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A quick spectrum test.
Put a dvd disk shiny side up on a table and have the room light on.
Move about at a distance of an arm length until you can see one or two red stripes going from centre to edge.
Works well with light shining from behind over shoulder. Can do outside using sun.
Bring filter up to eye. If the line changes to a spot, then narrow band filter. If the line looks much the same then coloured glass.
If coloured glass then could be similar to R25 photographic filter or one of the Schott RG6xx. May or not pass IR, the Schott glass which you can see through does.
Another test is to check with 630nm laser pointer, but most are 650nm. A true H-alpha filter will block most of the 630nm light.
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