Quote:
Originally Posted by Startrek
Thanks Raymo
Have you ever imaged in Sydney ( mega skyglow )
I took a 2.5 minute test exposure at ISO 800 and the RGB histogram curves ended up on the 2/3 line
The capture screen on BYEOS was like a white sheet
Dropped it down to ISO 400 and took a 2 minute test exposure , histogram curves ended up right on the 1/3 line and screen looked bright but within reason ( I knew Startools could wipe the gradients , vignetting and skyglow away )
You are spot on Raymo regarding the light gathering capability of the new 8” f5 compared to my old 6” f6 ( chalk and cheese )
I’m going to have to re think all my settings in the future for Sydney and at my dark site down the coast
Thanks
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Martin, the skyglow accumulates linearly with time, as does the thermal noise.
Couple to the read noise, which is worse at ISO400, and you're really better off at ISO800 as raymo says
The "bonus" at 800 is that you can get 2x the number of subs in the same length of time, and the random noise will be controlled better.
Nice image all the same
