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BL Lacertae: prototypic blazar


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About this observation
David Swan
Time of observation
23/08/2018 - 21:45
BL Lac
Observing location
Tynemouth, UK
200mm SCT @ f/7
Baader UV+IR cut
FireCapture, DeepSkyStacker and Maxim DL
14 x 20s
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BL Lac is left of the red line. I estimate its brightness at 13.7 CV


Andy Wilson's picture

A good image of a fascinating object. This is one of the active galactic nuclei that got me interested in variable star astronomy. If you interested in contributing observations to the Variable Star Section, then please get in touch with me or Roger Pickard the Director :-)



djswan2002's picture

I do plan to get into variables Andy, and I look forward to getting yours and other's guidance at the upcoming workshop. I am currently doing a little project comparing my CV and V photometric estimates (versus published V mags) when I have my Baader luminance UV+IR cut filter in place versus my Baader photometric V filter in place. The results - so far - are I think interesting. I plan on capturing several fields containing stars with a range of B-V ratios and perhaps prepping a little letter. Something on experience with a CMOS camera, photometry and spectral sensitivity?

Andy Wilson's picture

It will be great to meet you at the workshop David. It sounds like you are doing very good prep work. Understanding how your system works with different filters will be useful and I look forward to hearing about your findings. Typically a V filter is used when accurate results are needed and when results will be combined with other observers, and unfiltered is used when monitoring objects for outbursts. Though there are no hard and fast rules as scientifically useful observations can be obtained with just about any setup.

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