ATM spectrohelioscope (was bounced ...)

[Suzanne Sarlette/Gerald Pearson <suegerry@mut1.muscanet.com>]

Chris,

> >
> >The solar scope build & run by the Rockford Astronomy Club (Rockford,
> >Illinois, USA) _can_ be run in spectrohelioscope mode, but I understand
> >that it very seldom is.
> 
> Any idea why ... no interest or is there not that much to see on the
> spectrohelioscope?

I'm not sure, but my guess is that it might be a pain in the butt to
switch over from normal projection (or spectroscopy) to
spectrohelioscope and back again.  And anything that requires an extra
half hour or hour is -- in practice -- going to be avoided.

I would think that a spectrohelioscope would be a neat thing to have.  I
think it would be roughly equivalent to having about a dozen different
Daystar interference filters which you can swap into your scope as
desired.  Not only can you select the H alpha line to watch stuff, but
there are _other_ wavelengths that show _other_ features.  I'm not
familiar with the details, but I do know that one of the calcium lines
brings out features which are not apparent in either H alpha or white
light.  I would expect that even playing around with the H alpha
bandwidth would allow you to fish out features which might be difficult
or impossible to detect with a given Daystar interference filter.

        -- Gerry