Shooting the Sun?

[jemann]

Folks,

I'd like to be able to take shots of the Sun with my 40D and be able to make out detail like sunspots and flares.

What sort of filters should I be looking at to attenuate the suns brightness to reveal that sort of detail, as well as to protect my camera and my eyes?

[Nighthound]

If it's surface detail edge to edge you're after the Coronado line(h-alpha) of solar telescopes deliver amazing views and imaging opportunity. H-alph will resolve the best detail including flares/prominences. I'm not sure you'd get what you're after with filtration for a lens, lack of magnification would make seeing the detail you mentioned difficult to resolve with any real clarity. A 5 or 600mm would work but even if you could find h-alph filtration for the lens it would be pricey for a front unit at such an aperture. Coronado makes an h-alpha insert for 60mm standard telescopes that slips into the scope focuser. I have a Takahashi FS-60 that I'm considering getting one for.

You DO NOT want to view or photograph the Sun without proper filtration. Permanent eye damage can occur in seconds by doing so and you risk damage to your optics and camera as well.

I'm not sure about attachment of a DSLR to the Coronado line. You'd have to check out the web site. A 2" diameter focuser in the scope would be needed to use a T-Ring/T-adapter combo with your DSLR.

Here's a shot I took using the Coronado PST and a Nikon Coolpix 4300(4mgpix) camera attached to the telescope eyepiece with a Digi-T adapter system.

[jemann]

I should probably clarify that I was just intending to shoot the sun with my 100-400L and thought that I could just slap a suitable filter on the front of that and maybe a t-con on the back. Your reply suggest things are not as simple as that.

I've also been considering buying a telescope for deep sky astro shots, so perhaps I should hold off on snapping the sun until I've got some more suitable gear.

[Marnault]

Originally Posted by jemann

I've also been considering buying a telescope for deep sky astro shots, so perhaps I should hold off on snapping the sun until I've got some more suitable gear.

Solar photography can be quite a pricey hobby, the easiest would be to just photograph sunspots with a white light filter, you can buy a baader filter for $20-$60 depending on the apature. If you Google image search baader filter you will see some examples of the types of images you could get.

Now with this you won't be able to see flares or prominence which IMO are the of the most impressive things you can see on the sun. To image these you will need as mentioned above, a H-Alpha filter. Buying a separate filter for you lens would be fairly pricey, the 100-400mm F4-5.6 has an apature of about 72mm, a filter of that size would run around $1000+. And as apature goes up price goes up exponentially. I know a guy who has a 6" Daystar filter for his Schmidt Cassegrain telescope, the view is amazing but it set him back over $10,000 just for the filter.

So as mentioned the best buy is the PST by Coronado, it is a 60mm solar scope that you can pickup for around $500. You won't find anything better for solar imaging anywhere near that price.