90min exposure, ISO 100, f8 O'Leary Lake, MN

My first attempt at night sky long exposure. Taken with the Sigma lens

at 10mm, f8, iso100 for 90 minutes. I tried a 250min exposure, but the

camera ran out of batteries before it could get through the dark frame

subtraction because I had noise reduction on. Thanks for looking.

 

-Tim

I suggest with digital you try a different method for star trails. If you have a large memory card (2 gigs or more) you should try taking multiple exposures and then having photoshop or a program called "Startrails" overlap them. Set your camera to burst mode, ISO 800, 30 seconds, and your widest aperture. Turn off noise reduction.

Ive seen the multiple stitched photos and there always seems to be little gaps where the camera cycles the shots. Ive never liked the look of them. The trails look more like stringed beads than continuous arcs. If your method removes those, then id be willing to try it out, but to date I have not seen a stitched photo I have liked.

Yeah, usually that stringy bead effect occurs when people don't turn off noise reduction. Check out some of my star trail shots here: http://www.photo.net/photodb/folder?folder_id=738685

 

The 3 left star trails were done using the multiple exposure method. The one in the middle may suffer from that stringy bead effect slightly, just because the last two exposures I took a few minutes later, because I had to set up the flashlights and flashes in order to light paint the foreground.

 

I highly suggest the multiple exposure method. Not only do you have better control over the exposure (you don't have to worry about blowing out the sky or the foreground) but you won't lose an full 2 hour image due to the battery dying during noise removal.