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Recently I observed profiles of hydrogen Balmer lines in Sirius spectrum with spectral type A. I used LowSpec spectrograph with 1800 l/mm diffraction grating and APO APM 107/700 on HEQ5 mount.

H-alpha:

1414965034_SiriusHalphaeng.thumb.png.810932f0094217b1fa2f356871aced6d.png

H-beta:

1856949549_SiriusHbetaeng.thumb.png.3404064d9fc7fedaf4d99969d306b70a.png

H-gamma:

1149291619_SiruusHgammaeng.thumb.png.6d8c9f5c1f61916565364fbc84477a44.png

H-delta & H-epsilon:

1572688961_SiriusHdeltaandHepsiloneng.thumb.png.6ff8c7905da1fe73e0c26f79b2f42b9a.png

I had some problems with stacking, so I used the best single frames in analysis.

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Well done, mate!!

Shows well the capabilities of the LowSpec.

What were the stacking issues? Just interested.

Ken

 

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Thanks.

Robin, I had to refocus often. For example I split the solar spectrum in 60 segments to get sharp lines in whole visible range. Only the center of image is sharp, peripheral areas in both sides are defocused.

Ken, I tried to stack with using BASS software, but after comparison with single frame I had too big differences. Last night I had 5 good stack and one was wrong.

Marius

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