star trails

question number one: how? do you have to havea cable release on bulband just hold it down a long time? can you use a wireless remote? i'm lost and curious. thanks in advance.

Restate your question - what problem are you trying to solve?

i want to take a picture of star trails and i don't know how

A cable release on bulb mode for however long. It will be a long time so get an ac adfapter for your camera so it doesnt die during the exposure. Also a good tripod and try not to do it in windy areas.

There are a couple of ways:


1. As mentioned, a cable release and a boatload of battery juice. A trail will start forming based on thefocal length. A longer focal length will show trails faster than a wide. Generally, the longer the exposuer thelonger and brighter thetrails.


2. Stack images. This is my preferred method.Instead of a single 45 min long expouser, take a series of smaller expousers of the same length and f stop (say2' at F8)and stackthem using Image Stacker or photoshop. If you have an interesting fore ground element, take a singlelonger exposuer, say 5' versus 2and blend that frame into the stack.


Makesure you have something interesting in the foreground. An egg timer helps with timing of expousers. Bring a book, caffinee, and warm clothes. In the northern hemisphere, the sky is better for starts in the dead of winter and not the height of summer. Having the NorthStar will cause full circles of trail and then arcs depending on how far the NS is away from the image.

Thanks! sounds like i should wait awhile since its about to be the summer

Check out this controler as you can program the number of exposures and the length of each one.


http://www.bhphotovideo.com/c/product/164271-REG/Canon_2477A002_Timer_Remote_Controller_TC_80N3.htm l

This is, to date, one of my favorite star trails pictures.


Teton National Park, with a Rebel XT, with my first and only wide angle lens (and still with me today), the 16-35mm f/2.8..


A single exposure with a full battery seemed to work fine. I hung out in the rental car while it was shooting. To the naked eye, there wasn't nearly so much light. I could barely see the mountain range after getting used to the dark for about 20 minutes. I used the cheap canon shutter release.


http://i110.photobucket.com/albums/n...e-800x1200.jpg



Shooting ModeManual Exposure
Tv( Shutter Speed )993
Av( Aperture Value )2.8
Metering ModeCenter-Weighted Average Metering
ISO Speed100
Lens16.0 - 35.0mm
Focal Length16.0mm

That's beautiful Colin!


Time to take some money out of the 70-200 f/2.8envelopeand get a remote shutter! hahah

do yo have to focus on the North Star first? also i am going on a trip in the open New mexico and was wondering(since it is soooo clear out there due to lack of civilization) if i could get a cable relase for my point and shoot. The G9 that im going to purchase. ??? help becasue i thought that would be amazing.