Making of Solar Filter from Baader AstroSolar Film

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In my previous post, I mentioned my reasons for ordering the Baader AstroSolar film in preparation for photographing the transit of Venus. In this post, I will describe the process that I adopted for making a solar filter. The filter can be fitted to any D-SLR lens using a standard Z-PRO Cokin ND filter holder. My design choice was primarily dictated by the fact that I will be using my D-SLR with a telephoto zoom lens (most likely my Canon EF 70-300mm f/4.5-5.6 IS USM) instead of a telescope, and I already have the Z-PRO filter holder. The Baader film came with instructions on how to construct a Filter Cell for using any telescope; you could also follow their instructions to construct your own filter. I don’t think, from an image quality standpoint, that there is any fundamental difference between the two ways of mounting the filter in front of your lens. Their recommended way is suitable if you are using a telescope, or you don’t have a filter holder like one mentioned here.

The picture below shows all the material that you may need (I actually ended up using a blade too and didn’t use the gloves at all) to construct the filter. I was extra careful not to touch any part of the film with my figures. Things to note in the picture are two 4×6 size photo mat that I bought from Michaels, the AstroSolar film (unrolled slightly), and the Z-PRO Cokin filter holder on the top right.

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Let’s photograph the transit of Venus

On June 5, (or June 6, depending on your Geo-location) the lovely and beautiful Venus will pop up in-between the Earth and the Sun, eclipsing a tiny portion (1/32 the size of the solar disk) of the Sun. The rarest of all eclipses, known as the “Transit of Venus,” last happened in 2004. So, you may think — why is it labeled “rare,” as it is repeating after only 8 years (not so significant compared to the average human life-span)? Well, it is predicted that the next transit will only happen again in December 2117 which is about 105 years from now, making this transit of Venus the last one of this century. As it turns out, this rare celestial event is also one of the most accurately predictable one! The transits happen in pairs which are separated by 8 years and the pattern of paired-transit itself repeats every 243 years.

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Gearing up: Received Baader AstroSolar film

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The last time I pointed my camera towards the Sun to photograph the 2009 Total Solar Eclipse, which is also a “once in a lifetime experience,” I had used a piece of a $9.00 Mylar Thermal Blanket instead of a proper solar filter in front of my lens. Well, that was not by choice but by chance as I was carrying a Mylar thermal blanket with me. Mylar blankets, which are made by vacuum depositing a very precise amount of pure aluminum vapor onto a very thin film substrate (Mylar), reflects upto 97% of radiated heat. This makes them very effective for preventing body heat from escaping. They are commonly used by campers as “thermal blankets” and also used in a lot of solar projects.

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An experience of a lifetime: Witnessing the longest Solar Eclipse of 21st Century

I consider myself very lucky to have witnessed the longest Solar Eclipse of the 21st century on July 22, 2009, which I saw from Varanasi, India. Scientists have predicated that such an event is not going to repeat until June 2132. I was reminded of my experience of that amazing celestial event, when I once again observed an annular solar eclipse the day before yesterday during sunset, which was partially visible from Dallas, Texas. The following post is an account of my experiences of the solar eclipse in 2009.

Coincidentally, I was already in India during that time, so I decided to travel to Varanasi, which is one of the oldest cities in the world, to observe the eclipse. The magnificent show of nature, lasted for 6 minutes 38 seconds in places which coincided with the point of maximum eclipse. The eclipse was visible from a narrow corridor through northern Maldives, northern India, eastern Nepal, northern Bangladesh, Bhutan, central China, and the Pacific Ocean, including the Ryukyu Islands, Marshall Islands and Kiribati.

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Extended corona — The corona (or crown) is directly visible only during totality.

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Inner corona and Prominence (the bright red loop).

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The Diamond ring (C3) — At third contact (C3) the brilliant diamond ring marks the end of totality.

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Partial Eclipse- Sometime after the first contact (C1).

(Continue to read more about the event, some more photographs and about solar eclipse photography)
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Weekly Photo Challenge: Blue

"Engulfed in blue"

Cloud engulfed in blues

Humans have covered the face of the earth with deep concrete forests in the name of modernization and advancement. Once there used to be green trees everywhere I looked below while floating miles and miles across the great plains, mountains, and rivers. Nature used mostly organic forms on structures and engravings on the surface of the earth — very similar to my own form (when I have one!), and I felt happy as I could relate their shape to my own. Now I see regular geometric patterns — circles, triangles, squares, rectangles, trapezoids everywhere I look. I feel sad; I feel lost; I feel lonely. I don’t seem to belong here. I feel blue!