Solar prominences and sunspots in Ha
Date: March 23, 2011 3:57pm PDT
Location: Victoria, BC, Canada
This afternoon's high cloud cover wasn't conducive to observing the Sun in Ha, however it was many months since my last solar observation, so I decided to have a go anyway. The Sun had two huge prominences floating into space, with many smaller spiky prominences visible all around the edges.
Once processed with the Sobel edge detection method, the soft contrast of the original photos disappeared, revealing a surprising amount of detail. I visually observed some small sunspots, and they also survived the Sobel processing.
Equipment: Hutech-modified Canon T2i dSLR a-focal through a 2.5x Powermate, IDAS VLC filter, & Lunt LS60THa + LS50FHa solar telescope mounted on an HEQ5 tracking mount.
Exposure: 1/64 second at ISO 1600
Bandpass: <0.55 Å
Processing: ACDSee Pro 3 - Sobel edge detection; modest contrast stretch, crop.