William Optics Adjustable Field Flattener 68III
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This revolutionary new WO FF68III Adjustable Flattener was made for 6 -7.5 F ratio refractors.
This high-quality flattener has been engineered and CNC machined for usage with our FLT 98, 120, 132, GT102 and other APO refractors.
This accessory is a must-have for refractor astrophotography.
Lens
- Designed to cover full size DSLR cameras with clear lens aperture of 50 mm
- STM coated with an excellent doublet air spaced design.
- Produced entirely with the best Ohara optical glasses.
- Flattener Power: 1x (no reduction).
- 45mm for full illuminated imaging circle.
Amazing
- It will flatten the field amazingly well and finally make you see those stars round!
- This unique flattener works with WO or other 6-7.5 F ratio refractors.
Superb Finish
- Superb William Optics anodized finish.
- All internal surfaces threaded and blackened for no reflections.
- Protecting covers are included on both sides.
Easy to Use
- Will accept any standard T-ring for your camera (thread size M48x0.75). Not for use with smaller 42mm M42x0.75 T rings.
- Suitable for GT81 WIFD, FLT98, FLT120, FLT132, GT102 (with 3" focuser) and many others refractors with focuser M92x1.0 thread.
Compatibility:
- Gran Turismo 81 + Back Adapter # AD-M80-54-M48
- Back Focus: 57.0mm
- Adjust Distance: 2.0mm
- Image Circle: ∅44.4mm
- Gran Turismo 102
- Back Focus: 68.6mm
- Adjust Distance: 13.6mm
- Image Circle: ∅44.4mm
- Gran Turismo 153
- Back Focus: 57.8mm
- Adjust Distance: 2.8mm
- Image Circle: ∅44.4mm
- Zenithstar 126
- Back Focus: 58.0mm
- Adjust Distance: 3.0mm
- Image Circle: ∅43.4mm
- Fluorostar 91 + Back Adapter # AD-M80-45-M48
- Back Focus: 60.0mm
- Adjust Distance: 5.0mm
- Image Circle: ∅43.4mm
- Fluorostar 120
- Back Focus: 65.7mm
- Adjust Distance: 10.7mm
- Image Circle: ∅44.4mm
- Fluorostar 132
- Back Focus: 62.7mm
- Adjust Distance: 7.7mm
- Image Circle: ∅44.4mm
- Fluorostar 156
- Back Focus: 57.6mm
- Adjust Distance: 2.6mm
- Image Circle: ∅44.4mm
Specifications:
- Lens Type: 2 Groups 2 Elements
- Length: 64.5 mm
- Telescope Thread: M92 x 1 x 6.5 mm
- T-mount Thread: M48 x 0.75 x 4 mm
- T-mount Supported: Canon EF, RF; Nikon F, Z; Sony E; Pentax K; MFT (M4/3); FUJI X
- Camera Format; > Full Frame
- Weight: 718.2 g / 1.6 lbs
Other Information
- Country of Manufacture: Taiwan
This revolutionary new WO FF68III Adjustable Flattener was made for 6 -7.5 F ratio refractors.
This high-quality flattener has been engineered and CNC machined for usage with our FLT 98, 120, 132, GT102 and other APO refractors.
This accessory is a must-have for refractor astrophotography.
Lens
- Designed to cover full size DSLR cameras with clear lens aperture of 50 mm
- STM coated with an excellent doublet air spaced design.
- Produced entirely with the best Ohara optical glasses.
- Flattener Power: 1x (no reduction).
- 45mm for full illuminated imaging circle.
Amazing
- It will flatten the field amazingly well and finally make you see those stars round!
- This unique flattener works with WO or other 6-7.5 F ratio refractors.
Superb Finish
- Superb William Optics anodized finish.
- All internal surfaces threaded and blackened for no reflections.
- Protecting covers are included on both sides.
Easy to Use
- Will accept any standard T-ring for your camera (thread size M48x0.75). Not for use with smaller 42mm M42x0.75 T rings.
- Suitable for GT81 WIFD, FLT98, FLT120, FLT132, GT102 (with 3" focuser) and many others refractors with focuser M92x1.0 thread.
Compatibility:
- Gran Turismo 81 + Back Adapter # AD-M80-54-M48
- Back Focus: 57.0mm
- Adjust Distance: 2.0mm
- Image Circle: ∅44.4mm
- Gran Turismo 102
- Back Focus: 68.6mm
- Adjust Distance: 13.6mm
- Image Circle: ∅44.4mm
- Gran Turismo 153
- Back Focus: 57.8mm
- Adjust Distance: 2.8mm
- Image Circle: ∅44.4mm
- Zenithstar 126
- Back Focus: 58.0mm
- Adjust Distance: 3.0mm
- Image Circle: ∅43.4mm
- Fluorostar 91 + Back Adapter # AD-M80-45-M48
- Back Focus: 60.0mm
- Adjust Distance: 5.0mm
- Image Circle: ∅43.4mm
- Fluorostar 120
- Back Focus: 65.7mm
- Adjust Distance: 10.7mm
- Image Circle: ∅44.4mm
- Fluorostar 132
- Back Focus: 62.7mm
- Adjust Distance: 7.7mm
- Image Circle: ∅44.4mm
- Fluorostar 156
- Back Focus: 57.6mm
- Adjust Distance: 2.6mm
- Image Circle: ∅44.4mm
Specifications:
- Lens Type: 2 Groups 2 Elements
- Length: 64.5 mm
- Telescope Thread: M92 x 1 x 6.5 mm
- T-mount Thread: M48 x 0.75 x 4 mm
- T-mount Supported: Canon EF, RF; Nikon F, Z; Sony E; Pentax K; MFT (M4/3); FUJI X
- Camera Format; > Full Frame
- Weight: 718.2 g / 1.6 lbs
This revolutionary new WO FF68III Adjustable Flattener was made for 6 -7.5 F ratio refractors.
This high-quality flattener has been engineered and CNC machined for usage with our FLT 98, 120, 132, GT102 and other APO refractors.
This accessory is a must-have for refractor astrophotography.
Lens
- Designed to cover full size DSLR cameras with clear lens aperture of 50 mm
- STM coated with an excellent doublet air spaced design.
- Produced entirely with the best Ohara optical glasses.
- Flattener Power: 1x (no reduction).
- 45mm for full illuminated imaging circle.
Amazing
- It will flatten the field amazingly well and finally make you see those stars round!
- This unique flattener works with WO or other 6-7.5 F ratio refractors.
Superb Finish
- Superb William Optics anodized finish.
- All internal surfaces threaded and blackened for no reflections.
- Protecting covers are included on both sides.
Easy to Use
- Will accept any standard T-ring for your camera (thread size M48x0.75). Not for use with smaller 42mm M42x0.75 T rings.
- Suitable for GT81 WIFD, FLT98, FLT120, FLT132, GT102 (with 3" focuser) and many others refractors with focuser M92x1.0 thread.
Compatibility:
- Gran Turismo 81 + Back Adapter # AD-M80-54-M48
- Back Focus: 57.0mm
- Adjust Distance: 2.0mm
- Image Circle: ∅44.4mm
- Gran Turismo 102
- Back Focus: 68.6mm
- Adjust Distance: 13.6mm
- Image Circle: ∅44.4mm
- Gran Turismo 153
- Back Focus: 57.8mm
- Adjust Distance: 2.8mm
- Image Circle: ∅44.4mm
- Zenithstar 126
- Back Focus: 58.0mm
- Adjust Distance: 3.0mm
- Image Circle: ∅43.4mm
- Fluorostar 91 + Back Adapter # AD-M80-45-M48
- Back Focus: 60.0mm
- Adjust Distance: 5.0mm
- Image Circle: ∅43.4mm
- Fluorostar 120
- Back Focus: 65.7mm
- Adjust Distance: 10.7mm
- Image Circle: ∅44.4mm
- Fluorostar 132
- Back Focus: 62.7mm
- Adjust Distance: 7.7mm
- Image Circle: ∅44.4mm
- Fluorostar 156
- Back Focus: 57.6mm
- Adjust Distance: 2.6mm
- Image Circle: ∅44.4mm
Specifications:
- Lens Type: 2 Groups 2 Elements
- Length: 64.5 mm
- Telescope Thread: M92 x 1 x 6.5 mm
- T-mount Thread: M48 x 0.75 x 4 mm
- T-mount Supported: Canon EF, RF; Nikon F, Z; Sony E; Pentax K; MFT (M4/3); FUJI X
- Camera Format; > Full Frame
- Weight: 718.2 g / 1.6 lbs
Other Information
- Country of Manufacture: Taiwan
William Optics Adjustable Field Flattener 68III