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Below is a direct quote from a post by Andy Glasso of Open PHD Guiding Google Group fame.
An easy way get the scope pointed in the correct region of the sky for calibration is to slew RA until your counterweight bar is close to horizontal, then slew Dec until your scope tube is somewhat perpendicular to the mount's polar axis, like this picture:
It needn't be exact, anywhere in the vicinity of that orientation is fine.
So, instead of looking for a star that is near to both the Meridian and the Celestrial Equator, just slew your scope till it looks like this then calibrate away!
Cheers,
JT
∞ Primary Scopes: #1: Celestron CPC1100 #2: 8" f/7.5 Dob #3: CR150HD f/8 6" frac ∞ AP Scopes: #1: TPO 6" f/9 RC #2: ES 102 f/7 APO #3: ES 80mm f/6 APO ∞ G&G Scopes: #1: Meade 102mm f/7.8 #2: Bresser 102mm f/4.5 ∞ Guide Scopes: 70 & 80mm fracs -- The El Cheapo Bros. ∞ Mounts: iOptron CEM70AG, SW EQ6R, Celestron AVX, SLT & GT (Alt-Az), Meade DS2000 ∞ Cameras: #1: ZWO ASI294MC Pro #2: 662MC #3: 120MC, Canon T3i, Orion SSAG, WYZE Cam3 ∞ Binos: 10X50,11X70,15X70, 25X100 ∞ AP Gear: ZWO EAF and mini EFW and the Optolong L-eXteme filter ∞ EPs: ES 2": 21mm 100° & 30mm 82° Pentax XW: 7, 10, 14, & 20mm 70°
Searching the skies since 1966. "I never met a scope I didn't want to keep."
The PHD2 drift alignment tool will take you very close to the meridian and celestial equator as a first step in the alignment process if your scope is in the home position. Select drift alignment from the tools menu, click the slew button and away you go. It is the first place I go every session after doing a quick align from the HC menu.
For visual:
10" Skywatcher collapsible goto dob, various EP's and a Celestron StarSense auto align.
For imaging:
Orion 8" astrograph 800mm @ F3.9
Eq6-R Pro controlled by APT via EQmod with an OTA mounted mini PC
Tele Vue Paracorr Type 2 coma corrector
Altair Hypercam 26C
I recall reading somewhere that in addition to doing a good PA, choosing a calibration star that is close to 0°Declination is best. Choosing stars between 0-10° DEC, my average total RMS is normally between 0.2 & 0.3. Maybe a coincidence, but my scope/mount are ‘usually’ somewhere near the orientation pictured when calibrating. I will definitely try this, maybe save some searching. thank you JT!
Mike
Mike Chartrand Scopes: WO Star 71 Gen-II (F/4.9), Astro-Tech AT115EDT (F/7), Celestron 8" Edge HD (F/10) Cameras: ZWO ASI1600MM w/ Baader 1.25" LRGB & Narrowband Filters, ZWO ASI174MM mini, Starlight Xpress Lodestar X2 Mount: Skywatcher NEQ6 Pro Guiding: Orion ST-80 (f/5) w/ADM MiniMax (side-by-side), ZWO OAG Software: PHD2, Sequence Generator Pro, PixInsight Dark Site Transportation System: 2020 Telluride SX