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Wednesday, August 17, 2011

Star Trails


I took this photograph from my back yard using the trees as a focal point.   I used a Nikon D200, with the Noise Reduction setting ON, ISO 200, Manual mode, f4.0, and BULB setting. Manual focus on the lens and camera.  The lens was a 17-55mm set at 17mm, with the hood on.  Tripod was a Gitzo 5541, with a modified quick release for the camera.  I used a Nikon DR-6  -  right angle viewfinder (so I don't have to lay on the ground to view).  I used the cap from a forstner bit (wood working drill bit) painted black, placed on the viewfinder, to prevent light from sneaking in from the viewfinder. A pop / soda bottle top could work too.  The remote was a programmable Nikon MC-36, set with a 4 second delay (to allow for mirror vibration), and 25 minute exposure.  I had an AC adapter for the camera attached to an added accessory, a battery backup I bought for jump starting a car in emergencies.  This would save my batteries since a 25 minute exposure will eat most of the battery on a D200.  Not to mention the noise reduction process afterward.  NOTE:  When setting the focus, DO NOT assume that infinity symbol on the lens is the end of the line.  I haven't found one yet that does that.  There will always be a bit of play in it.  During daylight, you can setup your shot, focus on infinity using autofocus, then shut it off.   Take note where that infinity symbol is in case it gets moved during the night.  The darker the sky, the better.  If you can find a place 50 miles away from the city, perfect.  This is sometimes impractical, since few people want to travel that far to take one, or two pictures. Closer to the city I prefer after midnight (closer to 2 - 3 am) photography, when some of the city lights are off when people go to bed. If there is light (moon, street lights etc) change the f-stop to something higher.   This photo was taken with f4.0 and turn out a bit too light so I changed the exposure in Photoshop to compensate.  Ideally, I should have had it set at f8 or f11.  Will try that next time.