In article ,
writes:
Amateur solar flare imaging is on my list of
things to do.

If you are talking about white light imaging, aren't such flares
rare?

The problem becomes how to size
and control a sun cover disk in the telescope.

As the moderator wrote, you don't want to botch this! Two sensible
options are full-aperture filters and eyepiece projection. Using any
kind of focal-plane blocker is risky. If you have to ask for advice,
you shouldn't be doing it.

You might want to consider H-alpha imaging. That's safer (if your
filter is sound), and I believe H-alpha flares are more common than
white light flares.

There must be lots of internet resources on "solar imaging." I
expect you can get better answers in sci.astro.amateur if that group
is still active.

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