Astrophotography, believe it or not… …is not as hard as rocket science. It’s not rocket science. • • • • • • • No Physics degree required No Computer Science degree required No Engineering degree required Some computer skills can be useful Some mechanical ability is useful A basic understanding of electronics is useful Some understanding of the underlying science is a great plus • While equipment continues to improve, the core technology itself is reasonably mature – it is highly unlikely that you will need to invent anything in order to be successful • Patience and perseverance are absolutely mandatory! It’s not black magic, either. It’s not black magic. understanding the critical elements involved leads to better results a little simple math can greatly assist in understanding how things work as well as what you might expect as a result using practical and measurable considerations when making equipment choices will ultimately simplify the job taking the time to develop a logical and tested workflow will improve your odds of repeatable results How Solar System Imaging differs from Deep Sky Imaging • most objects are generally much brighter than DSO’s • good results can be achieved at relatively fast shutter speeds • highly effective cameras are generally much less expensive than purpose-built astronomical CCD cameras • accurate tracking is not as critical to success – guiding is completely unnecessary • good results can be had using moderately priced telescopes and mountings with uncomplicated setups • trips to dark sky are not required in order to get good results How Solar System Imaging differs from Deep Sky Imaging • the details we are trying to capture are generally much smaller in apparent size than DSO’s longer focal length instruments are useful for best results telextenders (“powermate”, barlow and/or extension tubes) are very helpful in increasing image scale • larger aperture instruments help overcome light loss due to the high focal ratios involved • much more susceptible to poor seeing, focus and collimation Cameras Solar System Cameras Philips ToUcam Pro 740K • No longer in production but widely available used on the Web on eBay and AstroMart • Can be bought ready to go for astrophotos for $50.00 or less • Uses Sony ICX098BQ CCD chip • Has 640x480 array with 5.6µm pixels • Works best at 5 to 15 frames per second Solar System Cameras Phillips SPC-900NC • No longer in production but still available brand new from eBay and used from eBay and AstroMart • Cost to make this camera ready for astrophotos is generally under $75.00 • Uses Sony ICX098BQ CCD chip • Has 640x480 array with 5.6µm pixels • Works best at 5 to 15 frames per second Solar System Cameras Celestron NexImage • Commercially produced imager based on the Phillips ToUcam design • Available at major astronomy and photographic shops as well as on Amazon.com for under $100.00 • Uses Sony ICX098BQ CCD chip • Has 640x480 array with 5.6µm pixels • Works best at 5 to 15 frames per second Solar System Cameras StarShoot Solar System Imager III • Commercially produced imager using 1.3 megapixel CMOS chip • Priced at $189.95 at Orion Telescopes • Comes bundled with MaximDL Essentials software • Uses Micron MT9M001 CMOS chip • Has 1280x1024 array with 5.2µm pixels • Maximum frame rate of 15 frames per second Solar System Cameras SAC Systems Model 7b Imager • Commercially produced modified webcam with Peltier cooling and long exposure capability • No longer in production, but available used on websites like AstroMart for generally less than $200.00 • Specs vary per production run but all imagers have 640x480 CCD chips Solar System Cameras DV Camcorder (aka – the camera that you already have) • Lower TCO by using a camera you already have • Conversion for astro use is not permanent and can cost as little as $30.00 • Fixed lens requires that images be taken using afocal photography rather than prime focus photography Tips for Afocal Photography • Use an eyepiece with long eye relief • Couple the end of the camera lens as close as possible to the eye lens of the telescope eyepiece • If possible, set the digital camera at macro mode rather than infinity • Use full optical zoom, but do not use digital zoom • If possible, use a camera lens with a focal length longer than the eyepiece focal length Solar System Cameras Imaging Source DMK 21AU04.AS • Commercial camera originally designed for industrial applications • monochrome but available in a color model • Suggested retail price $390.00 but can be had for less at certain retailers • Uses Sony ICX098BL CCD chip • Has 640x480 array with 5.6µm pixels • Has a maximum frame rate of 60 frames per second using firewire port, but this USB model performs better at 30 fps on my laptop Solar System Cameras Luminera SkyNyx 2.0 • Commercially produced camera specifically for astrophotography, this is the entry level model for this line • Monochome and color versions available • Retail price $995.00 • Uses Sony ICX424 chip • Has 640x480 array with 7.4µm pixels • Maximum frame rate is > 100 frames per second Solar System Cameras Dragonfly Express • • • • • • By Point Grey Research Industrial firewire camera – Point Grey is just beginning to cater to the astronomy market Monochrome and color versions available Suggested Retail price is $1195.00 Uses Kodak KAI-0340DM/C CCD chip Has 640x480 array with 7.4µm pixels Has maximum frame rate of 350 frames per second Software Image Scale 3777mm efl @ f/18 5846mm efl @ f/25 6342mm efl @ f/23 8416mm efl @ f/24 13,149mm efl @f/40 So – how does this work in practice? Image Scale – Prime Focus Image Scale – Prime Focus Image Scale – 2X Barlow Image Scale – 2X Barlow Hey, wait a minute… Hey, wait a minute… • If the line is 72 pixels long at prime focus, shouldn’t the line be 144 pixels long with the 2X Barlow? Hey, wait a minute… • If the line is 72 pixels long at prime focus, shouldn’t the line be 144 pixels long with the 2X Barlow? • No. The actual magnification of a barlow is determined by how far the imaging chip is from the last lens in the barlow. Hey, wait a minute… • If the line is 72 pixels long at prime focus, shouldn’t the line be 144 pixels long with the 2X Barlow? • No. The actual magnification of a barlow is determined by how far the imaging chip is from the last lens in the barlow. • This behavior gives us some interesting options for increasing the image scale in our Solar system images! Televue Barlow Magnification Image Scale – Barlow w/extension Image Scale – Barlow w/extension So – what did we get? • 72 Pixels represents “1X” – baseline • With the “2X” barlow in place, the line went to 176 pixels – in actuality, my “2X” barlow is really a “2.44…X” barlow – an over achiever to be sure • Adding 36.76mm of extension to the optical train took the line to 228 pixels, giving us a total increase in scale of 3.2X over the native scale – increase this extension and you increase the scale! What’s Next? • • • • • How some easy math provides answers to questions you need to know: How big will Jupiter be on *my* telescope? How long *was* my effective focal length? What *was* the focal ratio of the system? How long can I expose Jupiter before the planet’s rotation causes smearing? Yes, I will talk about capture and processing too!