by Dr. Robert Berdan
October 24, 2014
On October 23, 2014 the new moon passed in front of the sun producing a partial solar eclipse that was visible from parts of North America. In Calgary, the eclipse started about 2:44 pm and finished a few minutes after 5 pm. I set up my telescope and solar filter in the backyard on a Gitzo tripod and attached my Canon 5D Mark II camera. The adapter was loose so I used good old fashion gaffer tape to secure the camera to the telescope - hey it worked! There were no clouds in the sky, but the wind was annoying and I could see the image of the sun jitter in my viewfinder. I attached an electronic cable release and used Live View to focus on a large sunspot #2192 that was near the center of the sun. I pushed the ISO speed to between 1000 and 2000 in order to get a fast shutter speed of 1\1000 of a second or better. I achieved the best results shooting in manaual mode at ISO 1000 and using a shutter speed of 1\1000 if a second. I also tried shooting in Live View mode since the mirror did not have to move out of the way.
Here is my setup, my wife Donna Berdan, makes for a better model then I do. I placed the tripod near my garage to reduce the affect of the wind and I also placed two heavy bean bags on top of the telescope in an attempt to further reduce vibrations. The focal length of the telescope is 1500 mm so even the slightest vibration is magnified.
My first few photographs of the sun were blurry, in part because of wind and slow shutter speeds which caused the telescope and camera to vibrate. Focusing on the sun is tricky so I switched the camera into Live View and zoomed in on a large sunspot. See below.
Above is a photo taken about 3:30 pm that clearly shows the large sunspot #2192. The original image is in black and white but I added the orange color with Adobe Photoshop to simulate the color of the sun. The photos below are in black in white just as they appeared in my camera viewfinder.
Below is a sequence of photos showing the moon moving from the right to the left in front of the sun over a period of about 2 hours.
My first few photos of the sun were soft and out of focus. By increasing the shutter speed and using my camera's Live View I achieved better results below.
The last vestiges of the moon clears the sun aroound 5 pm.
Unlike a full solar eclipse it did not get noticeably darker outside and I couldn't detect any drop in temperature. The one problem I had when making a short movie is that the sun would move out of the field of view every few minutes and I had to move the camera to reposition the sun every few minutes. An equatorial telescope mount would be able to follow the sun continously when properly aligned.
The most important concern when watching an eclipse is safety. Looking through a telescope or a telephoto lens directly into the sun can quickly cause permanent eye damage. You can view the eclipse safely through welders glass, a telescope with a proper solar filter attached or you can view the sun indirectly by looking at the projected image from the telescope on a piece of white paper. I used an almunized mylar filter espeiclall designed for solar viewing. Around Calgary I recommend those interested in telescopes amd solar filters to contact All Star Telescope in Didsbury.
Sunspots on October 24, photo from www.spaceweather.com - this web site shows current views of the sun daily.
The sunspot cluster 2192 poses a growing threat of an X-clsss solar flare in the coming days. Solar flares are classed as A, B, C, M or X from weakest to strongest. Each class has a peak flux of X-rays 10 times greater than the preceeding one. X class flares are major events that can cause planet-wide radio blackouts. Large flares also induce active auroras and electromagnetic storms - so I will be on the lookout for possible auoras in Calgary over the next week.
Aurora at Pontoon Lake, Yellowknife, NT taken with an 8-15 mm Canon fisheye lens at 8mm, f/4, ISO 1600 8 seconds.
I was a bit surprised by how little interest or awareness there seemed to be in the recent solar eclipse. I remember seeing my first solar eclipse in Toronto when I was a young boy. The next solar eclipse won't be visible in North America until Monday August 21, 2017 (Wikipedia). People referred to as eclipse chasers or umbraphiles will travel to remote locations to observe or witness predicted central solar eclipses - however, catching a view of a total eclipse isn't an easy task - you have to be in the right location and have clear skies. Furthermore a total eclipse may last for only 7 minutes. RB
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