Scott Butner http://www.scottbutner.com/ Photographing the Night Sky Richland Public Library Lecture November 15, 2012 Scott Butner http://www.scottbutner.com/
What I’ll Cover Introduction What you’ll need to take night sky photos Some camera basics Shoot the moon! Shooting the stars and the milky way Catch a falling star The northern lights? In Washington?! Useful resources
Introduction
What you’ll need
Essential equipment A camera with the following: Manual control A [wide angle] lens of f/2.8 or faster Usable ISO of 1600 or higher Remote release or self timer Tripod Flashlight Backup flashlight Appropriate clothing
Scouting locations Scouting locations ahead of time is VERY important Finding safe parking/ingress/egress and noting hazards Finding good terrestrial objects Noting power lines, road signs, other easy to miss visual impediments Take notes! Note mileposts, landmarks, etc.
Finding dark skies Dark skies are increasingly hard to find in our region Typically need 30-40 miles from medium sized metro area to find reasonably dark skies Clouds, dust, haze will exacerbate this Localized light sources can often be incorporated or obscured
A few words about safety Think ahead for safety! Park well off the road Scout ahead if possible Wear “safe shoes” Always have a backup light Be aware of your surroundings
Some camera basics
The Bucket of Light ISO Shutter speed f/stop
ISO – How big is the bucket? ISO is a measure of how sensitive the camera is to light The higher the number, the less light is needed But high ISO ratings also generate more noise (grain) ISO 3200 ISO 400 ISO 200
f/stop – How big is the hose? f/stop is a ratio between the lens opening and focal length The smaller the number, the more light it allows in For most night photography, wide f/stops (f/1.4-f/2.8) are essential Typical f/stops: f/2.0 f/2.8 f/4 f/5.6 f/8 f/11 f/16 f/22
Shutter speed – How long does the water flow? Shutter speeds tell us how long the camera allows light to hit the film/sensor MOST night photography requires long exposures (> 1 second) Photographing the moon is a big exception
Putting them together Different combinations of ISO, f/stop and shutter speed produce the same amount of light – but not necessarily the same results 3200 ISO @ f/4, 30 sec 3200 ISO @ f/1.4, 4 sec 1600 ISO @ f/2.8, 30 sec
Some “typical” exposures Milky way, rich star field 1600 ISO, 30 sec @ f/2 Bright stars, planets 1600 ISO, 15 sec @ f/2-2.8 Moon Full: 200 ISO, 1/500 sec @ f/8 Half 200 ISO, 1/125 sec @ f/8 Crescent (highly variable!) Lightning 400 ISO, f/5.6-8, timed for flash*
Shooting the moon
Tips for shooting the moon The moon is both the easiest and the toughest of night sky objects to shoot Highly variable (but predictable) brightness Very narrow range of opportunities to capture “optimal” shots Dramatic “big moon” photos require big lenses
Shooting the stars and milky way
General night sky tips In general, find the darkest, “cleanest” skies you can – not easy these days! Be aware of moon phases. Too much moonlight hurts Clouds can be good picture elements but amplify any light issues Try to include some foreground elements for scale, dramatic relief
Tips for photographing stars Modern cameras can disclose detail you’d never see with naked eye Find the sweet spot for getting point-like stars Very wide or fisheye lenses – 30 sec Moderate wide angle – 20 sec “normal” lens – 10 sec or less Apparent motion greater as you move away from celestial pole
Making star trails
Making star trails Star trails can provide a dramatic way of showing the earth’s motion But long exposures demand a very dark sky! 7-10 minutes is about the shortest exposure that makes sense Effect varies with focal length and distance from celestial pole StarTrails software can greatly simplify the job!
Photographing meteors
Tips for shooting meteors Frequency of meteors is less important than brightness/duration Lyrids, Taurids both known for producing bright fireballs Use the highest ISO, widest f/stop you can muster Be sure field of view extends 20-30 degrees beyond the radiant Best strategy is to use lots of moderately long exposures and hope for the best
Key meteor showers Orionids – THIS WEEKEND! Geminids – December 13-14, 2012 Quadrantids – January 3-4, 2013 Lyrids – April 21-22, 2013 * Perseids – August 12-13, 2013 * Orionids – October 20-24, 2013 Taurids -- Nov 4-6, 2013 Leonids – November 17-18, 2013 *
Northern Lights
Tips for northern lights (aurora) Northern lights are not common in our area, but do occur several times/year Usually prefaced by 24-48 hours of warning Require a very dark northern horizon Exposures comparable to that for milky way (e.g., 20-30 sec, f/2.8, ISO 3200) Can disclose detail not seen by naked eye
Next year’s comet Comet ISON due to be visible in late 2013 Projected to be brighter than full moon, visible during daylight hours Potential for a once in a lifetime sight! Photo of Comet Lovejoy by Luis Argerich Used under Creative Commons http://www.flickr.com/photos/lrargerich/7394541294/
Some handy resources Handy apps Web sites TPE (The Photographer’s Emphemaris) Moon Phase calendar StarTrails.exe Web sites http://www.wunderground.com/radar/radblast.asp?ID=PDT&type=N0R http://www.gi.alaska.edu/AuroraForecast/NorthAmerica/2012/11/13 http://www.skyandtelescope.com/observing/ataglance http://www.spaceweather.com/
Scott Butner’s Flickr Site For more pictures…. Scott Butner’s Flickr Site http://www.flickr.com/rs_butner/