GRAN TURISMO 71 F/5.9 APO TRIPLET
William Optics
Apochromatic triplet
2.95 kg
GRAN TURISMO 71 F/5.9 APO TRIPLET - Gold / OTA Only is backordered and will ship as soon as it is back in stock.
The William Optics Gran Turismo 71 is a three element apochromatic refractor with a focal ratio of f/5.9 and a focal length of 419mm. Utilizing FPL-53 synthetic fluorite glass, this telescope provides excellent aberration correction.
The 2.5" 10:1 rack & pinion focuser is smooth, stable and reliable, providing no slippage over long imaging sessions. The new CNC-machined and anodized handle bar with finder-style saddle is perfect for attaching a guide scope or other accessories. The Gran Turismo 71 also includes William Optics' innovative clear Bahtinov mask integrated into the lens cap.
William Optics uses high quality steel lens cells for their Gran Turismo and FLT triplet refractors. This is perfect for temperature compensation and will prevent pinched optics in cold weather conditions.
For best imaging results, it is recommended to pair the Gran Turismo 71 with its matching Flat6AIII 0.8x field flattener.
Note: As the Flat6AIII an adjustable flattener, you must adjust the distance for your specific telescope. See the Instructions tab above.
Specifications
Optical design |
Apochromatic triplet |
Objective diameter |
71 mm |
Focal length |
419 mm |
Focal ratio |
f/5.9 |
Image circle |
44.4 mm (with Flat6AIII field flattener) |
Compatible flattener |
William Optics Flat6AIII |
Mount attachment |
210 mm Vixen-style/Arca-Swiss dovetail bar |
Focuser |
Rack & pinion dual speed (10:1) 2.5" diameter |
Camera connection |
M63 x 1, 2" |
Backfocus |
64.1 mm (with flattener/reducer) |
Tube weight |
2.95 kg (including accessories) |
Tube length |
392 mm (fully retracted), 470 mm (fully extended) |
Tube diameter |
TBA |
Dew shield diameter |
TBA |
SKU |
WO-A-F71GTII (Gold - without flattener), WO-A-F71GTII-AP (Gold - with flattener), WO-A-F71GTIIRD (Red - without flattener) |
Included items
- Gran Turismo 71
- Lens cap with Bahtinov mask
- Finder saddle handle bar
- 210 mm Vixen-style dovetail bar
- Soft carry case
Instructions
Note: Once you have unscrewed the rear adapter to the appropriate value in the table below, the remaining backfocus distance to make up will be 55mm from the rear M48 thread.
Distance adjustment needed for correct backfocus
GT71 |
9.1 mm |
---|---|
GT81 |
7.1 mm |
Z81 |
5.2 mm |
Z103 |
2.5 mm |
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Optical design
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Aperture
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Focal length
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Focal ratio
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Image circle
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Backfocus64.1 mm with Flat6AIII
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Focuser type
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Tube diameter
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Dew shield diameter
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Weight