Recently, my astronomy club received a very special solar telescope that allows us to view and photograph the sun (safely) in a way that most people never see.

The images here are some examples of the details that this "hydrogen alpha" telescope allows us to capture. Here you can see the mottling of the sun's surface, called spicules as well as the prominences along the edge of the disk. Many confuse these with solar flares. But, while promineces take shape and evolve over a matter of hours or even days, solar flares are much more energetic and happen over a much shorter time span. The dark worm-like "filaments" can also be see on the sun's surface, which are actually just prominences as seen from an overhead perspective.

The method of capturing these images is a bit different than that of imaging nebulae, galaxies and other dimmer "deep-sky" objects. Whereas with deep-sky images, a number of long exposures are taken and stacked to create a composite still image comprising hours of exposure, solar, lunar and planetary photography is done by taking video of the object. Since these are brighter objects that do not need long exposures to capture, we want to capture them in as close to real time as possible and try to negate the effects of having to look through Earth's atmosphere. This is done by taking many short images, or frames, in a video. These frames are then fed into a piece of software that grades them for clarity and sharpness and selects a percentage of best frames and throws the rest out. These best frames are then aligned and stacked to further eliminate noise and seeing conditions and composited into a still image. The stills are further processed to enhance the detail and in this case, falsely color the image to make the coloration look more like what the eye sees. The camera used is actually monochrome which captures greater detail than a color camera with a bayer filter in front of the sensor. The sensors in these cameras also tend to be smaller so that greater frame rates can be used. The full disk image at the top is actually a mosaic of four images which were stitched together with Photoshop. The others show the actual field of view of this scope/camera combination. It can almost, but not quite fit the whole disk.

This time of year is terribly frustrating because the sun is setting so early that I can't get out to the observatory on days that I work which relegates me to only doing solar imaging on the weekends. And, this fall has so far been the pits, at least on Saturdays and Sundays. I have not been able to do any captures since before Thanksgiving, but it looks like this weekend might offer some clear skies. Here's hoping...