Which settings for star trail on dslr?
Hi i'm still getting used to my Nikon D90. I'd like to know which exact settings to use to create a star trail? I live in a village with no street lights up my road so very little light pollution.
What do you think, knowing what you do about exposure?
I'm sure you know you will need a tripod
I'm also sure you know you will need to leave the shutter open long enough to allow the earth to move under the stars to produce those trails.
And I'm sure that you know you will have to manually focus the lens at infinity (auto-focus does not work in extreme low light
And finally I'm sure you know how to use tests to pick the correct lens aperture so you do not over or underexpose the images.
Knowing what you do, I'm sure you will be able to determine the proper "settings" to shoot star trails
Little bit snippy from fhotoace there.
Oh well.
The thing with astro photography is that the earth moves very slowly, around 15 degrees per hour.
So to get those long streaks you will need a few things:
A very long exposure.
A very good battery (enough for the long exposure and enough for the subsequent long exposure noise mask exposure)
A very steady tripod
A cable release
Other things that will help:
A tripod. A sturdy one. Manfrotto, Giottis or similar.
A cable remote, maybe even one with self timer.
Putting the camera in B mode.
Keep the ISO low, keep the aperture small, try and avoid using filters as they can often produce ghosting in these kind of situations.
Using a small aperture (if you have an AF-D lens then set it manually on the lens rather than through the camera, saves battery drain)
If you want to accentuate the star trails then use a longer lens, the 15 degrees per hour moves more quickly across a long lens than a short lens. You can still get foreground stuff in, even with a long lens.
Point your lens towards the pole star under the centre AF point. The movement of the sky is more pronouced at the poles.
Look into star trail stacking… Often less frustrating than single long exposures, though a bit more work at the other end.
Hopefully thats a little more friendly and a little more helpful.
If you want a good star trails, get a 35mm SLR with a manual shutter.
Don't use your D90 for that.
The long times needed to capture star trails won't work even with a fully charged battery. You might have to buy a power pack for the D90.
The sensor will get heated up in such exposures leading to noise that will appear like blotches of light on some parts of the frame. Nikon has incorporated a noise reduction method in camera bodies for long exposure related problems but it is not a very effective one.
With a film based camera your only worry will be correcting the reciprocity failure.