Art Rosch wrote:
To answer Steadyhand's question, the time limit before stars begin to blur is the focal length (or equivalent)
divided into 600. 20mm? 30 seconds. Etc. So you can see that wide
FL's offer more latitude. You will also get a better optical result by stopping
down one step from wide open; fewer edge aberrations.
art
Why divided by 600? What is the significance of that number?
Thanks for this info by the way I've been dying to photograph the heavens, I just need clear/clean skies to do so!
I don't know the reason for the number 600. It works. Must have something to
do with the rotational velocity and circumference of the earth. that would
be an interesting web search, to find out the reason.
Beautiful, Dan. Almost surreal with the painted foreground and the fisheye view. Great decision to get the stars in clear as any tracks would have spoiled a great pic.
skyview wrote:
WOW!!!!
Nailed it, great job.... now that low noise is reason for me to want D3 so I can do night work D2x here and is a bit noisy at those higher iso values.
Did I say WOW!
There are some lingering issues with the astrophotography and the D3 (also D300).
This is really amazing! The Milky Way alone would have already been beautiful, but then the Chimney Rock and the brushes in the foreground ... great!!!
As for using a tracking mount, I don't think that this picture would have benefitted from it, since then the rock and the brushes would be motion blurred.
The 600, by the way, comes from a simple calculation which just assumes that the earth turns once around its own axis (360°) in 24 hours, and that a star trail of around 5 pixels (on a 5D) is still acceptable. No magic involved!
I've been dying to photograph the heavens, I just need clear/clean skies to do so!