Tag sun

Spotty Sun an interesting target

Photonstopper
White light image of Sun. Numerous sunspots can be seen freckling the lightly-textured photosphere. At the east and west limbs of the solar disk may be seen light-colored, jagged tracks called faculae. September 22, 2023. Photo by James Guilford.

September 22, 2023. 17:12 UTC — Shooting Sun today as sunspot AR3435 rotated toward the center point of the disk, viewed from Earth. I also tried my trusty Thousand Oaks Optical Type 2+ glass solar filter on the same setup. I’ve seen some excellent results from the glass filter in the past but there seemed to be a bit of detail lost from the image. Some of the loss may have been from the filter but, perhaps more likely, there may have been a slight shift in focus or instantaneous turbulence in Earth’s atmosphere. I must say, however, while I like the brilliant color of the glass, I love the detail and tonality of the white light film — Astrozap Baader film white light solar filter.

I hope to add a telescope or system to my arsenal, allowing hydrogen-alpha (Ha) viewing and imaging of Sun’s chromosphere and prominences but I have longstanding appreciation for sunspots and hope to also dramatically improve imaging of those features.

These images are single-exposures, not stacked stills or video frames, so I shoot multiple singles aiming for momentary clarity in the atmosphere. I then manually review the frames and select the best single frame(s) for final processing. This day I used a DSLR camera with telephoto lens for the sake of convenience. The same two filters fit my 90mm refractor with a focal length of 1,000mm but using the scope would have meant significant setup; too lazy to do that, I guess.

Technical Information: Tripod-mounted Canon EOS 7D Mk. 2 camera, Canon 400mm f/5.6 L lens with Canon 2X telextender for 800mm and f/11. Mono Image: ISO 500, f/11, 1/1000 sec. Color Image: ISO 500, f/11, 1/800 sec.

The Sun, recorded within minutes of the white light photograph, this time imaged through a glass solar filter which imparted a rich orange color to the picture. September 22, 2023. Photo by James Guilford.

Cool old lens looks at hot old Sun

Photonstopper
Full disk image of Sun as it appeared at 14:45 UTC, Saturday, July 22, 2023. Color was added to make the image appear orange. Dark sunspots are scattered across the disk.

I hauled out the 1970s vintage Celestron C90 telephoto lens this morning, attached my AstroZap Baader film solar filter, and my Canon EOS 7D to quickly image Sun. I’m hoping to be able to use the compact mirror lens for quick shots such as this and for images of the Moon; trials have thus far met with mixed results. It’s a cool old lens but not as good as other gear in my current collection. The setup was mounted on a simple photographic tripod and, astro-folk will note, Sun’s orientation here is cockeyed. Once the observatory is set up and a mounted telescope put into use, we expect to see improved resolution/magnification, and won’t have to struggle with gear too heavy for the tripod! There’s a smattering of sunspots to be seen in this image along with a few other, more subtle features in the solar photosphere. Clouds rolled in soon after this image was made.