star trails

[akimartymar]

I plan on doing some night photography somewhere there is really no unnatural light where I can keep my shutter open a long time and catch some star trails behind my subject. I'm hoping to expose long enough where the subject looks well lit but where you can still tell it's night time. Any tips on what aperture to use and how long to leave shutter open?

[xjben]

I'd search Google for sites that talk about Astrophotography. Look for sites with tips...and also, do a Google Image search for "star trail", find a few that have different trail lenghts and list the exposure time, that will give you an idea of how the longer times make longer trails. I've seen trails from short exposures, like 5-10 minutes, up to photos that run for hours. The really, really long ones are probably best taken on a film camera, I'm guessing.

[akimartymar]

These are going to be done with a Bronica medium format camera.

[venchka]

Search the forum. Probably in Landscapes. There is a really nice photo taken in Big Bend with a MF camera, a Mamiya 6x7 I think. Working from memory, ASA 100 film, 1:5.6, 4 hours if my brain is working right.

[venchka]

Found it. Is this the type of image you're after?




Mamiya RZ67, 110mm F2.8 @ 5.6, 4 hour exposure on Kodak E100G

Good luck! Please share your results with us.

[venchka]

My brain is still working pretty well. I nailed the exposure!

[akimartymar]

Yeah, that's something like what I was going for. Maybe not quite as long on the star trails. Also, that picture looks like those trees and the grass were hit with some other light or something. They are so bright but the mountain is still total sillouette. If you're ever seen some of Michael Kenna's night work then you probably know what I'm after.

[chloew]

Here's some pictures along the lines of what I think you are looking for. They were exposed by the moon light.

http://www.texasphotoforum.com/forum...ad.php?t=24484

Here's the relevant EXIF data on the picture posted by PeteQ. Looks like a 5 minute exposure at f/5.6 at ISO 400. The exact exposure time will depend on the amount of moon light present.

Tag Name Value
0110 Model NIKON D200
829a ExposureTime 300.0
829d FNumber 5.6
8827 ISOSpeedRatings 400
920a FocalLength 24.0