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Baader full aperture 10" dob or not?

Started by nils, 06/29/2005 12:56AM
Posted 06/29/2005 12:56AM Opening Post
I expect to make a baader solar filter for my 80ED, should I also make a full aperture baader solar filter for my 10" dob? Baader seems to indicate a small off-axis mask should be made for improved contrast. Does anyone have any experience in this regard? Thank you.
Posted 06/29/2005 08:11AM #1

The sun is plenty bright enough that you don't require a large aperature to view. The off axis mask allows a smaller filter that is less likely to be damaged and is easier and cheaper to replace when it becomes necessary.

Also note that unless you have extremely good circumstances, the heat of the sun causes localized atmospheric conditions that destroy seeing. The effect of this is typically much worse than the loss of contrast due to the spider and seconday obstruction. There is little to be gained by using a full 10" aperature.

clear skies,
dan
Posted 06/29/2005 11:25AM #2
I expect to make a baader solar filter for my 80ED, should I also make a full aperture baader solar filter for my 10" dob? Baader seems to indicate a small off-axis mask should be made for improved contrast. Does anyone have any experience in this regard? Thank you.
=======

The largest possible diameter for an off-axis mask would be 95mm, not much potential for gain over your 80ED. My thinking would be to build one for the refactor and see how it goes. If you want more then go with full aperture because the off-axis is not buying you much.

jon