The 50.4mm, unmounted Baader 3.5/4nm f/3 Ultra-High-Speed Filter Set CMOS-Optimizedfrom Baader 3.5/4nm f/3 Ultra-High-Speed Filter Set CMOS-Optimizedfeatures three precision-grade filters recommended for extremely fast optical systems from f/3.4 to f/2.3. The set includes H-alpha, O-III, and S-II filters optimized for use with CMOS sensor cameras and suitable for CCD sensors.

3-Filter Set: H-alpha, O-III, and S-II    For f/3.4 to f/2.3 Optical Systems    CMOS-Optimized and Suitable for CCDs    Reflex-Blocker / Life-Coat    Blackened Edges

3.5/4nm half width (to harmonize exposure time of H-alpha with O-III / S-II), recommended for extremely fast optical systems from f/3.4 to f/1.8

Specially designed for filter requirements of highly opened optics, such as the Celestron RASA astrograph

Enables high contrast even with the strongest light pollution to minimize the size of stars and make nebula details accessible which is useful under a Bortle 9/8/7/(6) sky

Reflex-Blocker hard-coated and optically polished, with Life-Coat sealed coating edges

Blackened edges all around, with a filter front indicator in the form of a black outer edge on the front

Optimized for CMOS sensor cameras and suitable for CCD sensors

FWHM on each filter category is carefully designed to allow for 1:1:1 exposures, matched for typical CMOS quantum efficiency and s/n ratio

Identical filter thickness to existing standards, with attention given to parfocality in the design

Related Questions and Answers

Q: 1. Does this adapter can be use on Sony a77 and Sony a99 ii for Sigma 800mm F-mount with AF? If not what adapter do you suggest to be able to use this camera with AF?

A: No, the Metabones Nikon F-Mount Lens to Sony E-Mount Camera Speed Booster ULTRA will not work with the Sony A99 or the A77: https://bhpho.to/2dRc0U1

Q: 2. Does any information show up in the viewfinder when attaching to an FS7? Such as F-Stop? Focal Length?

A: All Sigma cine lenses (except PL mount) have electronic communication for lens information to the body. This will include focal length, shooting distance and aperture.

Q: 3. Is there a version with a Cooke/I lens data port?

A: No. The lens would have to be serviced in order to do so. Sigma Burbank supports a lens conversion service that will convert passive PL mount Sigma Cine Primes to a /i PL mount. If you find yourself in need of amplifying your workflow with metadata, then the conversion service will allow that without needing to buy brand new lenses. If you’re interested in the lens conversion service or wish to know pricing then please reach out to: Sigma Burbank Service Department 213-699-0561 | serviceca@sigmaphoto.com

Q: 4. Will this lens work on the gh5 and also how do I need calculate the crop factor ?

A: The Sigma 18-35mm T2 High-Speed Zoom Lens (Canon EF) is compatible with the Panasonic Lumix GH5 Mirrorless Camera when using an EF to Micro Four Third adapter like the Metabones T Speed Booster Ultra 0.71x Adapter for Canon Full-Frame EF-Mount Lens to Micro Four Thirds-Mount Camera. This will reduce the 2x crop factor of the Micro Four Thirds sensor to a 1.29 crop factor. See the link below: https://bhpho.to/3P5irDF

Q: 5. Will IBIS (in body image stabilization) work with this adapter?

A: Yes you can use the in body stabilizer with this adapter.

Q: 6. Are these wheels compatible with Kupo High Roller Stand (14') BH #KUKS300112 MFR #KS300112?

A: The Kupo 8" Pneumatic Wheel with Square Speed Adapter (Set of 3) BH #KUKS941412 is suitable for use with the BH #KUKS300112.

Q: 7. will it vignette on red gemini 5k sensor?

A: Users have reported slight vignetting.

Q: 8. What kind of modification is needed for Summicron 50mm? Also, would this work with 2x APO Leica R teleconverter?

A: You would need to contact Leica for more information about modifications necessary to use the Summicron 50mm lens with the 2x APO Leica R teleconverter.

Q: 9. are these wheels compatible with Steadicam Stand from Tiffen?

A: No, the Kupo 8" Pneumatic Wheel with Square Speed Adapter (Set of 3) is not compatible with a Steadicam stand from Tiffen.

Q: 10. Does this adapter support autofocus on either SONY/Minolta's SSM af lenses or on the older SONY/Minolta screw drive af lenses?

A: Autofocus is not retained when using this adapter.