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Twilight Observing?

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JAM
JAM's picture
Twilight Observing?

This morning I observed W CYG and miu CEP after astronomic dawn, both of which were ~1/4 magnitude fainter than the established curve. Solar altitude was between -12 and -10˚ at the time. 

Since both are fairly (or very) red, I defocused my binos. Red stars are apparently extra bright in twilight, but the V curve for miu CEP suggests I'm too faint as well.

Do any experienced observers have suggestions for better twilight accuracy? Thanks!

onj
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Twilight Observing?

Hi,

I generally quit observing variable stars before the start of Nautical Twilight when the solar depression is 12 degrees.

I usually defocus my binoculars a little anyway.

John

 

JAM
JAM's picture
Sounds like good advice,

Sounds like good advice, thanks John!

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