Sky-Watcher SKU: S11220 | Helix SKU: CTS11220
SKU | S11220 |
UPC | 050234112208 |
Optical Info | |
---|---|
Optical Design | Newtonian |
Mirror Coatings | 94% Aluminum |
Glass Type | Borosilicate |
True Aperture (mm) | 257 |
Primary Aperture (mm) | 254 |
F/Ratio | 4 |
Focal Length (mm) | 1000 |
Secondary Diameter | 89mm |
Secondary Obstruction (by diameter) | 35% |
Secondary Obstruction by Area | 12% |
Observational Info | |
Dawes Limit | 0.46 |
Rayleigh Limit | 0.55 |
Limiting Mag. | 14.5 |
Minimum Magnification | 36 |
Maximum Magnification | 500 |
Light Gathering (compared to next size down) | 57% |
General Info | |
Focuser | 2" Dual Speed Crayford |
OTA Length (Retract/Ext.) | 36.5" |
OTA Outer Diameter | 11.375" |
OTA Weight (with accessories) | 36.5 |
Accessories | |
Included Finder | 9x50 Finder |
Included Diagonal | No |
Mounting Accessories | Rings/V-Rail |
Included Eyepieces | None |
Included Case | No |
Corrector | No (optional) |