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Roman Kurywczak
02-18-2008, 06:34 PM
Basics of Star Trail Photography

(Scroll down for a sample image)


Equipment:

All you need for star trail photography is a fully charged camera with a bulb setting, a lens (wide angle preferably), sturdy tripod and head, a cable release that is able to be locked for at least an hour, bubble level for hot shoe, compass, and a powerful flashlight to aid in composition. Camera batteries vary, but I have gotten over 3 one hour exposures on a single charge, even on a very cold night.


Composing at night:
You really want to do this when there is no moon. To achieve star trail circles, you must find the North Star (or Southern Cross) and shoot with it in your frame. By far, the hardest part of night/astral photography is composing at night. One method is to scout a subject during the day, compose it, focus it, and mark your lens so that when you return at night, you are ready. This is not always practical but it can be done; http://www.birdphotographers.net/forums/showthread.php?t=3768 (http://www.birdphotographers.net/forums/showthread.php?t=3768)

New technology has made that much easier. I use a 10 million candle power flashlight that I purchased at Cabella’s for around $40. By pointing this light at the edges of your foreground subject, you can compose almost as easily as you would during the day. You can also use this to “paint” your subject if they are large or far away from you that a normal light can’t reach;
http://www.birdphotographers.net/forums/showthread.php?t=5335 (http://www.birdphotographers.net/forums/showthread.php?t=5335)<O:p

Remember that you don’t have to paint. You can have a silhouette with the stars trails.


Settings:
<O:pThe best starting point for star trails is ISO 100 and the next to widest opening on your lens (example; you have an f4 lens-set at 4.5) and the camera set to BULB. That’s it! You composed your image as to the instructions above, now lock the shutter open with the cable release. You can now begin your painting if you choose. Try to keep them open for at least an hour. The longer you keep the shutter open, the longer or full circle your trails will be. If you are pointing away from the North Star, your trails will be sideways or up and down.


These are just starting points. You can experiment with higher ISO’s; http://www.birdphotographers.net/forums/showthread.php?t=4976 (http://www.birdphotographers.net/forums/showthread.php?t=4976)
but remember that you start to introduce much more ambient light into the picture and that includes city light pollution!Precautions:<O:p
Night photography poses many challenges that daytime photography does not. I have on one headlamp while I’m walking and keep a spare in my backpack with extra batteries for both so as not to get stuck anywhere without a light source. If you are hiking around at night serious injury or worse can happen as uneven terrain is not as easily visible as it is during the day. Extra attention should be paid while walking around at night but it is well worth the reward.

The image below was created on my recent Arches trip. Canon Mark 3 with the 17-40mm lens at 17mm. Set at f4.5 for 1 hour and painted with flashlight.


See you in the night,
Roman Kurywczak
Small Group Photo Tours
www.roaminwithroman.com (http://www.roaminwithroman.com)

denise ippolito
11-30-2008, 10:56 AM
Really great advice-can't wait to try it!

Robert Amoruso
12-03-2008, 01:06 PM
Wow Roman - this is great.

HOW DID I MISS THIS?

Arthur Morris
12-07-2008, 08:27 PM
Cheeeeese. Just what I was looking for. Thanks bud. I knew that you were good for something besides Split ND filter recommendations.

Arthur Morris
12-08-2008, 05:14 AM
ps: How does one find the North star? Is it in the exact north?

Can you do just the star trails or do you need a foreground subject? (The star trails are spectacular on their own...)

Chris Ober
12-08-2008, 04:38 PM
If you can identify the Big Dipper (Ursa Major), the two end stars in the 'cup' form a line that point to Polaris. Polaris being the the end star in the handle of the Little Dipper (Ursa Minor). The Alaskan flag illustrates this too.
http://www.polar-sea.com/polar_sea/alaska_flag.jpg

Polaris isn't exactly true north but is slightly off from true celestial north and apears to rotate around it. It's close enough to true North though.


ps: How does one find the North star? Is it in the exact north?

Can you do just the star trails or do you need a foreground subject? (The star trails are spectacular on their own...)

Roman Kurywczak
12-08-2008, 04:53 PM
Cheeeeese. Just what I was looking for. Thanks bud. I knew that you were good for something besides Split ND filter recommendations.
Hey Artie,
You should have remembered :)..........you are the one who posted it for me in the Educational resources:D!
Star trails can be done on their own.......but FG.....even silhouette add a great deal. The longer you keep it open......the longer the circle.

I will still convince you of 4 ounces of split ND!

Thanks Chris for the N star....a compass will get you close enough........in the S hemishpere.........it is called the souther cross for the same effect.

Tony Whitehead
01-03-2009, 03:26 AM
I have recently read of (Practical Photography Nov 2008) but not yet tried a technique of setting the camera to continuous shooting, setting an exposure to achieve a clear star image at 30s and then triggering with a locking electronic release and continuing exposing for as long as you feel like. The result is a series of 30s exposures which you can then open as layers in PS and combine in lighten mode to reveal the trails. This can be combined with a dark frame for noise reduction and a frame exposed with lighting of the forefground/surroundings. The suggested advantage over the single long exposure is less sensor noise.

Roger Clark
01-08-2009, 12:50 AM
I have recently read of (Practical Photography Nov 2008) but not yet tried a technique of setting the camera to continuous shooting, setting an exposure to achieve a clear star image at 30s and then triggering with a locking electronic release and continuing exposing for as long as you feel like. The result is a series of 30s exposures which you can then open as layers in PS and combine in lighten mode to reveal the trails. This can be combined with a dark frame for noise reduction and a frame exposed with lighting of the forefground/surroundings. The suggested advantage over the single long exposure is less sensor noise.

Tony,
While stacking in general will improve noise by averaging, star trails, that must be combined by lighten or equivalent, result in enhanced noise. That is because each noise hit goes to increase the signal at that pixel, not average it. So far star trails, it is better to do longer exposures. If you are tracking and adding/averaging exposures, as in astrophotography, then shorter exposures are ok (but at dark sites people find several minute exposures still work best).

Roger

Alex Vargas
03-15-2009, 02:24 PM
Amazing... very interesting and just what I need to diversify a bit my galleries...
Thank you very much!

Alex