Sunspots

[jimhines]

I was testing the solar filter for the camera, in preparation for Monday’s eclipse. We won’t be seeing the total eclipse, but I’m hoping to get some good shots of the partial.

As I was processing the results, I realized I’d captured sunspots!  (Those dark spots in the upper left.)

Click to embiggen.

For those who wonder about such things, this was taken on the 100-400mm lens, fully zoomed to 400mm. ISO 640, f/10, with a 1/3200 shutter speed. I had to set everything manually, because the camera overexposed the shot if left to its own devices.

I think next time I’ll try to reduce the ISO down to about 100 and see if that gets rid of the minor graininess.

Processing involved cropping the shot, noise reduction, and an orange overlay.

Mirrored from Jim C. Hines.

Comments

[asakiyume]

very cool!

[beccastareyes]

Those are on the leading side of the Sun, so we're hoping they will rotate into clear view for Monday. Glasses probably won't pick them up, but the university I work for will have sunspotters (basically a couple lenses that project a magnified Sun on a screen without a riks of people lookign through the scope as in a traditional telescope) out.

[jimhines]

Oh cool! Thanks for that!

[thewayne]

What uni are you at? My wife operates the 3.5 meter at Apache Point Observatory and also operates the Apollo lunar laser ranging program. They're just coming out of summer shutdown right now, I'm planning on helping out at the National Solar Observatory for Monday.

[beccastareyes]

The University of Nebraska at Lincoln. I do mostly space-based things (with the Cassini mission's data), so the only time I am at the telescope are public nights.

[thewayne]

Neat! It didn't occur to me to look in to picking up a filter for my camera, idiot I, but I'm also trying to be kinda frugal with money right now until I can whack another couple hundred $$$ off our monthly outflow. Last night my wife reminded me that forest foliage can act as pinholes, so weather permitting (which isn't promising, sadly) I may do some time lapse photography with my two cameras as I bought a second timer.

Also, birds and other animals freak during solar eclipses. Sound recording in a forest might be interesting, maybe I'll use my Lumix to record video to give me an audio recording.

Yeah, you can probably dial down to ISO 100 no problem. The sun is kinda bright. :-) It's also inherently grainy, so don't be surprised if you don't get a smooth result.

Something you might want to acquire and try. First, the acquisition: an intervalometer. I bought a used Canon timer for my 6D and it's wonderful for some things, and, as mentioned above, bought a second timer so I can have both of my bodies shooting simultaneously. It opens up a world of things that you can experiment with. Second, there are web sites that will tell you when the International Space Station is transiting the sun. With a timer, you can do multiple exposures of the ISS transit, then composite them in Photoshop and get a cool series of dots of the space station across the sun....

I have a photograph and video where I caught the ISS during a night photography experiment with such a timer that I'm VERY happy about. The ISS streaks across the video about 8 seconds in from top just right of center to lower left.

https://thewayne.dreamwidth.org/1016098.html

[jimhines]

Nice! There are also smartphone apps for finding the ISS :-)

This is my favorite shot of it, from the Launch Pad workshop last year: https://www.flickr.com/photos/41225422@N00/27556586646/in/album-72157669092163011/