William Optics new AFR-IV Adjustable Flattener is designed for refractors with 500-1000mm focal-lengths.
Fully multi-coated 2-element unit using Ohara glass. The inner flattener lenses can be easily set at the optimum 66-86mm back focus (distance from flattener lens to film or CCD plane).
• Designed with APS chip-size DSLR cameras in mind.
• FMC doublet design.
• Produced entirely with Ohara optical glass.
• Flattens the field remarkably well for nice round stars!
• Will work with WO 500-1000mm focal length refractors.
• William Optics polished anodized finish.
• All internal surfaces threaded and blackened for no reflections.
Easy to Use
• Rotating T-ring thread for easy connection to DSLR cameras. The T-ring adapter is provided with a lock screw and extra lock retaining screws.
• Will accept any standard T-ring.
• Inserts directly into 2" focuser.
Fully multicoated optics
Lens-to-chip distance : 66-86mm
Power : 0.75x ~ 0.8x
Rotating T-ring adapter
Clear Aperture : 50mm
L 84mm : W 77mm : H 123mm
Weight : 540 g