Astrophotography 101

How I Started or - One Fool’s Mistakes Meade video eyepiece Meade video eyepiece Visual Visual Video Capture - Video Capture - Still image creation Still image creation Video Camcorder Video Camcorder Registax - free Registax - free

How I Started - Continued Stellacam II Stellacam II

How I Started - Continued What is possible? What is possible?

StellaCam II Images Lunar 1 Sinus Iridium

StellaCam II Images Lunar 2 Crater Clacius

StellaCam II Images Lunar 3 Copernicus

StellaCam II Images M31

StellaCam II Images M42

StellaCam II Images M42 Mosaic

Versus CCD Image of M42

StellaCam II Images M82

Versus CCD Image of M82

StellaCam II Images Eskimo Nebula – NGC 2392

Lessons Learned Don’t Do It! Don’t Do It! There are more things to There are more things to learn = challenges = problems learn = challenges = problems than you could ever imagine! than you could ever imagine! You can forget ever being able to afford retirement! You can forget ever being able to afford retirement! But … if you love it But … if you love it Then Go For It Then Go For It

First Lesson Learned Your mount is the most important single piece of equipment Your mount is the most important single piece of equipment Buy the best quality you can afford Buy the best quality you can afford If you must go with one of the less stable mounts consider "wide field imaging" = more arcseconds/pixel. You can accomplish this by either If you must go with one of the less stable mounts consider "wide field imaging" = more arcseconds/pixel. You can accomplish this by either using a lower r-ratio scope such as Richard's Epsilon f/2.3 using a lower r-ratio scope such as Richard's Epsilon f/2.3 using a bigger chip with more pixels - DSLR is an effective way to do this using a bigger chip with more pixels - DSLR is an effective way to do this Or both Or both You will be a lot happier and get good results You will be a lot happier and get good results This is key to Richard’s early success - in my opinion This is key to Richard’s early success - in my opinion

Second Lesson Learned I can’t emphasize enough how important it is to I can’t emphasize enough how important it is to FOCUS, FOCUS, FOCUS FOCUS, FOCUS, FOCUS We all try to do it manually We all try to do it manually Then we try gadgets Then we try gadgets Then we buy computer controlled automated focusing systems & life is good again! Then we buy computer controlled automated focusing systems & life is good again! Save time & just skip the first 2 steps Save time & just skip the first 2 steps

The Key Imaging Principle: Noise

There are photons everywhere! Trouble is, you don't want ALL of them!

Noise – It’s Not Your Friend Taking an image is a game of chances Taking an image is a game of chances Noise is a mathematical concept, but in essence Noise is a mathematical concept, but in essence “Noise in an image is the uncertainty in the brightness level.” Ron Wodaski “Noise in an image is the uncertainty in the brightness level.” Ron Wodaski You get a photon – is it really from your target = signal … or is it junk = noise? You get a photon – is it really from your target = signal … or is it junk = noise? Signal/Noise = S/N ratio Signal/Noise = S/N ratio electrons from object/ electrons from noise electrons from object/ electrons from noise This concept is This concept is central to astrophotographic imaging central to astrophotographic imaging the driver of many of our image manipulations the driver of many of our image manipulations

Sources of Astrophotographic Noise Sky Noise Sky Noise light pollution - human light pollution - human also gradients also gradients Celestial – “the evil orb” Celestial – “the evil orb” also gradients also gradients Errant objects Errant objects Geese Geese Airplanes Airplanes

Sources of Astrophotographic Noise Continued Errant objects Errant objects Satellites Satellites Space station/shuttle Space station/shuttle Meteors Meteors Asteroids Asteroids

Sources of Astrophotographic Noise Continued Cosmic Rays Cosmic Rays

Sources of Astrophotographic Noise Camera noise Camera noise thermal noise thermal noise read noise read noise blooming blooming Dark Frame degrees

Sources of Astrophotographic Noise Camera noise Camera noise blooming blooming Blooms on single 10 minute exposure

Sources of Astrophotographic Noise Tracking Tracking Poor polar alignment Poor polar alignment Periodic error Periodic error Guiding errors Guiding errors Optical noise Optical noise Dust motes Dust motes Vignetting Vignetting Atmosphere Atmosphere Seeing Seeing Transparency Transparency

Time Is On My Side

Overcoming Noise Long exposures increase signal/noise because signal increases faster than noise Long exposures increase signal/noise because signal increases faster than noise Combining several exposures Combining several exposures is like adding more time, is like adding more time, but at the price of some small increase in noise but at the price of some small increase in noise Time is on our side Time is on our side Dark skies increase S/N ratio because the lower sky background means less “noise” Dark skies increase S/N ratio because the lower sky background means less “noise”

Overcoming Noise How do you overcome the noise? How do you overcome the noise? Dark Skies Dark Skies Camera cooling – decreases thermal noise Camera cooling – decreases thermal noise Dark subtraction Dark subtraction Flat field correction Flat field correction Combining images = averaging Combining images = averaging Deblooming Deblooming Artifact removal Artifact removal

Overcoming Noise – Raw Single Frame

Overcoming Noise - Calibrated

Overcoming Noise - Debloomed

Overcoming Noise – Combine 18 frames (100 min.)

Overcoming Noise – M81 Final

Resources Equipment Equipment GEM mount vs. Alt – Az Mount (rotator) – barn door mount GEM mount vs. Alt – Az Mount (rotator) – barn door mount OTA – f-ratio OTA – f-ratio Camera Camera Video – Webcam (planetary) vs. Mallincam or StellaCam – (deep sky) Video – Webcam (planetary) vs. Mallincam or StellaCam – (deep sky) DSLR – Huetech modified DSLR – Huetech modified Internal vs. external guiding Internal vs. external guiding NABG vs. anti-blooming NABG vs. anti-blooming color vs. monochrome color vs. monochrome Filters Filters Computer – graphics/image processing horsepower Computer – graphics/image processing horsepower Monitor for graphics – Eizo vs. Dell vs. Apple Monitor for graphics – Eizo vs. Dell vs. Apple Consider Pantone colorvision Spyder Consider Pantone colorvision Spyder Software Software Image capture – Maxim vs. CCDSoft Image capture – Maxim vs. CCDSoft Stacking – Maxim vs. API4Win vs. CCDStack vs. Deep Sky Stacker Stacking – Maxim vs. API4Win vs. CCDStack vs. Deep Sky Stacker Image Processing – Adobe PhotoShop CS2 Image Processing – Adobe PhotoShop CS2 Add-ons – Noise reduction, Noise Ninja vs. Neat Image vs. Kodak Digital GEM Add-ons – Noise reduction, Noise Ninja vs. Neat Image vs. Kodak Digital GEM Astronomy Tools - selected programmed image manipulations Astronomy Tools - selected programmed image manipulations

Resources Books Books Adam Block’s DVD series Adam Block’s DVD series Making Every Pixel Count from Caelum Observatory Making Every Pixel Count from Caelum Observatory Ron Wodaski Ron Wodaski The New CCD Astronomy The New CCD Astronomy The Zone System for Astro Imaging The Zone System for Astro Imaging Berry & Burnell Berry & Burnell The Handbook of Astronomical Image Processing The Handbook of Astronomical Image Processing The Bible for Imagers – can I hear, Amen? The Bible for Imagers – can I hear, Amen? Networking Networking Internet sites too numerous to list Internet sites too numerous to list Imaging groups Imaging groups Yahoo has groups for almost every interest Yahoo has groups for almost every interest Cloudy Nights Cloudy Nights Contact individuals off-line for help Contact individuals off-line for help

The MI-250 Mount

The Imaging Train

The Imaging Train Labelled

The Dark Horse Observatory