The FWHM of the etalons are not the ones provided by the manufactured but values actually measured.
Interpretation:
As the FWHM decreases the parasitic contribution of the photosphere reduces and a higher layer of the chromosphere is sampled.
With a 1.0 A FWHM etalon:
- photospheric granulation is still visible though the chromosphere. This explains the grainyness of the image.
- the filaments are faint and poorly differentiated.
With a 0.3 A FWHM etalon:
- photospheric granulation is no longer visible,
- the smaller spots (photospheric level) have disappeared, covered by the fibrils (chromospheric level),
- the ombra of the larger spots are partly covered by the fibrils.
Interpretation:
As the
FWHM decreases the parasitic contribution of the photosphere reduces
and a higher layer of the chromosphere is sampled.
- the double-limb effect increases with the FWHM.
Unprocessed 16-bit files
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- the double-limb effect increases with the FWHM.
Unprocessed 16-bit files
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