William Optics Adjustable Field Flattener 68III

Product Details

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, 110, 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, FLT110, FLT120, FLT132, GT102 (with 3" focuser) and many others refractors with focuser M92x1.0 thread.

Compatibility:

• Gran Turismo 81 + Back Adapter # WO-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 # WO-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