Skyfog Level in Punggol

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cloud_cover
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Skyfog Level in Punggol

Post by cloud_cover »

After yesterday's rain, the sky was so wonderfully clear but unfortunately I was too tired to deploy my equipment, so I decided anyway to measure the skyfog.
I used my DSLR with 200mm lens at f/4 and ISO12500. At zenith it took 3.5s to mid histogram on my camera, for an equivalent visual limiting magnitude of about 4.2 (according to this website)

http://www.pbase.com/samirkharusi/image/37608572

Not the best of course, but according to the site, a UHC type filter may make for acceptable imaging.
Ah well, maybe when I'm free to go up to Sedili (or Bekok - yep Gary, still KIV-ing :) )
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orly_andico
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Post by orly_andico »

Was imaging last night. Or at least trying.

The good news is I finally got a decent polar alignment (eventually). I could finally get round stars at 336mm on APS-C.

I think of it as skills-building.

The bad news.. at ISO 1600 and f/5, 30 seconds already pushes the green channel almost to the right-most part of the histogram. Pretty hopeless..! for the first time in my life I've managed to take 20-minute exposures (lots of 30-second ones) but the results were worse than my 5-minute totals in Manila..
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weixing
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Post by weixing »

Hi,
orly_andico wrote:Was imaging last night. Or at least trying.

The good news is I finally got a decent polar alignment (eventually). I could finally get round stars at 336mm on APS-C.

I think of it as skills-building.

The bad news.. at ISO 1600 and f/5, 30 seconds already pushes the green channel almost to the right-most part of the histogram. Pretty hopeless..! for the first time in my life I've managed to take 20-minute exposures (lots of 30-second ones) but the results were worse than my 5-minute totals in Manila..
IMHO, the image is still usable as long as none of the channels in the image saturated.

Have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
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