Silly Star Trail Question

[John Kasaian]

I've attempted to shoot star trails long ago with a 35mm and I'm tempted to try it with sheet film, but I have a question:
In N.America, how do I determine which way the star trails will arc? Pointing my camera to the North, will they arc "u" or "n?" What about to the East?
Thanks!

[Vaughn]

Same direction as the sun/moon?

Which I believe would be east to west over the top of the North Star.

[John Kasaian]

OK so I find the North Star and that should indicate the general direction of the apex of the arc?
Thanks,Vaughn!

[Vaughn]

The "apex of the arch" should be directly above the north star which is the centerpoint of the arch...if I caught your question correctly.

So on the image on the below site, the stars are moving counter-clockwise, if I am picturing the universe correctly in my head!LOL!

http://photography.nationalgeographic.com/photography/enlarge/circular-star-trails-photography.html

[Heroique]

A picture is worth a thousand star trails.

This one is by a graduate student at the University of Virginia – clearly a combined day-time/night-time exposure. Very peaceful. I thought it would help illustrate what you’re asking, and the tips people might suggest. Note that the direction of a star trail depends on where the star “begins,” and it can trend in many directions – up-down, left-to-right, etc. What’s more, the relative length of a star trail depends on its proximity to the north star – the closer it is, the shorter the trail. And since you know you’re facing North, you should be able to figure-out which way the spinning goes.

Someone might be able to estimate the night-sky exposure time here, but it looks like it’s about 45-60 minutes or so?

[Marc B.]

A helpful site I use is Paul Neave's, Planetarium.

http://www.neave.com/planetarium/

Upper right side of page is a map window, to lock in your location on the globe.
Upper left is where you enter time and date; past, present, or future.
One click, and the sky moves with your cursor.
Click again, the sky freezes and the stars, planets, and constellations are identified.

After you determine which area of sky you might wish to shoot on any given night, you can then toggle the time function; minutes, hours, days, and see the direction and movement of objects through the sky. There is also a Zenith, and North/South pole indicator dots in the sky, (relative to your location on the globe from step one).

I'm sure there are probably other apps with a higher degree of sophistication, but Neave's site is fun, quick, and easy.
Using Neave's site, along with the extended weather forecast for your shooting locale, It's easier to plan for that perfect sunrise/sunset shot, or maybe to even capture your own, "Moon over...where ever" shot; giving you the exact time you will need to be there to get a full moon, and just the right amount of fading sunlight.

Take notes before you leave home, wind your watch, and pack a compass in your kit. Happy trails!

[Struan Gray]

For grins, point a long lens to the (celestial) east or west and get vertical streaks.

[Ari]

Cool planetarium site.
And there are no silly star trail questions.

[ivm]

Which film will you be using? I've done quite a few star trails and wide field film on nebulae and our Milky Way using MF Pentax 67. Most negative colour films tend to be poor for colour and richness due to reciprocity. Provia 100F and Velvia 100F have give very nice results even at 90 minutes.

The best astro film is - was - Kodak E200. Great red Ha response - star colours and you could expose for hours. Made no more. Portra 400 new stuff - Ektar - have given muted colours, but the Portra may do better with a lens faster than f/4.

You can see some trails here www.pbase.com/pentax67 - in the Astronomy Gallery the various films.



I've attempted to shoot star trails long ago with a 35mm and I'm tempted to try it with sheet film, but I have a question:
In N.America, how do I determine which way the star trails will arc? Pointing my camera to the North, will they arc "u" or "n?" What about to the East?
Thanks!

[Mark MacKenzie]

Just a heads up. It is the Earth that moves, not the stars...

As always, good to keep things in proper prospective.

[Vaughn]

Just a heads up. It is the Earth that moves, not the stars...

Of course. The sun will never set on the British Empire, nor the American. We'll just sit on it and rotate...

[Bruce Watson]

Just a heads up. It is the Earth that moves, not the stars...

The stars are not stationary; the stars are in fact moving, our sun included. But it is the motion of the earth that causes the vast majority of the motion recorded in star trails, yes.

[tgtaylor]

I've attempted to shoot star trails long ago with a 35mm and I'm tempted to try it with sheet film, but I have a question:
In N.America, how do I determine which way the star trails will arc? Pointing my camera to the North, will they arc "u" or "n?" What about to the East?
Thanks!

Like the sun (a star), stars "rise" in the east and "set" in the west which implies that the earth's rotation is in the opposite direction.



Which film will you be using? I've done quite a few star trails and wide field film on nebulae and our Milky Way using MF Pentax 67. Most negative colour films tend to be poor for colour and richness due to reciprocity. Provia 100F and Velvia 100F have give very nice results even at 90 minutes.

The best astro film is - was - Kodak E200. Great red Ha response - star colours and you could expose for hours. Made no more. Portra 400 new stuff - Ektar - have given muted colours, but the Portra may do better with a lens faster than f/4.

You can see some trails here www.pbase.com/pentax67 - in the Astronomy Gallery the various films.

Great astro photo's ivm. Thanks for the link.

As a side note, when Pentax re-engineered the P67 they specifically incorporated a power saving feature into the 67II for astrophotography to allow for long exposures without draining the expensive batteries.

Thomas

[ivm]

Great astro photo's ivm. Thanks for the link.

As a side note, when Pentax re-engineered the P67 they specifically incorporated a power saving feature into the 67II for astrophotography to allow for long exposures without draining the expensive batteries.

Thomas[/QUOTE]

Thank you Tomas - I use that feature a lot with my 67ii. I do night photography, and now astro with it, and many very long exposures. Over 100 rolls of film so far and 2 years of use on the same batteries. Push the power saving switch out - shutter to B - trip the shutter - no cable required - shut the camera off - push in power switch to end the exposure.

The older 67's (mark 2) work without batteries. There is small indent on the camera with a button switch inside. A bracket holds and positions a cable release over this hole. Depressing and locking the cable, you can do MLU - trip the shutter, and it will stay open regardless of shutter speed, until you release the cable.

[Mark MacKenzie]

Brilliant astrophotography, Ivan!

[Robert Brummitt]

Here is a print I have by Bruce Barnbaum, "Star Tracks, Matthes Crest".
From what I gather on the back, it was from a 4x5 neg, made in February 1992 .
Anyone know where Matthes Crest is?
I love the print it shows a planes flying light blinking and a satellite over head.
Cool stuff,
:) :) :)

[Marko]

Anyone know where Matthes Crest is?


Google thinks it's in Yosemite. :)

Here's one of the links (http://www.backpacker.com/may_2002_destinations_california_sierras_matthes_crest_climb/destinations/4345).

Marko

[Preston]

Anyone know where Matthes Crest is?

Definitely Yosemite-in the High Country above Tuolumne Meadows. It is located in the area of Cathedral Peak, Echo Peaks and Unicorn Peak. It is beautiful country!

The best access is up Budd Creek Trail to Cathedral Lake, or one can hike up to Elizabeth Lake and then go cross country, up past the Echo Peaks. Either way, the rewards are great!

--P

[Robert Brummitt]

Do you think Bruce pre focused and composed? I wonder if he saw how the stars play the night before?
Fun stuff!

[tgtaylor]

It looks to me that the photo was taken looking due north just west of Matthes Lake, about 1.5 - 2.0 miles cross country from the nearest trail. If you have a compass set to the proper declination, you can choose your foreground and compose during daylight pointing your camera due north to include Polaris as Bruce does in the picture. Polaris lies within a fraction of a degree of due north in the night sky.

Thomas