SpaceCat 51 APO
ZWO ASI1600MM Pro, ASI533MC Pro
Canon 5D, T3i (Both Astro Mods)
William Optics UniGuide


No, you have to rotate the mount yourself in SharpCap.

I like using the slew buttons because if you disengage the RA clutch you're likely to also knock the DEC axis a few degrees in the process - especially on a mount as small as this, and it will invalidate your polar alignment.

Anyway, rotating for polar alignment is not the only reason I don't want to spend an hour to move the scope from one side of the mount to the other.