Solar masking

[DrBobAZ]

Greetings

I have never done prominence imaging of the Sun before. I realize the standard method is to use a super narrow band (expensive) filter and captures only the emission lines and filters the vast majority of the wideband emission.

I have been using the overexposed pixel feature on DSOs to get my stars a bit less saturated.

My question is if I use the mask feature on the sun just using a white light filter, would there be any hope in imaging prominences? I would think high enough gain, I could get the h-alpha even through a white light filter.

It would certainly be the low cost alternative if possible!

Thanks for any insight

Bob

[admin]

Hi Bob,

my suspicion would be that even if the scope only scatters 0.01% of light, the amount of scattered light from the solar disc would be far more than the light coming from the prominences. I believe that in some professional solar observatories they use a physical obstruction to block the light from the disc of the sun, allowing the prominences to be seen, but I've never heard of that being done in an amateur setup.

As with all solar observing attempts, proper use of filters is essential...

cheers,

Robin

[DrBobAZ]

Hi Robin

Thanks. (and thanks for the filtering warning )

I tend to agree. If there was still a blackbody component in the corona, then that would likely swamp any line emission.

It is encouraging that disk blocking is an established procedure in observatories.

Maybe I should just try and see what happens.

Bob

[turfpit]

Bob

A search on astrobin.com gives https://www.astrobin.com/search/?q=solar+prominence. Plenty of examples of equipment used and processing techniques.

https://skyandtelescope.org/observing/c ... ominences/

https://starizona.com/blogs/tutorials/solar-filters

White light filters for sunspots and Ha filters for prominences seems to be the message.

Lunt and Coronado equipment feature prominently.

How deep is your wallet?

Dave

[Jean-Francois]

Hello Bob,

If you want to observe only the prominences, then you can have a look at the coronagraph.
But today the telescopes and the cameras allow to take images of the sun disk and the prominences ... but only with a narrow band (for example Ha).

The spectroheliography allows the observation of the prominences ... at any wavelength (if any prominences are present).

Regards,
Jean-Francois

[DrBobAZ]

Thanks to all for the replies.

My wallet is not deep enough to justify dedicated narrowband solar instruments, hence my question originally.

I considered further, and even though I might mask the solar disk leaving the corona, any broadband emission in the corona would swamp the H-alpha if I just looked at the entire spectrum.

So in effect, I am in agreement with both of you that its pretty much narrow band or just don't bother.

Bob