Eclispe Filter

[vandy]

I have been looking at the pictures of the solar eclispe on the internet and notice that there is a note that the pics have been taken with a special filter. Does anyone know what kind of filter?

vandy

[fx101]

To take photograph a solar eclipse, you need a metal infused glass filter or a polymer filter. I have two for my 300mm f/2.8. I bought both from this site one cost me $52 (it was 52mm) for the threaded black polymer filter. The advantages of black polymer is that it reduces light immensely, is not reflective, and is very strong. The issue is that you won't get the best image quality. Granted, the image you will get is decent, but if you are using a supertelephoto lens (or rent one for the day) your images aren't necessarily going to be GREAT. Because of this, I bought a Type II glass filter (around $100) and cut and ground it into a square shape that would fit my Cokin filter holder. The distance between camera and filter with a reflective glass type II filter is essential for proper photography. You couldn't use a threadable glass solar filter because the distance between lens and filter would be WAY too small and you would have internal reflections occur. Even when using the filter on the cokin mount, I ALWAYS mount a polariser underneath it (the cokin polariser). This prevents light from reflecting off the lens, back to the filter, and back to the lens. Internal reflections are blocked by the polariser.

Once you have mounted either the glass type II filter or the black polymer filter, you will need to calculate exposure. You can now view through the viewfinder since the filter darkens the sun quite a bit and blocks the UV light. It's perfectly safe to look through. The issue in calculating exposure is that your camera sees savage contrast differences between the rays of sunlight and the very dark sky. It will compromise (usually) and overexpose the sun and underexpose the sky. You want to use spot metering on the visible parts of the sun so that it exposes correctly. The sky, be default, will be dark.