Celestron – Dauwverwarmer Ring – Aluminium Dauwpreventie – Compatibel 11' Schmidt-Cassegrain, EdgeHD, RASA Telescoop Zwart

Fantastic product! It kept my telescope dew free all through a very cold and still night of viewing. Highly recommended!

does what its suppozed to do

I bought this and installed it. The installation requires removing the existing retaining ring for the corrector plate--which has to be done with the OTA angled up. However, a paper shield comes with it to cover the glass during the "surgery." It really just involves removing about 8 small screws around the edge of the Schmidt corrector, removing the plastic ring (with the Celestron name and OTA size printed on it), aligning the dew heater ring in its place, and then using a criss-cross pattern to tighten the screws evenly (just like putting the lug-nuts on a car wheel). That's it! Takes maybe 10 or 15 minutes with a phillips head screw-driver (smaller than standard size). No technical expertise needed. Then discard the original ring or keep it for sentimental reasons. I power it with one of these: ALITOVE DC 12V 5A Power Supply Adapter Converter Transformer AC 100-240V Input with 5.5x2.5mm DC Output Jack for 5050 3528 LED Strip Module Light that I also ordered on Amazon. I was worried about the amperage and also the connector. However the unit above has way more amps than the dew heater draws and the connector is completely compatible with the dew heater ring as well as all of my other astrophotography gear--so, I have several of these inexpensive power supplies (on black Friday sale right now, 2023-11-21) for just over $10) for mount, camera, and dew heater ring.

It didn't fit my vintage Celestron C5. Had to return.

Mounting the ring is easy and only takes a few minutes. While not mandatory, it is better to purchase the Celestron Dew Heater controller than a power adapter (runs 100% all the time) to better regulate the heater. With the dew-point at 41 degrees, it took less than 10 minutes to defog an 11" EdgeHD.