Amateur Astrophotography. Lauri Kangas Teekkarikamerat

Transcription

1 Amateur Astrophotography Lauri Kangas Teekkarikamerat

2 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

3 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

4 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

5 Deep sky objects Globular clusters Nebulae Open clusters Other galaxies

6 Solar system objects Sun Planets Moon Comets

7 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 (!)

8 Comparison of focal lengths 4.5 mm

9 Comparison of focal lengths 35 mm

10 Comparison of focal lengths 200 mm

11 Comparison of focal lengths 300 mm

12 Comparison of focal lengths 1250 mm

13 Comparison of focal lengths 3400 mm

14 Comparison of focal lengths 3900 mm

15 Comparison of focal lengths 4800 mm

16 Long exposures Deep sky objects are really dim Only a few photons per second Even ISO etc. can't magically make up light Long exposures necessary A remote shutter cable is needed Bulb exposures (30+ seconds) need a programmable timer

17 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.

18 Long exposures: Stacking Comparison of a single frame vs. stacked pic (10 min vs. 36 x 10 min)

19 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!

20 Fixed tripod astrophotos Star trails! Shoot a series of exposures 'Maximum' stacking Easily create stunning HD timelapse movies

21 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 mounts needed

22 Advanced astrophotography Autoguiding No <5000 mount is actually accurate enough for 60s+ exposures

23 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

24 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

25 Advanced astrophotography Cooled B&W CCD-cameras RGB filters Narrowband filters

26 Hard core astrophotography Computerized tracking mounts

27 Hard core astrophotography More computerized tracking mounts

28 Hard core astrophotography More computerized tracking mounts Better optics

29 Hard core astrophotography More computerized tracking mounts Better optics Bigger optics

30 Hard core astrophotography More computerized tracking mounts Better optics Bigger optics Motorized, temperaturecontrolled focusers

31 Hard core astrophotography More computerized tracking mounts Better optics Bigger optics Motorized, temperaturecontrolled focusers Dew heaters

32 HC out-of-control astrophotography Custom telescope sheds through the bedrock

33 HC out-of-control astrophotography Custom telescope sheds through the bedrock Remote control

34 HC out-of-control astrophotography Custom telescope sheds through the bedrock Remote control Observing villages

35 HC out-of-control astrophotography Custom telescope sheds through the bedrock Remote control Observing villages Fellow lunat.. observers

36 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

37 Have fun and keep it simple