Original Eyepieces
Baader 1.25/2" 8-24mm Hyperion Clickstop Mark IV Zoom
Svbony 1.25" 10mm 62 deg Aspheric
Svbony 1.25" 23mm Celestron Aspheric
Svbony 1.25" 9.7mm Plossl 52 Deg
Svbony 1.25" 26mm Plossl 52 Deg
Svbony 1.25" 32mm Plossl 46 Deg
Svbony 1.25" 40mm Plossl 40 Deg
Celestron 1.25" 12.5mm Plossl 40 Deg CrossAim Reticle
(2) Celestron 2" Luminos 23mm (.91”) 82 Deg 6-Element Wide Angle 2 lbs
Televue 2" 55mm Plossl 50 Deg
Tricked Out Eyepieces
Baader 1.25/2" 8-24mm Hyperion Clickstop Mark IV Zoom
16-48mm
Svbony 1.25" 10mm 62 deg Aspheric
20mm
Svbony 1.25" 23mm Celestron Aspheric
46mm
Svbony 1.25" 9.7mm Plossl 52 Deg
19.4mm
Svbony 1.25" 26mm Plossl 52 Deg
52mm
Svbony 1.25" 32mm Plossl 46 Deg
64mm
Svbony 1.25" 40mm Plossl 40 Deg
80mm
Celestron 1.25" 12.5mm Plossl 40 Deg CrossAim Reticle
25mm
(2) Celestron 2" Luminos 23mm (.91”) 82 Deg 6-Element Wide Angle 2 lbs
46mm
Televue 2" 55mm Plossl 50 Deg
110mm
Of particular interest are the 80mm and 110mm focus combinations. Given the Celestron C9.25" OTA with 234.95mm aperture and 2350mm focal length, the resultant combos are f/3.1 and f/2.3.
8" f6 = 48" fl 2" fl EP = 24" FL 24/8 = F3 example reference
9.25" F10=92.5" FL 3.2" FL EP = 28.9" FL 28.9/9.25=F3.1
4.3" EP = 21.5 21.5/9.25=F2.3
If the focus works out, stacking two focal reducers for about $20 will give f/1.6 and f/1.2.
A HyperStar goes down to f/2.2 for a cost of $1199.00. Using my approach for $20, f/1.2 is possible, and for $10, f1.6 is possible. I highly recommend the f1.6 system.
https://starizona.com/store/hyperstar-9-25-v4
