Hi,
in his talk on Practical Astronomy Show Robin Glover showed a slide "Light Pollutions Rates" which shows 2.6 as the rate for a "Standard Observer" (i.e. Bortle 5, Pixel size 3.75, CMOS mono sensor, QE 50%, f/6. The number 2.6 is further used in the subsequnt calculations.
On the website http://tools.shapcap.co.uk the Light Pollution calculation leeds to 2.3 electrons per pixel per second.
What is the right number to do further calculatins with?
Kind regards & Clear Skies
Dietrich
Deep Sky Imaging: Lightpollution Rate 2,3 or 2,6 ?
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Re: Deep Sky Imaging: Lightpollution Rate 2,3 or 2,6 ?
Hi,
the tools.sharpcap.co.uk site has the correct calculations in it (although they are only approximations anyway). I suspect that I had made some of the slides for the talk with the value of 2.6 rather than 2.3 due to a miscalculation and kept the figures (and the slides) rather than re-work them.
If you try putting Bortle 4.9 and 5.1 into the web site you will see how sensitive the final figure is to the change in Bortle number.
Robin
the tools.sharpcap.co.uk site has the correct calculations in it (although they are only approximations anyway). I suspect that I had made some of the slides for the talk with the value of 2.6 rather than 2.3 due to a miscalculation and kept the figures (and the slides) rather than re-work them.
If you try putting Bortle 4.9 and 5.1 into the web site you will see how sensitive the final figure is to the change in Bortle number.
Robin