Sun Imaging

[chuckywiz]

Howdee folks

Finally got a few days off and some decent weather so thought id crank out the b east and check the sun out. Ive got one of those silver filters that go over the front of the scope. Had it for years and never ever used it.

Anyways - im all set up and taking photos and cant see too much but a white disk (the sun). Are there times where there is no sun spots or prominances. would my exposure time likely be too high.

Im using the nikon d3200 attached to the 10 inch newt.
ive tried isos 400 - 1600 and all manner of exposure times all the way down to 1/3200th and can really not see anything of any interest.

Ben

[rustigsmed]

hi ben,

possibly out of focus?

Rusty

[chuckywiz]

i thought that too.... but i had the missus focus it whilst i was in the shade watching it.. pretty sure im in focus.. the disc is a nice crisp shape. think i got one little spot to the top right of the sun.. but not to sure....

the joys of experimentation


Ben

[julianh72]

I was looking at the Sun on the weekend and wondered the same thing. It turns out that the Sun is just about as free from sunspots right now as I've ever seen it - check out "The Sun Now" on the SOHO page:
http://sohowww.nascom.nasa.gov/data/realtime/hmi_igr/512/

[chuckywiz]

yeh ok wow.... that one sun spot i can see might be the one on that image.. so maybe i am doing it right...

thanks for the link... love the yellow..

Ben

[Merlin66]

Ben,
Your white light filter will show sunspots and faculae (brighter areas near sunspots). You won't see prominences or filaments, that requires a specialised Ha filter system - like the one on the Coronado or Lunt.

[chuckywiz]

Thanks for the info Ken, much appreciated. ive had this filter since i bought the scope and never used it.. not sure ill bother with it again but time will tell....

i think if i was to go into sun imaging i would go a proper solar scope.. i love seeing the solar flare and other features. time will tell....

Ben

[OzStarGazer]

I have the same filter as you (Baader) and yes, there have been days when I could not detect any sunspots (or just one or two tiny ones), in particular at the moment. I have a couple of photos that look almost "spotless"...

[Atmos]

Any white light filter on the market doesn't allow you to see anything other than sun spots because it is allowing only a little bit of many wavelengths through. All of the different wavelengths basically wash out any texture on the sun.

This is where Ha Solar Telescopes are fantastic, I have a little Coronado PST (Personal Solar Telescope), only very recently bought a camera that I can actually take images with (QHY5L-II), these telescopes have next to zero back focus.
As this telescope type allows only the ~656nm wavelength through (hydrogen alpha). The narrower the transmission (<1 angstrom) the finer detail that you will be able to observe.