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Old 15-12-2020, 11:39 AM
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Merlin66 (Ken)
Spectroscopy Wizard

Merlin66 is offline
Join Date: Oct 2005
Location: St Leonards, Vic
Posts: 8,430
Spectroheliograph focus???

Just a hint to new SHG users.....
How do you know if your slit gap is at the focus of the telescope?
Normal method is to check the top/ bottom edges of the solar spectrum being recorded. When in focus, they should appear tight and crisp.
A quick way to get you close....
Use a finder to look through the objective and check that the slit gap appears in clean focus.
Helps during initial set-up.
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