Skip to content
All-Star Telescope is your source for all things astro from telescopes to astrophotography cameras. Have a question? We'd love to help. Email: info@all-startelescope.com Call Us: (587) 336-6621 Toll Free: 1 (866) 310-8844
Have a question? We'd love to help. Email: info@all-startelescope.com Call Us: (587) 336-6621 Toll Free: 1 (866) 310-8844

Celestron M42 Spacer Ring Kit (93618)

SKU 050234936187
Original price $60.95 - Original price $60.95
Original price
$60.95
$60.95 - $60.95
Current price $60.95

Shipping Available to Canada and USA from Edmonton Warehouse.
International shipping available by request. Contact Us

Usually ready in 24 hours

To achieve the best astroimages, it is important to attain the proper back-focus distance for your camera relative to the telescope it is being used with.

Description

If the back-focus distance your camera consumes is not exact, the performance at the corners of full frame imaging sensors will suffer—stars will appear elongated and not as pinpoints.

Example: RASA 8 with a ZWO ASI 183 MC PRO camera
Required back-focus distance for RASA 8 with included M42 camera adapter: 25mm
Back-focus consumed by ZWO ASI 183 MC PRO camera: 17.5mm
To achieve equal back-focus distance, a 7.5mm M42 spacer ring is required

Celestron’s M42 Spacer Ring kit includes three different length spacer rings to achieve the proper back-focus distance with our popular Celestron optical tubes and T-thread camera adapters.

Body

The M42 Spacer Rings are machined aluminum black anodized. The internal surfaces are blackened and glare-threaded to provide the highest contrast. Each spacer ring has a knurled surface, providing a great gripping surface for threading/unthreading. The M42 Spacer Rings are compatible with M42 x 0.75 (T-thread) camera adapters.

How to Use

Depending your method of astrophotography (DSLR or CCD/CMOS), there are two ways to use the M42 Spacer Ring. If you are using a DSLR, place the desired M42 Spacer Ring between your T-Ring and your T-Adapter for your optical tube. If you are using a CCD or CMOS camera, place the desired M42 Spacer Ring between the camera and the T-Adapter for your optical tube.

Below is a quick guide to help you determine which spacer ring to use for our EdgeHD, Schmidt-Cassegrain, and RASA 8 optical tubes:

7.5mm Provides proper spacing with RASA 8 for many ZWO cameras
12mm Provides proper spacing with RASA 8 for many Atik cameras
30mm Converts ZWO camera with filter slider to 55mm back-focus standard for use with Schmidt-Cassegrain & EdgeHD

 

Specifications

M42 x 0.75
Spacer lengths: 7.5mm (.29"), 12mm (.47"), and 30mm (1.18")
Construction: Aluminum black anodized
Interior: Blackened and glare threaded
Exterior: Knurled grip surface, each ring labeled with its length