Celestron M42 Spacer Ring Kit
- Adjusts back-focus between your camera and telescope for the best astroimaging results
- Kit includes 3 spacer rings of different lengths (7.5mm, 12mm, 30mm)
- Threads to your T-Ring and T-Adapter with standard male and female T-Threads
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. 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.
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:
| Spacer Ring Size: | Works best with: |
| 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 w/filter slider to 55mm back-focus standard for use with Schmidt-Cassegrain & EdgeHD |
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. 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.
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:
| Spacer Ring Size: | Works best with: |
| 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 w/filter slider to 55mm back-focus standard for use with Schmidt-Cassegrain & EdgeHD |
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.
At The Widescreen Centre, we prioritize prompt order processing and dispatch. We strive to dispatch all orders on the same day or the next working day, depending on the time of your order. We hold extensive stocks to ensure that your items are ready for immediate despatch. Please note that the cut-off time for same-day dispatch is usually 1:30 p.m.
For delivery within Mainland UK, we use reputable couriers to provide efficient service. You can expect your package to arrive in 1-2 working days. Please note that a signature may be required upon delivery to ensure a secure receipt.
In the case of special order items, the delivery time may be longer. If you have any concerns or questions about the delivery of your item, please don't hesitate to Contact Us. We are here to assist you.
Should there be any delay in dispatching your order, we will notify you to keep you informed.
Please be aware that The Widescreen Centre cannot be held responsible for any postal or third-party delays that may occur. We are committed to providing a reliable and efficient delivery service for our valued customers.
For more information please click here
