M48 Extension 37mm
This M48 adapter/extension can be screwed into a M48 camera adapter as if it was a 2" nosepiece, so that you'll be able to use it in a 2" eyepiece holder.
It will give you the necessary increased aperture when imaging with a full frame camera.
Compatible with the following Skywatcher adapters 20238 Nikon M48 Camera Adapter and 20237 Canon M48 Camera Adapter
Application: Celestron Edge HD with focal reducer, OAG and dSLR camera
One of our customer was looking for a solution to connect his dSLR camera via an OAG (Off Axis Guider) with his Celestron Edge HD telescope whilst also having a focal reducer in the optical path.
Celestron's own OAG (Off Axis Guider) would work fine when used without a focal reducer, but the introduced focal reducer causes a problem as the achievable back focus from the focal reducer to the camera sensor is 105mm.
To achieve this we would need a comparatively short adapter to convert from the SC thread into M48.
Model 2956220 offers a 47mm back focus that is just what wee needed.
So here is the recipe:
Celestron Edge HD
Celestron Focal Reducer 0.7X for Edge HD (model 94240 or 94241 or 94242)
2956220 2" ClickLock CL-SC Eyepiece Clamp for SC Telescopes (optical length = 47mm) (THIS PRODUCT)
M48M4837 Lacerta M48 Extension with 37mm length (optical length = 0mm)
OAGhu48 Lacerta OAG (Off Axis Guider) (optical length = 11mm)
dSLR camera (various optical length, i.e Canon dLSR cameras have 44mm depth)
As you can see, the total optical length (based a Canon camera) is 102mm; the missing 3mm can be achived by moving out the M48M4837 extension from the ClickLock clamp by 3mm, thus achieving the perfect back focus distance.