Step-Down Adapter M67-M58Step Down Rings by Midwest Optical Systems (MidOpt) Use smaller diameter filters on lenses with larger diameter filter threads The diameter of the filter or lighting to which step down rings are coupled will be much smaller than the diameter of the lens (often resulting in vignetting) Available sizes: SD27 25. 5 SD82 77 Commonly referred to as a thread adapter Larger diameter thread is male, smaller diameter thread is female. Adapter Properties Male

SHORTPASS/NIR CUT FILTERS

74 μm Weight 170 Grams Mount C-Mount Filter Thread M37

Male Thread M34 Female Thread M37 Manufacturer Midwest Optical Systems

Male Thread M25

526 mm Exit Pupil Position -220

19 mm Entrance Pupil Position -21

4° Back Focal Length 15

Male Thread M62 Female Thread M58 Manufacturer Midwest Optical Systems

Swivellink AFSB-2XS

HF1618-12M Technical Specifications:

3 - f/22 HF75HA-1B

Larger diameter thread is male