How can I get great night shots?

[net1994]

I will be traveling to Maine in the next two weeks and have a few questions about night time photography. I have done night shots in the past with generally less winners than loosing shots.

1. I have always had a problem of trying to focus on X thing at night. Is there a special trick to find focus at night? If I have something close by to focus on I sometimes use a flashlight to temporarily light up the item and make sure focus is ok. Or a laser pointer. But for far off objects (stars in the sky or a mountain far away) it’s impossible to tell. Used the old 'trial and error' approach and it is extremely frustrating. Has anyone tried the Nikon DG-2 magnifier? I hear it only magnifies a portion of your view and not everything. This is fine with me.

2. I think the moon will be half full when I’m out. Will this make it hard to get these ‘galaxy’ type shots even if I’m far, far away from any urban/town lights?

3. I need to take LONG exposures with my Nikon D300. Up to 6 minutes I think. But noise quickly becomes a problem at that point. To get enough light I will have to do long exposures, but I'd like to avoid start trails/swirls for some of my shots. Is there a way I can take multiple exposures and then combine them? This is a great example of what I'm hoping to get...
http://www.paintbypixels.com/photos/661329099_hMg56-O.jpg

[craig_d]

1. At night, for objects too far away to illuminate with a flashlight, the hyperfocal distance is your friend. Wide angle lenses make this particularly convenient since the hyperfocal length gets shorter as your lens gets wider. For celestial objects, manually focus to infinity.

2. Yes, the half-moon will seriously interfere with stars and other even dimmer celestial objects.

3. A shot anything like the one you posted is impossible with a single long exposure, because the stars will move relative to the landscape. You'd have to combine two shots: one long exposure with the camera on a motor-driven equinoctial mount to get that beautiful star-filled sky without trails, plus a second shot with the camera motionless to get the land. I have not actually tried this, but I don't know how else you'd do it.

[dm50384]

try boosting the iso to 800 and use a f-stop of 2.8. this will be fast enough to avoid startrails. larger f-stops doesn't get all the stars without a real long shutterspeed.it is amazing how fast the earth rotates!

[El Gato]

I came to this sub-forum looking for an answer to why my night shots (see here) turned out grainy, and thanks to dm, I think I have my answer.

Given the late (or early as it was) hour, I forgot and left my ISO set at 200. Am I correct then in making the leap of faith, that if I set my ISO to 1600, 3200 or beyond (my D300 goes higher), that I will be able to clean up my image and significantly reduce the grain?

Is there a point of diminishing returns, meaning going beyond ISO 800, 1600 or even 3200, will not improve the clarity of the final image?

The Zion shot was a 46 min. exposure, shot at f3.5, with a 12-24mm wide angle, taken between 2:30-3:16am MST. I was looking to get the star trails.

Suggestions on improving the final image, in-the-field (e.g., different f value, longer/shorter exposure, ISO setting, etc)?

Thanks!

[El Gato]

Oh, BTW.....

maybe 46 min. was a tad bit too long for the exposure. Thus, another question, how can one decide/tell what IS a proper length of time (exposure) for such a shot?

Too short and the trails do not appear, too long and too much light enters the image. Maybe if I started closer to midnight, I would be less impacted by the coming dawn. I just won't sleep any more.

Also the evening was super clear, altitude was at approx. 3000 ft. (+/-), and the sky was just ablaze with stars. Possibly the billions and billions of stars and their associated light contribute to the potentially over exposed image.

When taking such long exposures, there is little opportunity for many multiple shots in one evening before the dawn's light begins to wash out the sky.

Thanks in advance everyone!