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View Full Version : My first star trail



Lovin
08-28-2011, 12:11 PM
It is so hard to focus in the dark. I had image stabilizer off and autofocus off as well. Anyway, this is my second attempt of taking star trail picture, considering the long exposure, and o coffee and some chocolate didn't helped me too much, staying up all night :)

I will keep trying until I'll get the perfect one. Maybe I'll rent a lens for that, because I don't have any 2.8 or a very wide lens at 4.0

Hope you like it.
Thanks,
Lovin

Iguanasan
08-28-2011, 12:49 PM
Nice shot. I haven't had any experience with this yet but I would think that you'd rather go f8 to f16 and just leave the shutter open longer.

Marko
08-28-2011, 01:16 PM
I quite like the tress on the right here - adds to the comp. Really fun play here!

Lovin
08-28-2011, 01:27 PM
Thanks guys !

@Iguanasan: you can't use F8 or more in this kind of photography, because it will be so noise, that you couldn't separate the stars from the noise. From what I read, the f5.6 would be a maximum, but I'm still reading about this.

Setup for this photo: ISO 100, f 3.5, 18mm on bulb setting with 90 minutes exposure.

Iguanasan
08-28-2011, 01:33 PM
Really? Interesting. What causes the noise I wonder? Hmmm...

asnow
08-28-2011, 09:27 PM
Really? Interesting. What causes the noise I wonder? Hmmm...

My guess is if you stop down more than f5.6 it is the longer exposure time that creates the extra noise. Besides it is infinity, you don't need much DOF.

Iguanasan
08-28-2011, 09:59 PM
It depends upon your foreground elements. My 50mm lens at f4 or f5.6 focused on something 50 feet away would not actually focus on infinity and so the star trails would be blurry. I'd have to go to at least f9 or f11 to get a proper focus to infinity. Going wide angle helps as 18mm on my kit lens would be focus on infinity and on the 50 foot object.

Maybe I'll get a chance to try it out myself. Just for fun. I can't possibly see how a smaller f-stop would cause noise.

Lovin
08-29-2011, 12:10 AM
One helpful link : Oleg Novikov Photography » Star trails photography tips (http://www.olegnovikov.com/technical/startrails/startrails.shtml)

Barefoot
08-29-2011, 09:59 AM
Really? Interesting. What causes the noise I wonder? Hmmm...

Heat build-up in the sensor due to the long exposure. I've read where some feel that long exposures might contribute to the formation of "hot pixels".

aubintbay
08-29-2011, 08:03 PM
Very nice. This is something I want to try but just have not gotten around to yet. Hope my first tries come out this well.

Greg_R
08-30-2011, 09:31 AM
Great shot, I'd love to try this one day (night) as well.

Is this a single exposure, or did you use stacking software?