Cloudy Day Spectrogram

[MarkS]

I experimented today with a slit (two Stanley knife blades mounted at the end of a cardboard tube) plus a diffraction grating (StarAnalyser 100) at the other end.

I was pleased to see that the Fraunhofer lines are clearly visible.



Imaged with the Canon 600D (unmodified) with a zoom lens at 200mm.

Mark

[JohnP]

Wonder how many people Googled Fraunhofer Lines after looking at this post... ☺

Did you mod your camera this weekend. ..?

[MarkS]

Did you mod your camera this weekend. ..?

No, I may end up selling it instead.  My tests show it appears to suffer a "star eater" hot pixel suppression algorithm similar (or identical) to the infamous Nikon algorithms.  I'm still investigating this issue in detail and I won't mod it until I'm sure I'm going to keep it. 

With a bit more processing here is my spectrum of the today's cloud cover:



Mark

[Rick]

Interesting. Going to do a sunny day one (if we get one...) for comparison?

[Mac]

the sunny one will be interesting, just to see what lines are added by the compounds in the clouds if any.

My tests show it appears to suffer a "star eater" hot pixel suppression algorithm similar (or identical) to the infamous Nikon algorithms.

Why cant they just add an astronomical mode which gives you warts and all.

Mac.

[Fay]

That diffraction grating has worked out well Mark

[The Thing]

Very interesting. Maybe once you have a sunny day spectrum you could prepare a Frauenhoffer 'dark frame' to subtract cloud added lines from future cloudy day spectra

[Carole]

My tests show it appears to suffer a "star eater" hot pixel suppression algorithm similar (or identical) to the infamous Nikon algorithms.

What a bummer.

you could prepare a Frauenhoffer 'dark frame' to subtract cloud added lines from future cloudy day spectra

[Roy]

Some cutting edge science?

Roy

[MarkS]

Hardly cutting edge. 

However, next time there's a comet I'd like to do a spectrogram of the coma to identify the elements therein.

Mark

[The Thing]

Now that sounds like an interesting project.

[RobertM]

Hardly cutting edge. 

Were the Stanley knife blades blunt ?

Other than that, it's a very interesting topic.  I did a project on stellar spectra at the OU and vowed to do more when I have time; that and photometry.

Did you use vertical binning cleaned up version ?

Robert

[The Thing]

BTW PHD 2.5.n has a spectroscopy slit guiding function.

[MarkS]

Did you use vertical binning cleaned up version ?

Yes, IRIS has a number of very useful functions for spectroscopy.

mark