Celestron Origin Performance in Canadian Winter Temperatures

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Although Celestron has not included an operating outdoor temperature range in their specifications data, they have recommended -5°C to 40°C in their online FAQ section. For users located in northern (or southern) climates where winter temperatures are often lower than -5°C, this could be an important issue affecting purchasing decisions. It is also important to note that Celestron has not stated what the adverse effects of cold temperatures might be on Origin's optical, electrical, and mechanical systems.

As a retired scientist, I decided to make this low temperature limitation a research project for the 2024-25 winter, just about to officially end this week (20 March 2025). This was a risk I took in order to provide Celestron useful feedback for this amazing technology. The sections that follow are arranged in order of decreasing temperatures.

Dennis F. Jones

Retired Physicist

Fellow of the Acoustical Society of America since 2000

National Member of the Royal Astronomical Society of Canada

This image, centred on 73 Orionis (HD 43247), was taken during an overnight session that started at 7:51 pm on October 28, 2024 and ended at 7:07 am the following day. The outdoor temperature at the time of this capture was -1°C. Origin performed normally throughout the 11 hour session.

This image of Comet C 2023 A3 (Tsuchinshan-ATLAS), centred on HD 184364, was taken at 5:47 pm on December 23, 2024. The session started at 5:35 pm and ended at 7:20 pm with an outdoor temperature -8°C. Origin performed normally throughout the session of about 2 hours.

This image of open cluster NGC 1746 in Taurus was taken at 8:18 pm on one of the first chilly nights in the fall - November 27, 2024. The session started at 7:24 pm and ended at 8:58 pm due to cloud cover. The outdoor temperature was 3°C. Red dots/streak were observed in the image shown by the arrow. I didn't notice this at first but when I did, I sent Celestron Tech Support the image and they explained to me it was a hot pixel. The cause of hot pixels is found in the FAQ sheet on their website. I quote

"If you notice some red “hot pixels” or other image artifacts, we recommend using “Recapture Dark Frames” in Menu>Settings>Advanced. The dark frames stored on Origin were taken at the factory and may not perfectly match your current observing conditions (i.e. temperature). Capturing the dark frames in the same conditions you are imaging will better eliminate any residual hot pixels or artifacts. NOTE: Be sure to install the dust cover on Origin before recapturing dark frames, we also recommend doing this outside at night, or in a dark room, and covering the entire optical tube with a towel or blanket to block any stray light."

I decided not to recapture dark frames for several reasons: (1) I do not want to adversely affect my long term studies (ex. variables) by changing any of Origin's factory settings, (2) What if I make a mess that is far worse?, and (3) I want to see if these hot pixels will self-repair once the warmer summer nights return.

Furthermore, if I did recapture dark frames, what temperature do I use? It's Spring this week and the cold temperatures of winter are over (hopefully). Also, is this problem going to keep recurring every winter?

In the following section(s) I am going to post a consistent capture of a star field I can see year round to monitor changes in the hot pixels/streaks. I have chosen 5 Ursae Minoris with 10-sec exposures, 10-minute total integration time, no filter, and no post-processing.

This image centred on 5 Ursae Minoris was taken at 8:14 pm on March 19, 2025. The session started at 8:10 pm. The outdoor temperature was 7°C. Red dots/streak have disappeared.