- #1
smithpa9
- 40
- 22
I recently bought a Hydrogen-alpha filtered telescope (Coronado PST). Looking through it, the Sun looks mostly red as expected since the H-alpha filter only let's through visible light at a wavelength of exactly 656.3nm which is in the red part of the spectrum.
And I can see both lighter and darker red in places (filaments are darker), which I assume reflects the intensity of the light (not a different wavelength).
What I haven't seen yet, but have seen in many H-alpha pictures, are white spots called Plagues.
My question is, how is it possible to see anything white (or any other color for that matter, other than red) through a filter that only let's through red light?
Still sleepless in Cincinnati
And I can see both lighter and darker red in places (filaments are darker), which I assume reflects the intensity of the light (not a different wavelength).
What I haven't seen yet, but have seen in many H-alpha pictures, are white spots called Plagues.
My question is, how is it possible to see anything white (or any other color for that matter, other than red) through a filter that only let's through red light?
Still sleepless in Cincinnati