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Startrails help

Paul McGuire Paul McGuire 39 posts

Iv’e recently taken an interest in startrails. I’ve finally located polaris to get the circular effect.

I was messing about with the camera settings and a fairly gusty wind was blowing hence the less than perfect alignment.

The first problem i have is that polaris is very high in the sky at the moment and I can’t encorporate any foreground which is a shame. Doe’s anyone know when polaris is at it’s lowest point? I’m in the UK.

My second problem!

Admitting defeat I instead decided to get star trails without polaris but with foreground. I didn’t have much time to play with at this point so this shot is made up of 58 30 second exposures giving a total 29 mins.
There was no moon last night so no light source.
I started the shots at f3.5 and then incresed to f5.0 all taken at ISO 400. I then used flash for the last 6 exposures to light up the foreground.
My biggest problem here is noise. The photograph is way to pixelated and grainy and I’m really not sure how to overcome this. The cameras built in noise reduction facility wont let me continue while it’s working so I miss 30 seconds between each exposure which results in dots rather than lines.
I’m using canon 400D 18-55 lens @18mm and software for stacking with 2 darkframes.