Lunar Eclipse April 4, 2015
Update September 27, 2015 - See tonight's "supermoon" total eclipse tonight! Moon rise occurs just before sunset on the West Coast, the moon will be fully eclipsed 7:11 - 8:23 pm. For eclipse phase timing in your area, see the article at www.timeanddate.com/eclipse/lunar/2015-september-28
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Notes from the April 5, 2015 lunar eclipse:
Lunar eclipses are a fun challenge, in part because they push the limits of your equipment. This shot was taken at 4:51 am yesterday, about 6-7 minutes before totality, so there was a sliver of bright sunlight on the moon.
The Canon EF 70-200 f/4 IS lens was well focused, but shooting any lens at it's maximum aperture tends to result in slightly less sharp images. Adding more glass elements such as the 2X teleconverter further challenges sharpness. Adding a teleconverter also reduces the f-stop, in this case 2X to f/8. I wanted to stay at or below below 1 second exposure time to reduce motion blur, and at ISO 1600 I could use 0.6 second. The high ISO also creates a little bit of noise, which can also challenge fine detail.
I had changed my shooting location when the weather forecast made the original ones I had identified look less attractive with below freezing temperatures, high winds, and possible clouds to obscure the eclipse. I decided to just catch what i could from home. I was shooting a time-lapse sequence, and shooting at 400mm I had room to lengthen the exposure time as the moon darkened, but and the moon set just before totality.
I had my Canon 70D with a Canon EF 70-300mm f/4-5.6 lens on a star-tracking mount to capture a time-lapse of the eclipse progress without the moon moving out of the field of view. at 300mm the effective focal length was 480mm, but shooting wide open at f/5.6 that lens was a little softer than the EF 70-200mm and 2X teleconverter combo, even with the moon's relative motion taken out of the equation.
I was basically using the 5D Mark III to measure and track exposure as the eclipse progressed and the moon illumination constantly changed.
The 70D / 70-300mm combo is a lot lighter than the 5Dmkiii / 70-200mm / 2X combo. Heavier camera bodies and longer, heavier lenses can sometimes cause various problems with sky tracking mounts, but it may be worthwhile to test the 5Dmkiii /70-200mm / 2X setup on the sky tracker and backing off of the maximum aperture and a stop or two on the ISO to get more sharpness and less noise, lengthening the exposure time.
It's tough to perform relevant tests since lunar eclipses come so infrequently and I hate to effectively "waste" them with testing, but I could add filters to cut enough light to simulate an eclipse, so when an eclipses do arrive I've already determined the subtle impact of each decision: specific lens choice, opening the aperture all the way, using a teleconverter or not, various ISO settings, various exposure times with and without the sky tracker, exposure time vs. sky tracker motor vibration, and so on.
Lunar Eclipse April 4, 2015
Update September 27, 2015 - See tonight's "supermoon" total eclipse tonight! Moon rise occurs just before sunset on the West Coast, the moon will be fully eclipsed 7:11 - 8:23 pm. For eclipse phase timing in your area, see the article at www.timeanddate.com/eclipse/lunar/2015-september-28
---
Notes from the April 5, 2015 lunar eclipse:
Lunar eclipses are a fun challenge, in part because they push the limits of your equipment. This shot was taken at 4:51 am yesterday, about 6-7 minutes before totality, so there was a sliver of bright sunlight on the moon.
The Canon EF 70-200 f/4 IS lens was well focused, but shooting any lens at it's maximum aperture tends to result in slightly less sharp images. Adding more glass elements such as the 2X teleconverter further challenges sharpness. Adding a teleconverter also reduces the f-stop, in this case 2X to f/8. I wanted to stay at or below below 1 second exposure time to reduce motion blur, and at ISO 1600 I could use 0.6 second. The high ISO also creates a little bit of noise, which can also challenge fine detail.
I had changed my shooting location when the weather forecast made the original ones I had identified look less attractive with below freezing temperatures, high winds, and possible clouds to obscure the eclipse. I decided to just catch what i could from home. I was shooting a time-lapse sequence, and shooting at 400mm I had room to lengthen the exposure time as the moon darkened, but and the moon set just before totality.
I had my Canon 70D with a Canon EF 70-300mm f/4-5.6 lens on a star-tracking mount to capture a time-lapse of the eclipse progress without the moon moving out of the field of view. at 300mm the effective focal length was 480mm, but shooting wide open at f/5.6 that lens was a little softer than the EF 70-200mm and 2X teleconverter combo, even with the moon's relative motion taken out of the equation.
I was basically using the 5D Mark III to measure and track exposure as the eclipse progressed and the moon illumination constantly changed.
The 70D / 70-300mm combo is a lot lighter than the 5Dmkiii / 70-200mm / 2X combo. Heavier camera bodies and longer, heavier lenses can sometimes cause various problems with sky tracking mounts, but it may be worthwhile to test the 5Dmkiii /70-200mm / 2X setup on the sky tracker and backing off of the maximum aperture and a stop or two on the ISO to get more sharpness and less noise, lengthening the exposure time.
It's tough to perform relevant tests since lunar eclipses come so infrequently and I hate to effectively "waste" them with testing, but I could add filters to cut enough light to simulate an eclipse, so when an eclipses do arrive I've already determined the subtle impact of each decision: specific lens choice, opening the aperture all the way, using a teleconverter or not, various ISO settings, various exposure times with and without the sky tracker, exposure time vs. sky tracker motor vibration, and so on.