Stars and Landscape

[binaryfaith]

Hello everyone.

I've got a question about shooting an LF camera at night with a chinese made Shenhao 4x5 view camera with a Schneider 90 Super Angulon lens.

My friend has a house way up in Boontsville county far away from the city lights of San Francisco. At night the stars blanket the sky in a brilliant display. I was wondering how I could capture that along with some of the rolling hills as a landscape backdrop. Film recommendations? Reciprocity issues? Aperture? Length of exposure?

Anyways thanks in advance.

Cheers Everyone :)

[Sevo]

The real issue is with the stars effective brightness - to capture them, you have to track them. There are plenty of reasonably affordable motorized head rigs for amateur astronomers - but you can't track the sky and freeze the landscape simultaneously, so it is either "star traces above a landscape", or you'll have to composite (whether in photoshop, in the lab or with double exposure and mattes on the camera).

[binaryfaith]

Thanks :) so if I can tolerate star trails any tips on aperture and exposure? Film type?

Cheers :)

[Vaughn]

Black & white -- or color? T-Max 400 would work.

Aperture -- this will help determine the type of trails you get. The middle aperture will give you thinner, sharper star trails. Wide open or closed down, the limitations of the lens comes into play and the trails are wider and a little more blurred.

Unlit landscape will be black. You might consider one shot while there is still light out to fill in the landscape a little (not a full exposure), then wait until dark for the stars. You may need to use a dark red or orange filter (w/ polarizer?) to keep the sky dark during the first exposure. If you have them for that lens!

Vaughn

[GPS]

...Aperture -- this will help determine the type of trails you get. The middle aperture will give you thinner, sharper star trails. Wide open or closed down, the limitations of the lens comes into play and the trails are wider and a little more blurred.
...
Vaughn

Stars are a point source of light. In such a case the usual nominal aperture/exposure relation is not valid. The exposure depends on the actual physical aperture size. Hence f5.6 on a 300mm lens and f5.6 on a 90 mm lens gives completely different results. It has been discussed many times over on this forum.

[Richard Wall]

For a start you could try something like F8 and around one hour exposure with 400ASA film. Although, I would probably do some bracketing as well. Use the light from the moon to illuminate the landscape. Try not to get the moon in the shot as it will cause flare etc. The moon will be your primary source of light to illuminate the landscape and it's brightness varies throughout the month, so exposure time is difficult. If you shoot on a night when the moon is full, it will look like your scene is in bright sun but you will also have to adjust your times. Take a look at the nocturnes website for more info and some great night images. http://thenocturnes.com/index.html

Hope this helps.

Richard

[pocketfulladoubles]

As a point of calibration, I needed 5 hours at f/16 ASA 50 with a very bright full moon behind me, and it was about right to illuminate everything in view to about zone iv.

[binaryfaith]

Humble thanks to those that provided helpful tips

[tgtaylor]

Star trailing is dependent upon the aperature of the lens and the declination of the star. For an 85mm lens, Norton's 2000.0 Star Atlas ans Reference Handbook gives the following exposure times (in seconds) at which star trailing becomes evident:

0 degrees: 6 seconds
40 degrees: 8 seconds
60 degrees: 12 seconds
80 degrees: 34 seconds

Thomas

[Vaughn]

Stars are a point source of light. In such a case the usual nominal aperture/exposure relation is not valid. The exposure depends on the actual physical aperture size. Hence f5.6 on a 300mm lens and f5.6 on a 90 mm lens gives completely different results. It has been discussed many times over on this forum.

Negatory, big buddy! What I am talking about is a lens ability to sharply reproduce those little points of light called stars. In the middle f/stops, the lens is sharper, less prone to flare, etc. So the star trails are thinner. Wide open or shut all the way down, distortions inherent to the lens creates a slight flaring of the light, giving star trails that are wider. A fact of optics, true for lenses of any focal length.

Vaughn

[tgtaylor]

Star trailing is dependent upon the aperature of the lens and the declination of the star. For an 85mm lens, Norton's 2000.0 Star Atlas ans Reference Handbook gives the following exposure times (in seconds) at which star trailing becomes evident:

0 degrees: 6 seconds
40 degrees: 8 seconds
60 degrees: 12 seconds
80 degrees: 34 seconds

Thomas

I believe that I copied that wrong last night as I was listening to the Angels/Yankee game. Star trailing is dependant upon the focal length of the lens and the declination of the star. Although Norton's Handbook didn't specify, I suspect that the above focal length is that of a 35mm camera.

Also, I recall the handbook recommending stopping the lens down 1 stop from maximun aperature.