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The Sun

 

It is extremely dangerous to look directly at the Sun, with or without optical aid. Great precautions must be taken when attempting to observe the Sun.

I use a 5-inch diameter filter that I had purchased for a previous smaller telescope. I mounted it on the front of my 10 inch Newtonian by using some cardboard and black tape (all gaps had to be completely sealed). It cuts down the light by a factor of 100,000 (nearly 17 photographic stops) and gives a pink tinge.

 

 2011 Oct 18- the Sun

A very showery day and I was lucky to get any view through thin cloud. The complete view through thin cloud is not worth showing. With a bit of processing I was able to get a cropped piece to make a daily comparison:

 

 2011 Oct 17 - the Sun

A showery day and I was lucky to get any gaps in the cloud.

Canon EOS 5D MkII ISO1600 1/200s 254mm Newtonian (2x Barlow, f=2400mm)
Aperture restricted to 100mm by 16.5-stop filter -> f/100 2011 Oct 17 13:56:04 UT

 

 2011 Oct 16 - the Sun

Through gaps in the clouds today. I was interested to see how yesterday's sunspot groups had developed in 24 hours.

Canon EOS 5D MkII ISO1600 1/200s 254mm Newtonian (2x Barlow, f=2400mm)
Aperture restricted to 100mm by 16.5-stop filter -> f/100 2011 Oct 16 12:15:21 UT

 

 2011 Oct 15 - the Sun

Canon EOS 5D MkII ISO400 1/60s 254mm Newtonian (2x Barlow, f=2400mm)
Aperture restricted to 100mm by 16.5-stop filter -> f/100 2011 Oct 15 13:19:30 UT

 

 2011 Sep 8 - the Sun

There have been no clear nights here since twilight should have made observing possible again in mid August. So instead I have photographed the Sun in gaps between the daytime clouds.

Canon EOS5DMkII 254mm Newtonian stoppped to 125mm @ 1200mm f/9.6 1/500s ISO400 2011-09-08 14:57:52 UT
From Rookhope 54.8N 2.1W 330m asl. Rural, almost no light pollution (3 Bortles)

The camera was at prime focus for this view of the whole Sun. I used a 5-inch diameter filter that I had purchased for a previous smaller telescope. I mounted it on the front of my 10 inch Newtonian by using some cardboard and black tape (all gaps had to be sealed). It cuts down the light by a factor of 100,000 (nearly 17 photographic stops) and gives a pink tinge.

I then used a 2 inch Barlow lens (x2) to get closer views of the 3 groups of spots currently visible:

Canon EOS5DMkII 254mm Newtonian stoppped to 125mm @ 2400mm f/19.2 1/100s ISO400 2011-09-08 15:06:33 UT
From Rookhope 54.8N 2.1W 330m asl. Rural, almost no light pollution (3 Bortles)

Canon EOS5DMkII 254mm Newtonian stoppped to 125mm @ 2400mm f/19.2 1/100s ISO400 2011-09-08 15:06:16 UT
From Rookhope 54.8N 2.1W 330m asl. Rural, almost no light pollution (3 Bortles)

Canon EOS5DMkII 254mm Newtonian stoppped to 125mm @ 2400mm f/19.2 1/100s ISO400 2011-09-08 15:06:33 UT
From Rookhope 54.8N 2.1W 330m asl. Rural, almost no light pollution (3 Bortles)