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I was searching through my photos and found this one, from the top of a mountain (Mt Rogoona) in late December.
I remember taking it, hoping to get the "centre south" - the point where all stars rotate around. Right direction, but it seems I aimed too low in the sky.
Surprising how high in the sky this "circle" point is in Tasmania at the height of summer.
Still an interesting result.
About 13 minutes exposure, ISO 200, 50mm F1.4 lens at F2.8 for this image.
Exif info intact.

Simple but cool. It's making me dizzy.

>>Surprising how high in the sky this "circle" point is in Tasmania at the height of summer.

That would be the South Celestial Pole, its exactly the same elevation above the horizon as it is in Winter equal to the latitude.

Did you notice the dew on your lens? Thats what causes the tapering/fading trails

Gordon

Pretty awesome mate

Add any silhoutte to make even a cooler picture!

surenj wrote:Add any silhoutte to make even a cooler picture!

You mean like these?

That would be the South Celestial Pole, its exactly the same elevation above the horizon as it is in Winter equal to the latitude.

Yeah. I put my head in gear, thought about it, and what you say makes perfect logical sense.
Just that the objects in that south celestial pole would be quite different between summer and winter.

Did you notice the dew on your lens? Thats what causes the tapering/fading trails

I didn't check on the fog on the lens too much in the first image, I was on a mountain and it was too cold. Lazy? Perhaps. Interesting to know why they fade like that though. Thanks.

tasadam wrote:...Just that the objects in that south celestial pole would be quite different between summer and winter.

Nope, the SCP is a point that only apparently moves amongst the stars very slowly, due to the Earth's axis precessing, you wouldnt notice it in a lifetime. The sky will rotate around it once every ~23hours and 56 mins, so every 24 hours its moved around 1 degree of rotation past the previous day. In the course of a year it amounts to one full rotation extra - due to Earth revolving around the Sun.
If you have a flat S horizon you can see all the stars within ~40 deg (depends on where in Tas you are, but equal to your latitude away from the SCP) all year round, what is above the pole at 6pm tonight will be below it at 6pm in 6 months, but will again be above it in 6 months at 6am.
Go further South to the pole and the sky rotates around the zenith, so all the southern stars are visible all year, although the Sun hides most of them for 6 months, plus those hidden by twilight for some extra months when the sun is less than 18 degrees below the horizon

Gordon

tasadam wrote:

surenj wrote:Add any silhoutte to make even a cooler picture

You mean like these?

Yeah...Awesome...