Amateur Digital : the affordable end of the spectrum

A practical guide on how to see beyond what meets the eye(piece) without being a zillionaire

Sculptor Galaxy (10.9 Million light years from earth). Image by: Chanan Greenberg

By Chanan Greenberg VP San Mateo County Astronomical Society Member of Fremont Peak Observatory Association & Peninsula Astronomical Society www.greenhawkobservatory.com

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(5(

Amateur Digital Astrophotography: the affordable end of the spectrum

A practical guide on how to see beyond what meets the eye(piece) without being a zillionaire

By Chanan Greenberg VP San Mateo County Astronomical Society Member of Fremont Peak Observatory Association & Peninsula Astronomical Society

sample images, and direction to additional data sources.

This series will include 4 segments: Part 1: Is Astrophotography for me? Part 2: Astrophotography 101: Shooting a Moving Target Part 3: Equipment: Mount, Camera, Focusing and Guiding Part 4: Imaging & Image Processing

Image Details: Chanan Greenberg 10" Newtonian, Orion Deep Space Pro 35 minute exposure Part 1: Is Astrophotography for me? This series of articles is designed to educate how to take exciting images of Astrophotography is technically planets, clusters, nebulae and galaxies. demanding, time consuming and People often find celestial photographs requires a long learning curve – in short breath-taking and believe that producing everyone can enjoy the pictures but such images can only be achieved by taking them may not be fun for some professionals and the wealthy. people. If you are just starting to develop your interests in astronomy the Over the last 3-5 years there has been a best advice I can offer is to stay away minor revolution in high quality, from astrophotography. The high affordable equipment that puts demand and little tolerance for in- astrophotography within reach of more accurate alignment and guiding may people than ever before. turn the fun and exciting hobby of to a nightmare of Whether you are an avid observer with a frustration and cause some to lose curiosity about astrophotography, if you interest in astronomy altogether. are thinking about taking a plunge into this space or a practicing If you are new to astronomy there are astrophotographer who is seeking tips many gratifying and easy things to do and tricks these articles will provide you before considering astrophotography: with guidance, tips, notes on equipment,

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(6(

• Learn the night sky, This is why I like going to our star constellations and stars parties at Crestview Park trying to find • Go to star parties and observe new objects I have never seen before through ; see what and often revisiting objects I have objects you can find viewed many times. Its also great fun to • Read about the objects you see share these night sky jewels with the • Go to planetarium shows public who love to look through the and learn more about what All these activities are fun, easy and their eyes can see. extremely rewarding and help build-up knowledge that will later be used in This leads to an interesting question – if astrophotography. observations can be so fun and breath taking images, taken by the Hubble If you enjoy looking at pictures of deep Space Telescope and other space space objects they are readily available observatories, are readily available by the thousands, on hundreds of online why bother with the hard work Internet Web sites. Its cheap, easy, no and expense involved with fancy equipment and you don’t risk astrophotography? losing extremities during cold nights. There is no correct answer to this Some people who delve into question - it is completely subjective and astrophotography never look through an will change from one person to the next. eyepiece again, while other “pure” observers have a disdain for The Interstellar Tourist astrophotography as they only want to For me the interest started simply with see what they can see through the the desire to share what I saw through eyepiece. the eyepiece with friends and family who did not come to star parties. Much like a Personally I am a hybrid. For years I did tourist who visits a special place, and pure observations with a Newtonian non though professional photographs are Go To scope finding objects using star available on postcards and in books maps, decent polar alignment and my they still take their own snap shot to say RA and DEC setting circles. This was a “Look where I have been, look what I great way to learn about the night sky saw”. and where objects are located. Words cannot describe the excitement I felt In a similar way I was so blown away by when I first laid eyes on M17. My polar views of the and its craters and alignment was inaccurate that night and fainter objects that I just had to capture the nebula did not appear in my those views and share them with others. eyepiece at first. As I slowly searched in And so on September 2003, I took a Fuji expanding circles suddenly this ghostly Digital Camera 2.0 MP, which is a very object came into view – M17 in all its simple regular digital camera, pressed it glory. My excitement knew no bounds against the eyepiece holding it as and it felt like I was the one who had steady as I could and took my first discovered it. image – the moon!

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(7(

let alone accept, defeat I kept looking for a way I could engage in this space.

The big change occurred with the introduction of a line of products that made astrophotography financially viable and in late 2006 I re-engaged and started investing little by little and started learning the art and science involved in astrophotography.

If at first you don’t succeed…… Destroy all evidence you ever tried. Or do as my mother told me and try, try, try again. Image Details: Chanan Greenberg 6" Newtonian, Fuji Camera 2.0 MB Auto Settings Astrophotography requires investing in

learning, acquiring skills, trial and error I was proud and excited about my first and lots of patience. Rarely do people successful shot and immediately started produce amazing images on day 1. wondering what other images I could Learning and improving on past take. I started experimenting trying to mistakes is key to a successful shoot planets, globular clusters and outcome. nebulae. Much to my dismay I rapidly discovered that even though I could see The Ring Progression wonderful views through the eyepiece This series of images of my digital camera was nowhere nearly M57, the Ring Nebula, as sensitive as my eyes and was unable illustrate my first to capture the details I could see. attempt of trying to

capture the image with Out of sight and out of pocket a regular digital camera Additionally, there were many objects I and the progress made heard about, read about but could never in equipment and see in the eyepiece and so I asked technique over time. myself how can I take images of objects

I cannot see? As I started asking around So, if seeing through I learned what astrophotographers used the eyepiece is not and how much it cost and reached the enough. If you feel a sad conclusion that astrophotography is need to be able to say probably not for me. "I took that picture" and

if you are not easily For a couple of years I just stuck to deterred by setbacks observing and occasionally trying my and love overcoming luck with my digital camera only to be technical disappointed all over again. challenges....well then

astrophotography might But there was a nagging feeling that I be just right for you! am missing out, that there is so much Carpe Noctem! more to see, combined with my own (Seize the night) disposition which never likes to admit, Next Part: Astrophotography 101 Shooting a Moving Target

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(8(

Part 2: Astrophotography 101 Shooting a Moving Target

Why is astrophotography so demanding? Why is it more difficult than just pointing the camera and taking a shot? Astrophotography has some similarities to shooting with any digital camera but it introduces some interesting twists that can make achieving a single good shot a daunting challenge.

As with taking a family snap shot with Image Details: Ring Nebula Chanan Greenberg 8" Newtonian, your digital camera, at the heart of the Orion Deep Space II Camera, 24 X 60 seconds exposure process is a Charged Coupled Device, One of the favorite deep space objects also known as a CCD chip. These chips amateur astronomers target is the Ring have a special characteristic – they are Nebula (M57). Many have seen this sensitive to light. More precisely they round puff of smoke in the eyepiece but react to a photon hitting the atoms that few have been able to see the central make up the chip and “excite electrons”. white dwarf that is giving off heat and When a photon hits a specific pixel on UV radiation making the gas around it the chip it is registered by the chip. The glow. The reason for this is simple; this more photons hit a pixel the brighter that white dwarf is thousands of times pixel will be. dimmer than the dimmest star you can see with the naked eye. Put differently, it This is the same process that occurs is not giving off much light. This is also when a digital image is captured no the reason that with the exception of matter what object you are shooting. very few objects most clusters, galaxies and nebulae appear to be grayscale to This is more or less where the similarity us and we cannot perceive their true between regular photography and color when observing through an astrophotography ends. In regular eyepiece. With the exception of a few photography the object you are very bright objects such as the moon photographing is rarely moving at and planets most objects are quite dim, hundreds of miles an hour and located way too dim for a regular digital camera trillions of miles away from you – this is to capture and represent well. To gather what astrophotography deals with. more light you need a telescope which collects and focuses light, a sensitive There are several challenges presented and preferably cooled CCD chip and the to us when we try to photograph ability to handle long exposures, i.e. celestial objects: allow enough photons to be collected, hit the chip and register as an image. • Limited amount of light • Motion of the Earth So now that we have established that • Earths Atmosphere long exposures, sometimes very long exposures, are required to collect enough light to produce an image we need to tackle the next challenge – shooting a moving target. Limited Amount of Light !"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(9(

Motion of the Earth: Polar alignment and Tracking

Over 4 billion years ago a massive object about the size of Mars collided with our planet tilting our axes of rotation. The Earth is rotating at a speed of over 900 miles an hour which causes the skies to appear to be moving from east to west. So as a night progresses objects that start out in the east will slowly move westward. Taking long exposures of objects in space is effectively trying to shoot a moving target which needs to be tracked. Sample images of poor tracking In order to track an object in the sky we must compensate for the Earth’s To take any exposure that is longer than rotation using a Right Ascension (RA) 20 seconds, accurate polar alignment tracking motor and properly Polar Align and good tracking is a pre-requisite to the scope along the axis of rotation acquiring good images. In fact, the best otherwise the tracking will not follow deep space camera on the market will accurately. Also, finding objects can still produce lousy results without a good become quite difficult. mount for tracking and good polar alignment. A middle of the road type of Most amateur astronomers who use camera can produce excellent results if equatorial mounts have become the mount is properly aligned and accustomed to handling polar alignment. tracking well. So the mount is where you Whether doing a rough visual alignment want to invest most of your dollars. or using a polar scope built into the mount, such an alignment is quite There are several methods to obtain sufficient for observing. Those who use good and even excellent polar a fork type mount rely on a 2-star or 3- alignment. The one most commonly star alignment and can easily find used is Drift Alignment which is an objects in the sky to observe. For iterative process of first tracking a star astrophotography this is not good near the intersection of the celestial enough. While the human eye and brain equator and the meridian and making are quite forgiving and will either not azimuth adjustments to your mount and detect or compensate for any tracking then tracking a star near the horizon and errors, a CCD chip is very unforgiving. making altitude adjustments to the While observing slight motions often go mount. When the stars stop drifting you un-noticed. A CCD chip however, are accurately aligned. faithfully records every photon hit and if tracking and alignment are not accurate Polar Alignment / Drift Alignment it will faithfully record every error making http://www.petesastrophotography.com/index.html? Select Drift Technique from the menu on the left to get images look blurry or even show an excellent step by step tutorial streaking star lines in the image.

Another method to align your scope is

using your CCD camera and software !"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(:( like PoleAlignMax which automatically experience. This is why auto-guiding is measures how far off you are from the so helpful. Auto guiding does essentially actual pole and helps you in the process the same thing, a second CCD camera of achieving very accurate polar tracks a specific star and when it drifts alignment. by more than a preset distance (often less than 0.3 pixels) the camera will PoleAlignMax http://users.bsdwebsolutions.com/~larryweber/PoleAlig send a correction action to the mount. nMaxDownload.htm There are various ways to handle auto- guiding from dual chip cameras, to off- Getting good polar alignment is a matter axis guiding cameras to having a of repeated efforts and as time goes by completely separate camera and scope you will get better at it. Don’t despair it is used for guiding. time well invested which makes finding very dim objects easier and reduces In summary to be able to produce high tracking errors significantly which helps quality images you need to be: produce better images. • Polar Aligned • Tracking well using PEC Now that you are polar aligned you can • Auto-guiding tackle the next task – accurate tracking. While most RA motors can track objects Earth’s Atmosphere quite well for observational purposes no Now you are ready to focus and start motor is perfect and inconsistencies in imaging and process your images. the gears will cause objects to move just enough to potentially ruin a nice image. But there is one more challenging factor – Earth’s atmosphere. Imaging objects To deal with this issue better mounts in space through Earth’s atmosphere is offer a feature known as Periodic Error like taking images from the bottom of a Correction (PEC). Basically, you run a pool. The atmosphere is filled with warm training session in which you use a high and cold air streams, pollutants, water magnification illuminated eyepiece to vapor and numerous other components track a star and keep it centered using that can make life quite difficult for the RA control buttons. The mount astrophotography. A petition to have the records the actions you take to correct Earth’s atmosphere removed has been the tracking and uses these corrections rejected on the grounds that it is as part of its standard tracking process required to sustain life – even the life of compensating for any built-in errors it astrophotographers. The two main may have. factors that impact our ability to take images through our atmosphere are While PEC can produce excellent Transparency and Seeing. results and is strongly recommended, even that alone will not be enough for really long exposures. This leads us into There are some solutions that introduce guiding and specifically auto-guiding. adaptive optics which compensates for changes in the atmosphere these come Guiding used to mean that the with an added cost, so most astronomer would have to be next to the astrophotographers keep hoping for scope and look through an eyepiece at good conditions. a guiding star and manually make adjustments to correct any tracking errors during the exposures. That can It is important to understand that bad be a very demanding and uncomfortable Seeing will effect your ability to focus

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(;( your camera and can sometime even sites very often need to learn how deal sabotage your guiding efforts. Really with the annoying pain of light pollution bad seeing will cause your focus point to that waters down your image, drowning move in and out making some parts of it in light and killing contrast. There are your exposure seem out of focus and in ways to combat light pollution which we some case will make stars appear to be will be presented later in this series. moving causing your auto-guider to send correction commands to your Astrophotography 101 summary: mount chasing phantom motions of the star. 1. Gather as much light as you can – translates into generous aperture, a Best way to overcome this issue - pick a cooled CCD chip and long exposures good night for imaging. One cool tool to 2. Accurately polar align help you do that is Weather Ninja 3. Track well with PEC and Auto-guiding available at: 4. Pick a good night and choose a good http://www.ccdware.com/Files/weatherni location if you can nja15.zip Before you dash out to buy equipment why not first pay a visit to Jazz Under the Stars at CSM where you can get first hand experience at imaging under the guidance of Dean Drumheller or come to one of SMCAS star parties at Crestview Park and ask for people’s advice.

Next Part: Equipment: Mount CCD Camera, Focusing & Guiding

Screen shot from Weather Ninja Carpe Noctem! (Seize the night) Weather Forecasting for Astronomers http://cleardarksky.com/csk/ http://www.intellicast.com Although not designed for astronomy its Dew Point information tends to be accurate and useful

Last but not least: location, location, location. Where you choose to do your imaging has a huge impact on the length of exposures you will need, the post imaging processing and overall quality of your images.

Dark skies are THE BEST. However, Part 3: Equipment: Mount, CCD many of us who live in light polluted Camera, Focusing & Guiding areas and cannot get out to dark sky

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(<(

This chapter will cover what you should exposure of a 1 hour image that consider when selecting equipment. The whole image may be lost and whole objective of this series of articles that hour is wasted. If you were is to provide a practical guide on how to taking 6 ten minute exposures create an affordable imaging setup. That one of them may be lost but the said these are all relative terms. For combined 50 minutes can still be some of us living in a light polluted used. environment is a fact of life we need to 2. While the best results are deal with while for others going often to derived from long exposures locations with dark skies is a practical there is another practical option. Affordability is also something consideration that limits how quite relative. So my assumption is that long we should expose which is the reader is likely to be working in a light pollution. When a CCD light polluted area. If you are not, all the Camera is exposing it collects advice is just as valid and your life will light – all light - including that be easier. Additionally at the end of this orange haze we see in the sky in chapter I have provided a check list on light polluted areas. That light how to build what I consider to be a waters down the image and good imaging system. reduces contrast and is difficult to remove. In heavily light Important Clarification: I am openly polluted areas, an exposure that biased towards equipment provided by goes much longer than 2 Orion Telescopes. This is my main minutes, will cause the CCD chip frame of reference and is what has to over-saturate by light worked for me. In my opinion they offer pollution. You can still achieve the best balance between cost and good results, just by taking many performance and the quality of customer shorter exposures and then service I have received has been combine them. beyond reproach, especially from the Cupertino store. I wanted to make it clear that I am not compensated in any way by Orion and am merely expressing an opinion based on my experience.

My equipment comments will extend to other vendors such as SBIG, Meade and others.

How long does 'long' mean? Throughout these articles I have referred to taking long exposures. Some images require hours of exposure. Image Details: M42 Chanan Greenberg Orion 10” Newtonian, However, it is common practice to take Orion Deep Space Pro. 9 X 2 minute exposures taken under a series of shorter exposures (sub- light polluted skies frames) 1 to 10 minutes long and stack them during the image processing stage. There are a few good reasons to follow this practice: 1. Planes & Satellites can often fly Selecting a Mount through the field of view you are As mentioned in a previous chapter, the imaging. If you're in mid mount is the place you want to invest

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(=( the majority of your budget. The best 5. Auto-Guiding – the mount needs telescope with the best camera will still to have a port designed to deliver poor results if mounted on a accept auto-guiding commands mount that does not perform well. The 6. Computer Control – you will key features you want to make sure you spend a significant amount of mount can handle are: time at your computer during an 1. Equatorial Vs Fork – most imaging session, the ability to people that I know who do control the mount through the imaging use an computer is going to make your as it is best designed to mimic life significantly easier and make the motions of the sky. This does your session more productive not mean you cannot do imaging 7. GO-TO – while not a must, you with a fork mount and some fork can find targets using setting models from both Celestron and circles and star maps, it is a Meade offer auto-guiding huge efficiency gain and is capabilities. My recommendation absolutely required if you plan to leans towards the equatorial use automated processes like design especially for long PoleAlignMax to refine your exposure sessions. polar alignment 2. Weight Limit – you have to make 8. GPS – definitely a nice to have sure that your mount is capable gadget but not a must. The GPS of handling the weight you plan feeds in the correct time, to put on it. If you overload the coordinates and altitude mount you increase the chance information into to your mount’s of ruining the gears and it will hand controller instead of you strain to keep up with your having to do it every time. tracking demands. Your weight 9. Budget – mounts that offer this limit will vary depending on the entire scope of abilities start at setup you create. A camera with $700 and go as high as $70,000 a dual-chip setup which can self- (yes that is $70,000). There are guide with a small refractor, very good mounts such as which is a great setup for wide Losmandy, Celestron CGE, field imaging, can way less than Vixen Atlux and Vixen SXD all 20 lbs. While a large scope, with retailing from $3,000 to $5,000 a secondary guiding scope and 2 which perform well and can carry cameras can weigh more than a heavy load. Since we are 50 lbs. focusing on affordability the most 3. Quality of Motors – make sure cost effective investment I have your mount has high quality seen to-date, is the Orion Atlas dual-axis motors allowing it to EQ-G. track in both RA and DEC. There are many mounts out there that will claim to do a great job but few that actually meet the demanding accuracy required for imaging. 4. PEC Capability – the ability to train the mount on how to compensate for periodic errors Leveling and Balancing your Mount

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(5>(

Regardless of which mount you select, DSLR cameras and produce very leveling your mount and balancing are impressive results. DSLR cameras critical for good imaging. probably out-perform many small chip and cheap astrophotography CCD A non leveled scope means that even if cameras. I have very limited experience you are properly polar aligned and your using DSLR cameras for tracking is accurate you will experience astrophotography. Overall a true deteriorating tracking during your dedicated camera for astrophotography session as you are not truly tracking in should give better performance when RA. Most mounts have a built in bubble used with cooling. that makes leveling the mount an easy and fast task. The key considerations when selecting A non balanced mount means that your a camera: mount is heavier on one axis. This will 1. Camera / Scope combination – press your gears tighter against each different chip sizes and scopes other when pointing the scope in one with different apertures and focal direction and may cause them not to lengths create different imaging mesh well when pointing in another systems which impact the type of direction. Overall this strains the motors, objects you can image and the unhealthy for the gears and will make field of view you have. As a rule your tracking and guiding efforts more the smaller the chip and the difficult. larger the aperture of the scope the more limited the field of view will be and the higher the magnification. Larger chip and small aperture produce wide fields of view and lower magnification. Additionally, the scope’s focal length is a determining factor impacting exposure time. For 2 scopes of the same aperture but different focal lengths, the shorter focal length will require shorter exposures. 2. Sensitivity – different chips used by different manufacturers have different levels of sensitivity and other related parameters. Quantum efficiency basically is a good indicator for how sensitive the chip is. Generally the more sensitive the better. The Kodak

The Orion Atlas EQ-G Mount chips used in SBIG cameras boasts an 85% quantum efficiency. Old Orion cameras Selecting a CCD Camera using Sony made chips had 60% Let me start by making a quick note quantum efficiency, the new about DSLR cameras. I have seen Orion cameras also use Kodak some astrophotographers use various chips. Full-well capacity is !"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(55(

another parameter. Each pixel wheel and filters. They also on the chip has a full-well require more processing work capacity, after a certain amount after imaging is done. For a of photons have hit that pixel it similar sized chip it can be said can no longer “contain” them and that Monochrome provides spills over to adjacent pixel higher resolution as the entire making them bright too. chip is used for each type of 3. Cooling – cooling the chip below exposure while the One Shot ambient temperature is very Color uses a Bayer filter and effective in reducing the amount offers lower resolution. of ‘noise’ the camera detects and 6. Software Support – make sure the less noise will make its way your camera works with one of into your image. Additionally, the following software packages: some cameras not only cool the CCDSoft, or MaxIm DL or MaxIm chip but allow you to set the DL Essentials, or Nebulosity. Its temperature the chip is cooled not just that these are good to. This is very helpful when application but there is a large imaging over several days and community of users who have using Dark Frames when it is formed user groups on the important to make sure the Internet that can provide lots of images are being captured by advice and feedback the chip at the same 7. Guiding Cameras – some temperature. imaging cameras have a built in 4. Blooming Vs Anti-Blooming – second chip that is used for blooming is what happens with guiding (AKA self guiding). the full-well capacity is exceeded These tend to be available in the and adjacent pixels appear higher priced cameras. Other bright to the point that a star is alternatives are dedicated burnt out and lines appear in the guiding cameras such as Orion’s image. Some cameras ‘bloom’ Auto-guider or using a second while others introduce a cut-off imager that is not dedicated to point that prevents blooming. guiding. While some will say it is Generally, anti-blooming critical to use a monochrome camera’s are less sensitive and camera for guiding, I used a One require longer exposures than Shot Color camera for guiding blooming cameras. with very good results. 5. One Shot Color Vs Monochrome 8. Solar System Vs Deep Space – – generally speaking solar system objects are Monochrome cameras (that significantly brighter than deep shoot in “black and white” and space objects. The image of the use filters to capture color moon below is a 0.08 second information) typically produce exposure while deep space superior results to One Shot objects require many minutes to Color imagers. That said, they start showing up in the image. take at least double the time to There are some cameras that capture the same image as each are less sensitive and designed exposure requires 4 sets of for solar system imaging; they exposure (Luminance, Red, are also moderately priced – well Green and Blue) and they are below $200. more expensive as in addition to the camera you need a filter

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(56(

large format cooled chip cameras in the market retailing below $2K. Most comparable cameras cost more.

Image Details: Chanan Greenberg 0.08 Second exposure of the moon Orion StarShoot Solar System 9. Budget - it's surprising how many vendors and how many models of astronomy CCD cameras are available. Vendors such as StarlightXPress, FLI, Apogee and the very well respected SBIG provide high quality cameras ranging from $2,000 to $35,000. There are other vendors such as the Meade DSI product line but frankly in my limited experience they do not

match up in comparison to the vendors listed above or to the Orion StarShoot Deep Space Pro Orion product line of cameras. As this series of articles is titled "the affordable end of the spectrum" I have focused on what I believe provides the highest quality within a reasonable level of expense. After doing my own survey of the market to select which products I invest in I selected the Orion StarShoot product line which offers: • Solar System camera • Deep Space Camera III • Deep Space Camera Pro Orion Parsec • Parsec Series

The Orion StarShoot Deep Space Pro cameras and the Orion Parsec cameras offer, in my opinion the best balance of !"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(57(

focuser but also track temperature changes allowing you to adapt your focus point during an imaging session. Orion’s AccuFocus works very well and is quite affordable.

Focus Controller – a control box that allows your computer to communicate directly with the Electronic Focuser so you can control the focuser from your computer. Shoestring Astronomy provides FCUSB which works very well and supports a wide range of focusers.

Imaging Software – such as CCDSoft and MaxIm DL that can show you as you focus the Full Width Half Maximum (FWHM) and Half Flux Diameter (HFD) numbers. Using the software you can focus “by the numbers” as you bring down both HFD and FWHM numbers the closer you are to being in focus. Its always a good idea to go beyond the Image Details: Lagoon Nebula (M8), Trifid Nebula (M20) and Open Cluster M21 Chanan Greenberg Orion 80mm APO optimal focus point and work your way Refractor, Orion Deep Space Pro. 15 X 2 minute exposures and 5 X 3 minute exposures back then you know you are at the optimal focus point Focusing This is probably one of the hardest tasks FocusMax Software – this free software in astrophotography that requires the completely automates your focusing most practice until fully mastered. efforts. It initially does an analysis of the Imaging dim objects sometimes objects optical performance of your system. It that you cannot really see presents an then takes over the camera and focuser interesting challenge – how to focus the and automatically brings you into the image. best focus point it can find.

The simplest way is to set your camera on continuous exposures while pointing the scope at a bright star and bringing it into focus. This manual process requires time to master and is rarely accurate.

A combination of hardware and software can help you focus quickly and accurately:

Electronic Focuser – a motor attached to your focuser allowing you to move the focuser position without touching the scope. There are several excellent

Electronic Focusers like JMI that not Orion AccuFocus only control the movement of the !"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(58(

and your done. The application will do all the rest of the work for you and has delivered excellent performance.

Software There is some software you need to have and lots of software that is nice to have. The following list includes all the software I use and I mention some Shoestring Astronomy FCUSB alternatives, there are 13 software

packages listed, 9 are available for Guiding FREE and only 4 cost money: The process of guiding and auto-guiding was touched on earlier, and additional New Astronomy CCDCalc – this practical tips on how to achieve good application is a great tool which is guiding will be covered in the next part available free from Ron Wodaski’s web about Imaging and Image Processing. In site (http://www.newastro.com/). Ron’s this part focused on equipment I will just book “New CCD Astronomy” is highly say this: almost any descent CCD recommended and provides great detail camera and scope can provide good and guidance on astrophotography. This enough guiding. I often use my 80mm application allows you to create any APO Refractor as a guiding scope. You combination of telescope and camera do not need an APO refractor to do and see the resolution of the system in guiding; there are good guiding scopes arc seconds per pixel and see your field available for under $300. For a while I of view overlaid on top of an actual used one of my deep space cameras image of many targets. This tool is great from Orion as my guider camera for planning imaging sessions although it was not design to be used as a guiding camera it worked very well. I Polar Finder – this is a nice little currently use Orion's StarShoot application also available for free Autoguider. Some people try and use (http://www.polarfinder.co.uk/) which CCD camera’s designed for solar simply shows you where Polaris should system imaging and try those for guiding be in your polar scope. It’s a fast way to mostly with no success as those validate your initial polar alignment is cameras are not sensitive enough. close

I know of some people who use simple ASCOM Platform – ASCOM platform is webcams as their guiding camera who free and it is a standard protocol for claim to achieve good results. astronomy allowing software to control

various types of equipment ranging from Guiding Software – almost any mounts, cameras, to guiders and commercial application designed for focusers imaging such as MaxIm DL and

CCDSoft support controlling a second Starry Night Pro – is a planetarium guiding camera and guiding routines package that simulates the night sky, it including calibration and tracking. I allows you to find objects and get huge personally prefer using PHD Guiding amounts of information about almost which is free and is literally a point and any object. This application also click solution. You connect your provides cool tools such as field of view equipment, start exposing, select a star which allows you to setup any

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(59( combination of scope, camera, eyepiece required for correcting your polar and Barlow and see exactly what your alignment errors. field of view would look like which is very helpful in planning imaging PHD Guiding – I use this for auto- sessions. It also can control the mount guiding. Simply works great and is free and you can send your scope to any (http://www.stark- object directly from your desktop. An labs.com/phdguiding.html) alternative to Starry Night Pro is The Sky which offers excellent options and is CCD Stack – wonderful software that considered an excellent software handles image stacking and processing. package. In my opinion it is the fastest way to good results. FocusMax – already reviewed earlier in this chapter. This application automates Photoshop – final retouching, non-linear your focusing process and is available stretching of an image’s histogram and for free. where certain filters can be used to clean up images. PoleAlignMax - already reviewed earlier in this chapter. This application Weather Ninja – free software to help automates the process of correcting you assess if weather conditions will be your polar alignment and is available for favorable for imaging free. Virtual Moon Atlas Pro – this free MaxIm DL Essentials – this software software provides incredible detailed comes bundled with Orion Deep Space maps and images of the moon, helps cameras. It handles imaging, auto- learn about the moon and about each guiding and image processing crater. It is the perfect companion for a night of lunar observing MaxIm DL 5 – I use this version of MaxIm although I got the Essentials version for free with my Orion Cameras. Assembling a complete imaging I prefer the full version as it offers a lot system more tools for planning image sequences, batch processes that So what does is it take to assemble a automate many commands and its good imaging system from scratch: support of Pin Point astrometry which is

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(5:(

Item Comments Orion Atlas EQ-G GoTo Mount Orion 10” Newtonian You can pick the astrograph version of you want a dedicated system Orion Guiding Scope Alternatively you can use off-axis guiding Orion StarShoot Deep Space Pro Large format CCD camera or Orion Parsec Orion StarShoot Autoguider Orion Sky Glow Filter for Imaging Orion AccuFocuser Shoestring Astronomy FOCUSB Shoestring Astronomy GUSB Starry Night Pro MaxIm DL Essentials Bundled with Orion Cameras MaxIm DL full version Optional CCD Stack Optional Photoshop Optional PHD Guiding Free FocusMax Free PoleAlignMax Free GPS Unit for Mount Optional

The entire list above can be purchased for less than $5,000.

Until a few years ago just a good camera could easily cost $3,000 and up to $15,000 dollars for the camera alone!!

For those who wish to shave off more money off this budget check out sales opportunities and Clearance sales on Orion (www.telescope.com) and Scope City's (www.scopecity.com) web sites as well as Astromart.com and Cloudynights.com - you can reduce this budget by 20-30% if you are willing to use second hand equipment

Next Part: Imaging and Image Processing Carpe Noctem! (Seize the night)

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(5;(

Part 4: Imaging & Image I recommend either drift alignment Processing method or using PoleAlignMax which were described in chapter 2. This This last installment about amateur process of adjusting your azimuth and astrophotography is focused on altitude to get as close as possible to providing practical guidance on how to the true pole can take 15 to 45 minutes capture and process images to produce based on experience and some luck. pleasing results. While this is a time consuming process it will make for a better imaging session At the end of this chapter is a list of links and is worth the investment. to additional information on all the topics that were covered in these articles. Star Alignment This is the same process you would do Imaging for an observation session, using 2 or 3 This section will describe the steps I star alignment to allow your scope to follow in an imaging session, which are: find its bearings and be able to accurately point to your desired object. • Plan Make sure that tracking or tracking with • Setup PEC is turned on. • Improve Polar Alignment • Star Alignment Focus • Focus Find a star that is 3 to 5 magnitude and • Slew to Object center it. Using your focuser controls • Start Guiding move the camera in or out and watch • Imaging what happens to the FWHM and HFD numbers. Make sure your camera is on Plan – think about what objects are continuous exposure mode exposing an going to be visible and which ones you image every second or so. If your want capture. Use CCDCalc or Starry camera supports sub-frames draw a Night to see what your field of view will rectangle around the star you are be when looking at these objects with focusing on and the images will your scope and camera combination so download much faster from your you can plan what orientation your camera. After each change you make to camera may need to be in, in order to the focuser allow for 3 -4 exposures to capture the image. Spending some time determine if this made things better or planning your session allows you to be worse as minor vibrations from the more effective during your session. motion of the focuser tube and slight changes in seeing may impact the Setup – if you are fortunate enough to results of a single exposure. Keep have a permanent setup you can skip making changes until you can bring the this section: numbers of FWHM to below 4 and HFD • Rough polar alignment below 3. These numbers will produce • Balance scope decent focus. If your have very good • Check collimation (important for seeing you might be able to get the Newtonian scopes) numbers down to 2 which is very good • Install all cables, control boxes for focus. Using the free FocusMax focusers and guider application can effectively automate the entire process for you.

Improve Polar Alignment Slew to Object !"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(5<(

Using your select the full version of MaxIm DL you can the object you wish to image and slew easily setup an Imaging Sequence, the scope to that object. If it is a very instructing MaxIm DL to take 20 2 dim object try taking a few sample minute exposures and 10 3 minute exposures increasing their time until you exposures etc and it will execute for you can see the object you are looking for is automatically saving the images in a in fact located in your field of view. If folder you designate. When you are at needed make minor adjustments in RA this phase it is pretty much an auto pilot and DEC to place the object where you situation but its always a good idea to want it to be in the final image. keep track of what is going on. I always try to take several types if images Star Guiding ranging from 300 seconds and up to 15 Using PHD guiding establish a minutes to see what produces the best connection to your guiding camera and results. I use the Orion StarShoot Deep to the mount. Start capturing images, try Space Pro camera which is a One Shot 2-3 second exposures and see if you color camera. So when imaging it is can find a reasonably bright star to use important to make sure the output is set for guiding. Click on the star and a to raw or monochrome. These images green rectangle will appear around the contain color data but you currently star. Click the stop button and then click cannot see it. Do not try to shoot directly on the Guide button – lean back and in color it will produce poor results. enjoy the show. PHD Guiding will conduct a calibration process slewing A useful tool to combat light pollution is the scope West, East, North and South Orion’s Sky Glow Filter or the IDAS measuring the distance the star moves. equivalent for Imaging. Unlike regular Once done it will start guiding. broadband filters available from Orion, Congratulations if your scope is well Lumicon and many other vendors that aligned you should get rock solid block out sodium spectrum lines they guiding. also block out quite a bit of red light, this filter was designed specifically for Imaging imaging and lets a lot more red data get So this is what all the fuss is through while still doing a good job about….you are now ready to start reducing the effects of light pollution. imaging! When imaging you should take into account the nature of the object Other exposures your are trying to capture, its brightness In addition to the Light exposures you and the light pollution situation as well will want to do 3 more types of as seeing conditions. Under certain exposures. Dark Frames, Flat Field and conditions a 2 minute exposure may Bias these will be used in image look better than a 3 minute exposure processing to reduce various types of that got oversaturated with light pollution noise from your image. You can think – so experiment and see what produces about it this way: the best results. In principal longer exposures produce better results. In Dark frames capture ambient noise and other words a 10 minute exposure hot pixels your camera might be should look better than 5 X 2 minute capturing even when no light is going exposures. BUT, this rules works well into the camera. It is recommended you under dark skies, in light polluted areas take the dark frames at a similar CCD chips get oversaturated quickly temperature as the light exposures and and so combining shorter exposures will that you take a few to create an average produce better results. If you are using that can be subtracted from the light

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(5=( frames later. You should make sure that MaxIm will automatically identify the for each light exposure length you have dark frames. several dark frames with the same exposure length. IMPORTANT NOTE: since some processes may have undesired results it Flat fields – is the way to capture ‘noise’ is always a best practice never to work or dirt on your optics and have those on your original images. Make a copy of subtracted from the image. It is also your images and apply the following required to remove vignette effects of steps to this copy. If mistakes occur or shooting with a rectangular chip through you don’t like the outcome, you can a round tube. Flat fields are an image always make another copy of your taken of an evenly illuminated object like original images and start over. the twilight sky or dawn sky. Since they are not easy to take some people build Next open all the images you wish to a light box to create an evenly process in MaxIm DL and select illuminated view. Calibrate All from the Process menu. All the noise captured in the dark frames Bias frame – is the level of ‘noise’ the will be subtracted from the light frames. chip may see when no or limited current Save all the light frames that were goes through it. calibrated. In CCDStack you need to follow the instructions in the software. Image Processing TIP: in my experience it is worthwhile Congratulations!! You now have a series take the Flat field master and applying a of images taken including light and dark Boxcar filter to it in MaxIm DL before frames. For the purposes of this subtracting it from the Light Frame - this explanation I will assume the images tends to produce smoother results. were taken with a One Shot Color CCD camera. The steps in processing the Convert to Color images are: Open the images you just calibrated in MaxIm DL and select Convert to Color • Calibrate from the Color Menu. Make sure your • Convert to color camera brand is selected in the Camera • Register drop down menu and click OK. If you • Normalize have many images you can automate • Reject Data this process using MaxIm DL’s batch • Stack command mode. Save your color • De-saturate background converted images. In CCDStack the • Digital Development (DDP) Convert to Color command allows you • Noise Ninja to select different methods supporting • Unsharp Mask monochrome as well as different Bayer Filter layouts. Calibrate Calibration is the process of subtracting Register Dark, Bias and Flat field data from your You can continue the process in MaxIm Light frames. It can be done in MaxIm that offers powerful stacking tools. I DL and in CCDStack. I prefer have grown accustomed and I like using CCDStack. In MaxIm DL select Set CCDStack. Where you first select Calibration from the Process Menu. Register from the Stack Menu to select Select the folder where you have saved stars used to align images before they your files and click on Auto Generate. get stacked.

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(6>(

This process which is available in Normalize MaxIm DL and in Photoshop helps This processes in CCDStackstarts with improve the sharpness of an image. It the reference image and analyzes all effectively creates a blurred version of the other images and defines what the image and then subtracts that from weight to give them when stacking the the image creating a sharper image. images. Beware no to overdo it or you will create a sharp but grainy image. Reject Data This option in CCDStack provides Imaging the Horeshead Nebula several procedures that allow you to systematically remove noise and This section will walk you through the artifacts from your images before they various stages with sample images so are stacked. you get an idea of what to expect.

Stack This image is of the Horeshead Nebula This is the final step in stacking images. and Flame Nebula in the Orion There are several types of methods to Constellation. stacking. You should experiment and see what works well. In my experience Technical Data: selecting Mean or Sum produces the Date: October 22, 2008 best results. Telescope: Orion 10" Newtonian Imaging Camera: Orion StarShoot Deep De-saturation Space Pro From my backyard in light-drenched Guiding Scope: Orion 80mm APO silicon valley this is a step that helps Refractor reduce the impact of light pollution. I run Guide Camera: Orion StarShoot Deep the Adjust Color / De-saturate Space Camera background option and most of the light Mount: Orion Atlas EQ-G pollution data which appears green 10 X 120 second exposure when using a broadband filter is 5 X 300 second exposure removed. MaxIm DL 5 PHD Guiding Digital Development (DDP) CCD Stack Is a method of reducing background Photoshop information while enhancing fine details in nebulae and galaxies Image 1 Raw Data: this is one 300 second exposure. You may notice poor Noise Ninja contrast, no color, there are some black This is an optional step. If previous diagonal lines going through the image processes have produced a grainy (result of slow communication USB) and image, there is a filter that can work a satellite line streaking through the independently or within Photoshop that image just to the right of the horsehead. helps smooth out grainy areas in your image which is a very good alternative to Gaussian Blur which does the same thing but also blurs the image a little

UnSharp

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(65(

Image 2: Calibrated and Color Convert Image 4: Background Color Saturation & The image below is the same image DDP after calibration and color conversion The image below is the final result of adjusting color saturation, flattening the background and Digital Development.

Image 3: Stacked Image The image below is the final result of registration, normalizing, data rejection and stacking - note all noises and Image 5: Final Image artifacts have been removed. The image The image below is the final result of is drenched in light pollution cleaning up the image from grains using

Noise Ninja.

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(66(

Orion's Web site www.telescope.com

Scope City's web site www.scopecity.com

Stark-Labs (Nebulosity & PHD Guiding) http://tech.groups.yahoo.com/group/star k-labs-astronomy-software/

http://www.stark- labs.com/phdguiding.html

Starry Night This brings this chapter and this series http://www.starrynightstore.com/stniso.h about astrophotography to an end. This tml is by no means a comprehensive overview. For those interested in how http://tech.groups.yahoo.com/group/Star it's done it should give a good idea. And ryNight/ for those looking for tips on how to get started it provides good information. I SBIG would encourage those interested, to http://www.sbig.com/ deepen your education through the data sources listed below CCD Stack http://www.ccdware.com/ Carpe Noctem! (Seize the night) MaxIm DL List of additional Data Resources http://www.cyanogen.com/help/maximdl/ MaxIm-DL.htm Ron Wodaski's New CCD Astronomy - this book can teach you everything you http://www.cyanogen.com/help/maximdl/ need to know MaxIm-DL.htm http://www.newastro.com/ Pin Point Astrometry CCDCalc Application http://pinpoint.dc3.com/ http://www.newastro.com/downloads/ind ex.php

Sample photos on my Website http://www.greenhawkobservatory.com

Orion StarShoot User Group http://tech.groups.yahoo.com/group/Orio n_StarShoot/

Atlas EQ-G User Group http://tech.groups.yahoo.com/group/EQ 6/

!"#$%&'(!)$'*+,*$*-'#+,./(0,#1#1(2'%%13%'-( 4#-%(67(