This 1.25" eyepiece round Baader 6.5nm S-II Highspeed CMOS Filter 1.25"from Baader 6.5nm S-II Highspeed CMOS Filter 1.25"is recommended for extremely fast optical systems from f/3.4 to 1.8, and is designed for the special filter requirements of fast optics like Celestron RASA astrographs. The filter features a Reflex-Blocker hard coating, which has been planoptically polished, and has Life-Coat sealed edges. It is equally suitable for modern CMOS sensors as well as for older CCD camera technologies.

Optimized for CMOS, Suitable for CCD    Reflex-Blocker Hard Coated    Life-Coat Sealed Coating Edges

• 6.5nm FWHM, recommended for extremely fast optical systems from f/3.4 to 1.8
• Specially designed for the special filter requirements when used with fast optics like the Celestron RASA astrographs
• Reflex-Blocker hard coated and planoptically polished with sealed coating edges (Life-Coat)
• Blackened edges all around, with filter-lead-side indicator in the form of a black frontside outer rim
• Optimized for modern CMOS cameras, but excellent for CCD camera technologies

Related Questions and Answers

Q: 1. Would this work on a full-frame 35mm lens?

A: Yes, the SIRUI 1.25x Anamorphic Adapter is designed to turn any spherical lens into an anamorphic or increase the squeeze ratio of anamorphic lenses.

Q: 2. How well would this adapter work on gfx sensor cameras? Any strong vignette or something?

A: The Sirui 1.25x Anamorphic Adapter will work on GFX sensors.

Q: 3. I'm a beginner so plse forgive this question - but how do these filters attach to the eyepieces? I see the filters have femal;e threads on them - do they screw onto the top of the eyepiece? Does this mean all eyepieces have male threads so that they accept filters suich as these to be attached? Thanhs, just trying to understand how these work

A: The Celestron Moon Filter Set has male and female threads. . The easiest way to attach a filter is on the diagonal. This way the eyepieces can be changed without re-attaching the filter from one eyepiece to another. Female thread on a filter is used for stacking several filters.

Q: 4. Can you please list out the items come with this package $657.00 : 2.6X glasspath compensator and 2 inch nosepiece?

A: In the Box Alpine Astronomical Baader MaxBright II Binoviewer (1.25") Carrying Case Zeiss Micro-Bayonet Mounting Adapter Limited 2-Year Warranty Alpine Astronomical Glasspath Corrector 2.6x for Maxbright/Mark V Binoviewers BH #ALGLASS3 • MFR #GLASS-3 https://www.bhphotovideo.com/c/product/1405373-REG/alpine_astronomical_glass_3_glasspath_corrector_1_2_6_for.html Alpine Astronomical Baader 2" T-2 Nosepiece BH #ALT216 • MFR #T2-16 https://www.bhphotovideo.com/c/product/1406318-REG/alpine_astronomical_t2_16_baader_2_nosepiece.html

Q: 5. It looks like the ASFT 100 and the ASSF 80 will both fit my telescope. The Baader film is the same in both filters. What am I getting in the ASFT 100 that warrants spending the extra $10?

A: A larger metal ring. A larger film area.

Q: 6. Is it 7mm or 10mm optical length?

A: Optical Path Length: 0.35-0.94" / 9.0-24.0 mm.

Q: 7. Does this come apart into two pieces like the Orion so you can put one half on the eyepiece and the other on the diagonal?

A: No, it dose not come apart.

Q: 8. Will this filter work with the Celestron Astromaster 130?

A: Yes, the AstroMaster 130EQ uses 1.25" eyepieces, so the 1.25" Oxygen III Narrowband filter will work.

Q: 9. What is the smallest filter size recommended? Is a 62mm filter size lens on MFT too small for good results?

A: With the Sirui 1.25x Anamorphic Adapter, a filter smaller than the front filter thread size of 82mm is not recommended.

Q: 10. Why are there two Herschel wedges, photo and visual?? why can't one wedge be used for both with some adjustments?

A: The Alpine Astronomical Baader Cool-Ceramic Safety Herschel Solar Photographic Prism Mark II includes all the items in the visual version with the addition of 1.8, 0.9, and 0.6 neutral density filters. Aside for the extra filters, the other components are exactly the same.