Sun with single polarising filter

[Piero]

This afternoon I observed the Sun for about 3h at 51x, 72x and 103x with my Lunt.

I observed without, with variable or single polarising filter.

Although the seeing was not great due to the wind, a hint of granulation was still visible at moments.

I noticed that I much preferred the views with single polarising filter rather than the two mounted together. More in detail, I enjoyed when it was rotated at '45 degrees', therefore in between bright and dark. This is the same configuration I use when watching planets in the twilight. I cannot explain a technical reason why, but generally I can say that the image is still bright and the contrast maximised from my point of view.

I would like to know what are the bright areas visible near penumbra zones in the sun. I noticed a few times that granulation is much more visible on those areas. They appear a bit brighter than the normal Sun surface and they are close to large sunspots predominantly. Could somebody tell me what are they called and some information about them, please?

Thanks in advance!

Piero

[Steve Ward]

"Faculae" ... http://www.isf.astro.su.se/highlights/faculae-explained/

The light from a Herschel wedge is already polarised so using one more polarising filter is all that's needed to rotate to adjust the brightness .

[Piero]

Thanks a lot for answering both my doubts!

[Pig]

Here is the Wikipedia explanation.

A plage is a bright region in the chromosphere of the Sun, typically found in regions of the chromosphere near sunspots. The term itself is poetically taken from the French word for "beach". The plage regions map closely to the faculae in the photosphere below, but the latter have much smaller spatial scales.

I also use a single polarizing filter (variable) or the Continuum, and I keep forgetting I own one

[Merlin66]

Pig,

The plage is visible in Ha wavelengths, but not in white light.

There is no direct relationship between the plage areas and the faculae seen in white light.

[Pig]

Thank you Merlin, I just saw the word Lunt

[Piero]

Here is the Wikipedia explanation.

A plage is a bright region in the chromosphere of the Sun, typically found in regions of the chromosphere near sunspots. The term itself is poetically taken from the French word for "beach". The plage regions map closely to the faculae in the photosphere below, but the latter have much smaller spatial scales.

I also use a single polarizing filter (variable) or the Continuum, and I keep forgetting I own one

  

Pig,

The plage is visible in Ha wavelengths, but not in white light.

There is no direct relationship between the plage areas and the faculae seen in white light.

My fault! I didn't realise that writing Lunt was ambiguous as it can also be a solar telescope. I should have written 'in white light'. Thanks Merlin for pointing this out!