Model building survey time. As there are a reasonable number of 10Micron mount owners that visit here I thought it would be useful to survey how you build a model and what the unguided results you are getting. I'll list what parameters might be useful then I'll state my results with my two mounts.
A) 10Micron mount model (1000, 2000, etc)
B) Type of scope (refractor, reflector, SCT etc)
C) Mount firmware
D) Software used to assist building model (with associated software) - or if hand built using keypad/astrometric eyepiece
E) Typical number of stars in model
F) Typical polar align error
G) Image scale in arc sec per pixel
and for results
H) Typical pointing RMS
I) Typical length of reliable unguided imaging
For my GM1000HPS I get:
B) Type of scope: Refractor (TV85)
C) Firmware: 2.16.12
D) Model building method: Hand built model
E) Star/point count: 20 - 25
F) Typical polar error: 15"
G) Image pixel scale: 1.5"
H) RMS: 10" - 15"
I) Reliable Unguided time: 10 minutes - very rare to discard frames. Not really tried longer due to light pollution limits at home.
For my GM2000HPS I get:
B) Type of scope: Refractor (Tak TOA130)
C) Firmware: 2.16.12
D) Model building method: Mount Wizard 3 with SGPro for image acquisition and ANSRV for plate solving and the Per Frejvall 10Micron mount ASCOM driver
E) Star/point count: 85+
F) Typical polar error: 10" - 12"
G) Image pixel scale: 1.3"
H) RMS: 5" - 8"
I) Reliable Unguided time: 10 minutes - very rare to discard frames. Not really tried longer as this is sufficient for LRGB frames at my dark site and my narrow band frames typically start at 20 minutes up to 2 hours so I use hybrid guiding (unguided (dual tracking) with very low rate guiding on top)
These are my virtually bomb proof unguided limits (99+%). I also find that my unguided images (10 minutes and under) have slightly sharper detail than if I guided so I preferentially go unguided under 10 minutes.
Note that I have decided to use medium focal length rigid refractors as my workhorses. I guess the real test comes with much longer focal lengths and with mirror scopes so I'm interested in those results
Also I've never really studied at what point unguided imaging starts to break down and become unreliable - for my purposes, and with site/system limits, unguided works for me reliably up to 10 minutes
Edited by Tonk, 26 February 2021 - 06:57 AM.