paul3221 wrote in post #16818445
Shoot wide and fast. The wider the lens the longer your exposures can be without star trails. On a Full Frame Camera like yours, the rule of thumb is 600/focal length. So, with a 20mm lens, you should be able to do 30 seconds. The larger aperture the better. On a wide angle lens, you don't need to worry so much about DOF. I shoot most of mine at F2.8. Focusing can be the toughest part. I find it easiest to find a bright star or planet, zoom in with live view, and manually focus. Once you've got the focus set, you shouldn't need to touch it.
Is there a specific equation you can reference for this. I think it was mentioned in the blog I linked to but it was not spelled out. Thank you for the advise.
EDIT: After asking this I understand the math now. I was reading a little two far into it. Here is the quote from the blog I pulled which breaks it down a little more:
"Stars move at about 2.5 degrees every 10 minutes around the circumpolar positions. You can calculate exactly how long you can expose for without noticing movement but the process is a little complicated, depending on latitude, pixel pitch of the sensor, focal length, which part of the sky you are viewing etc.
A simple equation for maximum shutter time is 500/focal length (in 35mm terms).
This means a 10mm (crop) or 17mm ( 35mm) lens you can shoot about 30 seconds without seeing star movement at a decent sized print."
Geonerd wrote in post #16819105
What are you doing?
You're going to have to apply some basic photographic principles, rather than depend on your fancy camera to make everything right.
Set the lens to full wide or, if you're paranoid about sharpness, a stop less. More light = better s/n, and shorter exposures make for sharper stars. Vary shutter to achieve the level of star streaking, if any, that is acceptable. With a 24mm lens, your 30 seconds should be OK. Then run the ISO up until you get a bright enough image or run into noise issues. Keep in mind that the in-camera NR may not do kind things to faint stars.
What am I doing?.....If I knew the answer to that I would never have posted. Thanks for your two cents.
HBOC wrote in post #16819154
To get the stars/milkway to show up, you need to let in as much light as possible. So the faster the lens you have, the better. I may pick up an f/1.4 lens this year
On my shot, it was one shot. Focused to infinity, and used ISO 1600 for 37.5 seconds. With the D700, i found higher ISO introduced more noise. I have a D600 now, so it should handle noise much better - but still wouldn't want to go a ton much higher in ISO.
The great thing about night photography is that it is trial and error. You could take the settings I used for this shot, apply them for your shot - and it may not work. The light pollution is from Seattle/Puget Sound area, so it "helped" keep my exposure shorter. But those settings would get you in the right direction.
Also I don't usually blend night shots. Only time I would do it is if I shot earlier at night (dusk) and wanted to get more of the stars when it was still a little light out.
Do you have a high-res version of the photo? I would love to see how detail the image is. Thank you for your insight.