Upgrade Camera or Lens?

Trying to decide if I should upgrade from a D3100 to an upper level camera body or keep D3100 and upgrade lens. I typically enjoy day time landscape photos, and am trying my hand at some star photos. Currently just have kit 18-55DX & a 55-300 DX. I realise that star / night photos require higher ISO and mine seems to be full of noise when I crank up ISO. Thus prompting change consideration. Suggestions most welcome! Thank you.

Welcome to the forum,no idea about night photography but normally the answer is lens first,but this could be a different situation,like you i will wait and see.

Thanks Mike. Fun choices.

Welcome to the forum. I bought a second body D3200 as a second camera to shoot at night and it's pretty bad. You can't really go above ISO 400 on long exposures. My old D7000 was good up to ISO 1600 and my d7100 is about the same. You can get a new D7000 from HDEWCameras for £395 last time I looked. I would go down this route if you interested in night photography then get a faster wider lens later on for night shots. I've just ordered a D750 for nighttime as the D7100 doesn't do exposure preview in liveview where the D7000 did so avoid the D7100.

Welcome.

You don't need very high ISO for nighttime shots, but a fast wide angle prime lens will make a big difference. Also a tripod.

Morganinaboat said:

Trying to decide if I should upgrade from a D3100 to an upper level camera body or keep D3100 and upgrade lens. I typically enjoy day time landscape photos, and am trying my hand at some star photos. Currently just have kit 18-55DX & a 55-300 DX. I realise that star / night photos require higher ISO and mine seems to be full of noise when I crank up ISO. Thus prompting change consideration. Suggestions most welcome! Thank you.

Click to expand...

Actually, we may need both high ISO and wider aperture.

With a camera on a fixed tripod, we still get motion blur on the stars due to the rotating earth. Specifically, 20 second exposures at f/2.8 at ISO 3200 at 14mm will show the Milky Way (if under a very dark sky), but also shows this motion blur, and it only gets worse with longer exposures or longer focal lengths. If doing rotating star trails, this blurred trail won't matter (it is the whole point), and dimmer stars don't matter, and then much longer exposure works (in lieu of ISO or fstop).

But if doing Milky Way shots in dark sky, you need either:

Higher ISO for shorter exposures.

Opening lens wider (2 more stops open, say f/2, is same as 4x higher ISO)... for shorter exposures.

Or both.

Or alternately, for longer exposure to see weaker stars, an astronomical telescope mount to rotate the camera exactly opposite the earths rotation, therefore keeping lens motionless on the stars during longer exposures.

A very inexpensive build-it-yourself astronomical mount that mounts on your tripod that is very adequate for a camera is a "barn door mount" (has been called a Scotch mount). Simply two wood plates hinged together, with a screw to lift the top plate (in calculated manner).

See http://www.google.com/search?q=barn+door+mount

Calculated screw threads (and calculated distance from screw to hinge) rotated slowly by hand (a faction of a turn, every 15 seconds, per calculated instructions), to keep the camera motionless on the stars. With attention to turn it, adequate for exposures up to several minutes. Some put a 1 RPM motor on it to turn the screw.