In brief:
- Telescope thread: Internal thread type SCT 2"x24 UNC for Schmidt-Cassegrain telescopes
- Camera thread: M48x0.75mm / external thread 2" / filter type M48x0.75mm
- Back focus: 12 mm (standard value for Celestron or reducer)
This ring is screwed directly onto the rear thread of a Schmidt-Cassegrain telescope on one side and provides a standard M48 thread at the exit for adapting your photographic accessories. This large aperture ring is interesting for 2" photographic solutions with CMOS cameras or DSLRs with large sensors up to full frame (>=APS-C).
It avoids vignetting induced by the T2 standard and is standard on all adaptors and filters with M48 thread (filters and accessories with 2" / 50.80 mm).
List of compatible instruments (not exhaustive):
- Celestron Schmidt-Cassegrains
- Meade Schmidt-Cassegrains
- Intes Maskutov-Cassegrains
The very low height of this ring and its excellent quality make it particularly interesting for astronomers who want to "stack" a lot of accessories in front of their camera or astro camera in focus (e.g. filter wheel, correctors, adapter rings).
The adapter ring is made entirely of aluminium and is also shiny and black anodised to prevent internal reflections as much as possible.
Made in France.
Please note
For Celestron Edge-HD telescopes:
The indirect distance is only 2 mm, as the distance of the Celestron Edge-HD from the surface of the thread at the end of the telescope is calculated! According to this calculation, the ring therefore only adds 2 mm to the overall length. The "ideal" flange focal distance for Edge-HD telescopes is 146 mm and 105 mm with the 0.7x reducer for Edge-HD.
