Lunar Eclipse 2018
I went off just outside Mather airport and started to set my telescope up. Unfortunately I didn’t have both of my telescopes with me so I couldn’t broadcast live. With me I had my William Optics Megrez 72 APO.
The night was very humid, cold but there wasn’t any wind at all. As the eclipse was progressing the moon was turning more and more red/orange.
- ISO-100 and 200 with Canon EOS 50D
- Exposure Time: See each image for details
- Telescope: William Optics Megrez 72mm f/6 Doublet Apo Refractor
- Mount: Sky Watcher EQ6 Pro
- Date/Time: 1/31/2018, 3:03 to 5:42 AM (PST)
- File Format: RAW (CR2)
- Weather Conditions: Cloud Cover from 40% to 10%, Transparency below average, seeing average 3/5, darkness 4.4 for 0.2 hours and magnitude 4.3 at full eclipse.
- Wind: 6 to 11 mph (Forecast), 0 to 5 mph (Actual)
- Humidity: 85% to 90%
- Temperature: 41° to 50° F (5° to 10° C)
The humidity was the major disrupting factor this night. I had to bring in both telescope and camera twice and put the car heater on to get rid the moisture that was on the lenses causing the images to get worse over time. Unfortunately my telescopes are not equipped with a dew heater so over time they accumulate condensation from the surrounding air.
Despite that set back the night was remarkably beautiful and quiet. Only the airfield lights and street lights kept shining in the distant background. A few curious bypassing cars stopped to see what I was doing in the darkness and took the chance to look at the spectacle themselves. I must say they were very considerate and turned off their beams to not blind me which I appreciated lots. Thank you!
The results are presented below,
To work with lunar eclipse exposure times you can use the following formula in your preparations:
- t = exposure time
- f = focal ratio
- Q = lunar brightness value
- I = ISO #
If you don’t know the focal ratio of your telescope/camera lens you can find that out by calculating f = focal length / aperture. Lunar brightness can be determined through the Danjon scale. More information on exposures and lunar brightness visit Mr Eclipse website here. Fred Espenak’s table breaks it down very straight forward and simple right here.