One of the most interesting and my all-time favorite celestial objects is the Sun. Many star-gazers somehow miss this quite average star which is the closest star to us and the only one that we can observe in such detail. It is also one of the few celestial objects that you can observe during the day. This is one of my first pictures of the Sun:
The very first thing that you hear about solar observation is safety. As everybody already knows you can't look directly at the Sun with your naked eyes. However, as it turns out, most makeshift solar filters such as mylar, dark or smoked glass, exposed film, etc. do not offer the adequate protection from UV (Ultraviolet Rays) that can cause permanent eye damage. Do not use them! It is very important to use a properly graded astronomical filter before attempting any kind of solar observation. There are many types – just make sure you get something that is rated 'safe for astronomical use'.
The type of filter that I use is Baader Astro Solar Filter (ND-5 rated). It replaces the cap at the end of the scope tube and blocks 99.999% of all sunlight. This type of filter is easy to use and is probably the safest. However, the filter that I got despite being made the same manufacturer as the telescope (Celestron) doesn't securely lock into place. I always use masking tape to secure it just in case. A gust of wind could easily rip it of and the Sun can blind you in a splint second.
There are also filters that attach to the eyepieces by they are known to crack and will not protect your telescope. Depending on the aperture of your telescope you may actually have heat build-up inside the tube that will literally melt your instrument.
Pointing telescope at the Sun is tricky and requires some practice (remember, you can't look through the viewfinder). The method commonly used is moving the tube until you minimize it's shadow on the ground. When you achieve this the telescope will be in alignment with the Sun.
I personally think that solar observation is 'a must' for any beginner astronomer. I actually regret not trying out my telescope during the day at first. When you get your instrument out of the box for the first time it makes it A LOT easier to learn it in daylight. Everything from setup, configuration and focusing is easier with the Sun over your head. It took me about 15 minutes just to focus the telescope the first time I got it out. As it turns out, focusing on stars is a lot more difficult than I originally thought!
Pointing your telescope to a distant object in daylight allows you to practice focusing and using your scope as well as it allows you to notice any problems which are a lot more difficult to spot at night.
Labels: astronomy, astrophotography, photography, solar, sun