Sky photo

[Tringa]

I have been trying star photos recently.

There is clearly a limit to the exposure time before the stars start to trail and I think I may have exceeded it here.

A long way from being a good shot - more just for the record.

Details - taken about 20:20 12/01/2012. Exposure 18mm lens at f4.5, 30s ISO 400. The colour on the hillside comes from security lights as a nearby school.

Dave

[Bobobird]

Cool shot.
Have been trying to get something like this but the skies just have not been co-operating of late.

[herbert]

Hi Dave,

You can use the 600 rule to determine when you will get star trails.

Basically you divide 600 by the effective focal length of the lens. E.g a 18mm lens would be 600 / 27 = 22.2 secs.

You must use the effective focal length. So an 18mm lens would be around 27mm if it was a crop camera.

It is just a rough start. I am sure it matters how close to the equator you are as well since the earth is spinning faster. However I did not make up the rule. Have a search on the web and you should be able to find out more articles on star trails, the 600 rule and night shots in general.

I like the red glow on the earth in your shot. Makes it look other worldy. Was it windy? I think there is some motion blur in the trees. Perhaps try another vantage point with no moving structures next time and see if you prefer the static look over a fluid one.

Alex

[Tringa]

Thanks for the comments.

Cheers for the info on the 600 rule, Alex and yes, it was windy at the time.

Dave