Quote:
Originally Posted by OzEclipse
I'm picking up a number of posts including Jarrod's.
Using solar filters
As Rob pointed out solar filters are a no go on the comet. Even if Comet C/2012 S1 (ISON) reached a magnitude of -4, an ND4 solar filter drops the brightness by 10 magnitudes and and ND5 filter drops it 12.5 magnitudes. So the Sun at magnitude -26 with an ND5 filter drops down to mag -13.5 - about four times as bright as a full moon but the comet drops down to mag 8. Would you see a mag 8 comet next to a full Moon let alone something as four times as bright as a usual full moon?
However you could try using a bare piece of filter as an occulting device. This has the advantage that you can see where the sun is with respect to the edge so that the sun is unlikely to peek out and surprise you. Nonetheless extreme caution will be necessary to avoid exposure and I wouldn't try this with optical aids, just naked eye. Another possibility is to use a tall building as an occulting device. Stand just near the edge of the shadow with the comet exposed, Sun hidden.
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Joe, that is fantastic advice!
And thank you so much for such a well detailed, informative post.
I can use my solar glasses held out to block the sun out
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Or I guess if I wanted to get really serious, I could cut out a big square of solar film and mount it on a rigid cardboard frame on a long stick so my arms don't get sore.
Or a large book I'm thinking.
And perhaps even a neighbours roof top depending on the height (I don't have a tall building).