Amateur Astrophotography Lauri Kangas Teekkarikamerat
Astrophotography Outline Introduction Knowing the sky objects to shoot Choosing equipment / focal lengths Long exposures Fixed tripod astrophotos Tracking mounts Advanced astrophotography Hard core out-of-control astrophotography
Introduction A natural extension of amateur astronomy Thrill of catching objects you normally can't see Very technically inclined branch of photography Doesn't have to be very expensive Always requires practice and preparation
Knowing the sky Most important part of astrophotography A variety of objects of different size and brightness Cartes du Ciel (left), Stellarium(.org), printed charts
Deep sky objects Globular clusters Nebulae Open clusters Other galaxies
Solar system objects Sun Planets Moon Comets
Choosing equipment DSLRs are powerful cameras for anyone to start with Busting myths: A telescope isn't necessary Any lens will do! The field-of-view determines what targets to choose Try out equipment you already own Try out equipment other people own (!)
Comparison of focal lengths 4.5 mm
Comparison of focal lengths 35 mm
Comparison of focal lengths 200 mm
Comparison of focal lengths 300 mm
Comparison of focal lengths 1250 mm
Comparison of focal lengths 3400 mm
Comparison of focal lengths 3900 mm
Comparison of focal lengths 4800 mm
Long exposures Deep sky objects are really dim Only a few photons per second Even ISO 25600 etc. can't magically make up light Long exposures necessary A remote shutter cable is needed Bulb exposures (30+ seconds) need a programmable timer
Long exposures: Stacking Digital cameras count photons A long exposure can be done in parts and summed together later Ruining one shot doesn't ruin the whole stack Kicking the tripod, airplane in front of target etc. Generally longer sub-exposures still better Busting myths: Noise is not an issue with long exposures.
Long exposures: Stacking Comparison of a single frame vs. stacked pic (10 min vs. 36 x 10 min)
Fixed tripod astrophotos Stuff that you can start doing right away Max exposure 2 to 60s before stars streak Catching satellites and meteors Aim at the Milky Way!
Fixed tripod astrophotos Star trails! Shoot a series of exposures 'Maximum' stacking Easily create stunning HD timelapse movies
Tracking mounts Mandatory for longer shots with pinpoint stars A motor turns the mount counteracting the star motion Simple and lightweight mounts at around 200 For telescopes, 1000 to 20000 mounts needed
Advanced astrophotography Autoguiding No <5000 mount is actually accurate enough for 60s+ exposures
Advanced astrophotography Autoguiding No <5000 mount is actually accurate enough for 60s+ exposures Another (small) lens and 100 camera is used to monitor a star
Advanced astrophotography Autoguiding No <5000 mount is actually accurate enough for 60s+ exposures Another (small) lens and 100 camera is used to monitor a star Small correction commands sent to the mount once / second
Advanced astrophotography Cooled B&W CCD-cameras RGB filters Narrowband filters
Hard core astrophotography Computerized tracking mounts
Hard core astrophotography More computerized tracking mounts
Hard core astrophotography More computerized tracking mounts Better optics
Hard core astrophotography More computerized tracking mounts Better optics Bigger optics
Hard core astrophotography More computerized tracking mounts Better optics Bigger optics Motorized, temperaturecontrolled focusers
Hard core astrophotography More computerized tracking mounts Better optics Bigger optics Motorized, temperaturecontrolled focusers Dew heaters
HC out-of-control astrophotography Custom telescope sheds through the bedrock
HC out-of-control astrophotography Custom telescope sheds through the bedrock Remote control
HC out-of-control astrophotography Custom telescope sheds through the bedrock Remote control Observing villages
HC out-of-control astrophotography Custom telescope sheds through the bedrock Remote control Observing villages Fellow lunat.. observers
HC out-of-control astrophotography Custom telescope sheds through the bedrock Remote control Observing villages Fellow lunat.. observers Inabilities to spend clear nights anywhere else than imaging
Have fun and keep it simple http://www.ursa.fi/~lkangas/