Basic Solar Imaging
Most amateurs are committed to night-time astronomy and imaging, but while waiting for a clear night, which is harder to come by nowadays, imaging the Sun is fun to do and easy to set up for anyone with a webcam and a small refractor. A lot of people don't realize that there are significant resources being used at the professional level for observing the Sun's photosphere or the basic natural light view. During my visit to Mt Wilson's Solar Tower in 2003, there were still professional astronomers doing daily sunspot drawings! There are still many unkowns with respect to how sunspots work and other photospheric phenomena.

All that is needed is a webcam, small refractor and a glass solar filter. Other filters are not needed for natural light imaging. You might also consider using a focal reducer in order to get as close to a full disc of the Sun on the screen as you can. The glass filter is placed over the OTA. The other item of necessity is a solar finder! Remember you can't look directly at the Sun! The first time I tried this, it took almost an hour for me to get the Sun in the field. I was trying to judge the posiiton using shadows and the Sun's reflection on the scopes filter! Below is a very effective finder you can easily make for only $2!
Small refractors will work better obviously for a full disc image. Currently I use an Orion ED80 refractor which has a focal length of 560mm. I use a 0.6 Mogg focal reducer which threads right onto the 1.25" webcam adaptor. The refractor is piggybacked on the Cave newtonian shown here. Remember to cover all other unused optical equipment! You can see the white sheet here covering the newtonian and also the telrad finder. Mounted on the refractor is my homemade solar finder- details below! You will also have to play around with your specific optical train to see where the image reaches focus. For my set-up I have to use a 1.5" extension piece which you can see above between the webcam and the focuser in order to reach focus
This is a $2 finder you can make from a mailing tube and piece of wax paper. The tube you can buy for a couple dollars from Mail-boxes etc. or perhaps the post-office. The tube already has the plastic covers on there so you don't have to hunt around for old film cannisters or other stuff you may not have lying around. Just drill around a 1/8" hole on the 'objective end' and replace the plastic cap at the other end with a piece of wax paper. You basically have a pinhole scope that will project the dot of the sun's image onto the wax paper when it is in the field! Mount the finder with some tape or whatever you like onto your scope!
And there it is! The Sun is safely projected onto the wax paper! You are now ready to image. I found with the Toucam, best settings for imaging have been low gain, around 25% and 1/2500 sec exposure with 5fps frame setting. On good seeing days which seem to be more frequent than nights, it's amazing what you can see. Check it out! Sunspots, granulation, even faculae can be identified. Makes an excellent show for visitors!
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