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How To Guide: Astrophotography with a DSLR Photography Gear , Photography Gear Tips & Tricks Add comments Jul112012 Getting started in Astrophotography is easier than you think but mastering it will take a life time. This is a guide for beginners or people with a small amount of experience. I’ll be focusing on taking pictures with nothing but DSLR cameras and regular lenses. No telescope required! The only other piece of equipment you will need is a tripod. If you have another type of digital camera with a “manual” setting you can still follow along though some of the options I talk about may not be available to you. Later on I will go into some other pieces of gear you can buy that will further enhance your ability to take pictures. Finally we will talk about how to process your images in Photoshop as most of the time the image straight from the camera is a bit underwhelming. All the pictures featured in the article were taken by me with a DSLR (either Nikon D300 or Nikon D700).

How To Guide: Astrophotography with a DSLR

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Page 1: How To Guide: Astrophotography with a DSLR

How To Guide: Astrophotography with a DSLR Photography Gear, Photography Gear Tips & Tricks Add comments

Jul112012

Getting started in Astrophotography is easier than you think but mastering it will take a life time. This is a guide for beginners or people with a small amount of experience. I’ll be focusing on taking pictures with nothing but DSLR cameras and regular lenses. No telescope required! The only other piece of equipment you will need is a tripod. If you have another type of digital camera with a “manual” setting you can still follow along though some of the options I talk about may not be available to you. Later on I will go into some other pieces of gear you can buy that will further enhance your ability to take pictures. Finally we will talk about how to process your images in Photoshop as most of the time the image straight from the camera is a bit underwhelming. All the pictures featured in the article were taken by me with a DSLR (either Nikon D300 or Nikon D700).

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Milky Way – Nikon D700, 105mm f/3.5, 8x2min,

ISO 3200

Choosing A Camera Any Digital SLR camera should be enough to get you started. If you are looking for a specific camera to buy for this purpose, Canon’s are the most popular for astrophotography but Nikon’s also do fine. The most important reasons for using a DSLR are the large sensor (for better signal to noise ratio), the ability to keep the shutter open as long as you want and the ability to shoot RAW files. This makes full-frame DSLR’s even better because their sensor is larger than regular DSLR cameras. The last basic piece of equipment you need is a tripod.

Did you know? Some DSLRs can be modified specifically for Astrophotography use. While DSLRs are fine for photographing stars, galaxies, and reflection nebula their weak point is emission nebula because they have an built-in filter to block out certain wavelengths of light. By removing this filter or replacing it with clear glass you can improve the sensitivity for hydrogen-alpha light. One company that will do this to your camera, or sell you a pre-modded one is Hutech. Canon has even released a DSLR specifically for this purpose known as the Canon EOS 60Da. The benefit of that is you still get a full manufacturers warranty. The downside? This mucks up the color balance of regular daytime shots, so it is not the best option unless you want to use that DSLR solely for Astrophotography.

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Other helpful equipment • Shutter release cable isn’t absolutely necessary but highly recommended.

You can by cheap third-party ones on ebay instead of paying for a genuine one.

• Anti-fog cloth can help with condensation that builds up on your lens under certain atmospheric conditions at night time. If your lens keeps fogging up this might help.

• Red flashlight to see what you are doing out in the dark. Using a regular flash light will harm your night vision but red light won’t.

• A sky tracking mount to take exposures longer than 30 seconds or so. This requires an extra investment so I recommend trying other methods first. I will talk about trackers later.

• A comfortable chair (you will be waiting a lot) and extra warm clothes if its winter time.

• Binoculars to enjoy the view while pictures are being taken or to maybe pick out your next target.

Nikon D700, 24mm f/3.5, 120 seconds, ISO 1600 single exposure

Choosing A Location Some types of Astrophotography are doable in the middle of the city but that tends to be limited to lunar or planetary photography. Planetary photography requires a telescope but if you have a telephoto lens of at least 300mm or so

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you can get some nice shots of the moon. Photographing deep sky objects or getting a lot of stars in your image is not very doable in the middle of a city. The good news is just driving for 15 minutes outside of city limits can really improve the sky quality.

I want to shoot… Location

The Moon All you need is a clear sky! This can be done right in the middle of a city.

Night-time landscapes (Starscapes)

Starscapes are shots where the landscape is mostly lit by the moon (or stars at exceptionally dark locations) and you will need moderately dark skies for this. Think Suburbs or darker.

Wide-field shots or Constellations

You can get away with doing some of the brighter constellations inside a medium size city as long as you are sheltered from city lights by trees or buildings but outside the city will be best.

Star Trails

About the same as Constellations, but as with any Astrophoto the darker the sky the better. If you want to do very long single exposures you need a true dark sky site, but if you plan on stacking many shorter exposures you have a lot more flexibility.

The Milky Way

For this it is ideal to be at least 30 miles/50km away from any city or town. You can get away with being closer to the city if the milky way is in the sky opposite the nearest city. For the absolute best milky way images you need to be many hours away from any cities.

Galaxies and Deep-Sky objects

The requirements are the similar to Milky Way shots; rural skies or better. Some objects will photography decently even in suburban skies. Some of the bigger objects like Andromeda Galaxy and Orion Nebula can be done with a telephoto lens but you will still need a tracker of some kind to move your camera with the motion of the sky.

Light Pollution

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Light pollution is caused by stray man-made light that is aimed at the sky. The main problem for astronomers is it washes out the sky and reduces the amount of stars and deep-sky objects you can see and/or photograph. Aside from the aesthetic problem of the nasty orange haze in the sky instead of stars, light pollution is an incredible waste of energy. Why do we need to light up the sky? If all the light from street lights and outdoor lights was aimed at the ground with proper shades above them to reflect ALL of the light to the ground, you would be able to use lower power lights. Lighting up the sky is akin to leaving all your windows and doors open while you leave your furnace on in the winter. A complete and utter waste of energy. You can find more information at the International Dark Sky Association. If you live in the USA or parts of Canada you can see how the light pollution is where you live by going to the Dark Sky Finder site. You can also get a good idea of where you would have to go to get dark skies. For other countries if you Google your country name along with “light pollution map” you should hopefully have some luck in finding one.

Beginner Shots

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In this part we are going to cover all types of shots that can be taken with your DSLR without a tracking mount – moon shots, starscapes & widefield shots, star trails and milky way wide shots.

Guide Navigation Introduction & The Basics | Beginner Shots | Advanced Shots | Photoshop Processing

Lunar Eclipse & Saturn – Nikon D300, 240mm, f/6.3, 0.3 seconds, ISO 1600 single exposure

Moon Shots The above shot of the February 20th, 2008 lunar eclipse was taken just with a 70-300mm lens and a tripod – nothing fancy. That brightest point of light on the left side is actually Saturn. A view like this wouldn’t have been possible with a telescope. While close ups of the moon are great you can get interesting shots like this with just a telephoto lens.

Focusing can be tough in Astrophotography but moon shots are the exception. My suggestion is to use your camera to autofocus on the moon and then set it to manual focus and be careful not to adjust the focus. Even though the moon is bright and you can use a fast shutter speed you still need to minimize camera vibrations. If you don’t have a remote shutter cable to trip you should use the self timer mode on your camera to take shots. Something like 3 or 5 seconds is enough for vibrations to dissipate. You will want to use manual

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exposure mode for the moon as auto exposure will overexpose it usually. Here are some recommended settings to try:

Full moon: f/8, 1/640, ISO 200 Half-moon: f/8, 1/500, ISO 400 The above are only starting points. Exposure time will change with the moon’s position in the sky and other factors. You want it to be bright but be careful not to overexpose the brightest edge. Below are some ideas for other types of shots you can take of the moon (click to enlarge). The first one is showing off the “earthshine” on the moon’s surface. The overexposed part is what you are normally seeing the the dim part is normally cloaked in shadow but with a long exposure you can see the shadowed section of the moon dimly lit by the earth’s reflected light. The other one is a stylized picture of the moon in some clouds.

Starscapes and Wide-field shots

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Starscape over a camp fire – Nikon D700, 24mm, f/4, 60 seconds, ISO 1600 single exposure

Starscapes are probably my favorite type of shot to take. In the above shot I was looking forward to taking some milky way shots but the clouds rolled in as you can see. While they would have ruined the shots I planned on taking they arguably enhanced this one. What I just said is tantamount to blasphemy though. Clouds are the arch-nemesis of any astronomer!

Focus: The first thing you need to do is focus on the stars. There are many ways to do this but you may struggle your first few times – don’t get discouraged. If you have an older style lens (the ones that usually have an f-stop ring right on the lens) those lenses typically have a hard infinity focus stop so they are the easiest; focus to infinity and you are done. This is probably why my 2 favorite astrophotography lenses are my 24mm f2.8 Nikon prime and 50mm f1.8 Nikon prime. More modern DSLR lenses usually don’t have a hard infinity focus point though so you may need to do some trial and error. If your lens doesn’t have a hard infinity focus point: See if your camera will autofocus on a bright star (or the moon if its out). If it does, great! Once its autofocused switch the focus to manual and be careful not to adjust it. If your camera fails to autofocus, put it in live-view mode on

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your tripod and point it at the brightest star (or moon if available). See if you can focus on the live view mode. If not, manual focus as best as you can in your viewfinder then take a test shot. To make it quick, use a high ISO like 3200 and take a 5 or 10 second picture and check the stars. Keep fine tuning your focus til the stars are solid points of light. They are out of focus if the center is dimmer than the outside. Exposure: The first thing you want to do is stop your lens down at least 1 stop to improve the quality of stars and reduce vignetting. If the max aperture for your focal length is say f/3.5, try using something like f/5. If you are in moderately dark skies (rural, out of the city) try taking a shot with a 30 second shutter speed and ISO 1600. Most DSLRs max shutter speed is 30 seconds and to go longer you need to use “BULB” mode. So for longer than 30 seconds you need a remote shutter cable to keep the shutter open (bulb keeps it open as long as its pressed – you can’t do this with your hand or your shot would be a blurry mess). If you have a newer model camera you can probably get away with ISO 3200 to double your light. Other settings: Disable any camera noise reduction settings. You are better off doing your noise reduction in post. If you don’t want to get too advanced with post processing, you can leave “long exposure noise reduction” on. What this setting does is take a second picture but with the mirror down so no light can hit the sensor. This is called a dark frame. Then the camera automatically subtracts it from your shot to reduce dark current noise and hot pixels. Personally I prefer taking my own dark frames and subtracting them myself as necessary…plus that way I can take multiple dark frames. Dark Frames?: It’s a good idea to take these if you had long exposure noise reduction turned off in your camera… you may need them later in processing. To take a dark frame, put your lens cap on and take pictures using the same settings you did with the lens cap off (only ISO and shutter speed is important). The most crucial thing is to take them in an environment with the same temperature as your regular pictures since temperature affects the noise. I usually take my

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dark frames while I am packing up all my stuff at the end of the night. So if your shots were 30 seconds, ISO 1600 take a few dark frames at those settings.

Other Starscape examples (click to enlarge)

Star Trails

Star trails in black and white – Nikon D700, 24mm, f/4, 6x11min exposures stacked (66min), ISO 640 Star trails are one of the most popular types of Astrophotography. It’s hard to perceive the movement of the sky due to the earth’s rotation unless you are

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looking through a high power telescope and then you can watch an object pass across the field of view in a matter of seconds. The longer your lens, the longer your star trails. Using a wide angle lens it takes around 20-30 seconds for trailing to become apparent but with a 300mm lens it happens in less than 5 seconds. There are 2 methods of taking star trails which means you can take them in virtually any environment except metropolitan.

Getting Ready You will need to achieve proper focus as described in the above “Starscapes” section and make sure your camera’s battery is fully charged (bring a spare if you can). If you are going to use the stacking method things will go easier if you camera has an intervalometer or you buy a remote shutter cable that can be programmed to take shots at specific intervals such as the Canon TC80N3 or Nikon MC-36. There are also cheaper third party models on eBay that also work for more camera models (Nikon remotes and Canon remotes). Look for the ones with the little LCD screens. Regardless of what method you use, you don’t want to leave your lens wide open. It’s best to stop down at least 2 full stops so you get sharper stars across the whole image. If you are rocking $2000 glass I suppose you can ignore my suggestion. If your max aperture for the focal length you chose is say f/3.5, try shooting somewhere between f/5.6 – f/8.

Single Exposure Method With this method you just take one extremely long exposure. Anywhere from a few minutes to hours! There are some strict requirements for being able to do this method though. The first one is there can’t be any moon in the sky. It will end up overexposing not only your sky but also any landscape your happen to have in your shot. The only exception being you can sometimes manage shots under 30 minutes if you use ISO 100. The second requirement is extremely dark skies. If you are within ~100 miles of any city or town, forget about doing that hour long exposure you were thinking about – the light pollution will wash out the sky and your stars. Cameras can drain battery fast when they leave the shutter open. It will vary from camera to camera but you

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may need to use a power adapter for your camera instead of a battery. Finally, some cameras will just have a finite amount of times that they can keep their shutter open (and thus their CCD or CMOS amplified) before “amp glow” becomes an issue. Amp glow is caused by heat in the camera and usually starts at the edges of the image and gets worse. If you are taking pictures in cold temperatures you might avoid it all together. Picking the right exposure settings can be tricky. If you let in too much light, your picture will get washed out and overexposed. If you let in too little, fainter stars may never get a chance to register on the sensor because they have moved before they were able to expose. In most cases you will want to use ISO 100 or ISO 200 depending on your f-stop and exposure length. You can test out how many stars you will get by taking a shorter exposure of say around 5 minutes. Any trails you see there will be the exact same trails you see on longer exposures, only they will stretch longer. One setting you can try first is this: f/5.6, ISO 100, 30 min (1800 sec) shutter speed. By using that as a baseline you can see if your sky is too bright or too dark, if your landscape is exposed properly, if there is any amp glow, etc. The single exposure method requires a lot of trial and error but if done properly results in some very otherworldly looking images.

Stacking Method With this method you have a lot more flexibility. You can do this in moderately light polluted environments and when the moon is out as well. The basic idea is instead of taking one single 60 minute exposure you would instead take 60 separate 1 minute exposures and stack them to make it look like a single continuous star trail. You don’t want to have more than a second in between shots or else the gaps between images will be too large. You can use exposures with higher ISOs to gather more stars compared to the single exposure method. It’s quite simple; find the exposure setting you want for your picture and by taking multiples of that same exposure and stacking them, the star trails will grow and nothing else in the image will change. I will discuss this again in the processing section of this guide, but the basic method to stack in Photoshop is to load up all your frames into separate layers

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and set all the layers to the “Lighten” blending mode. Better yet, there is a fantastic little program called Startrails that does this for you and also lets you load in dark frames. You can download it here at Startrails.de.

More Star Trails examples (click to enlarge)

Milky Way Widefield Shots

The Milky Way – Nikon D700, 24mm f/3.5, ISO 2000, single exposure

The Milky Way appears as a long cloud arcing across the sky when you view it with the naked eye, but that “cloud” is actually the combined light of billions of stars so tightly packed together and so far away that our eyes can’t distinguish them. With a telephoto lens you can distinguish a lot of them though and what you are presented with is a wall of stars. The darker regions in the Milky Way are vast clouds of interstellar dust blocking the light of stars behind them. The constellation Sagittarius is roughly the center point of the

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galaxy and when you look there you are peering to the middle of our galaxy though most of it is obscured since we are looking at it from the side.

Getting a good Milky Way shot is highly dependent on the light pollution levels. If you can find your location on a light pollution map (such as the one I linked to at the bottom of page 1) see what shade of color you are in. If it’s anything worse than green, forget it. Blue is better and Black is perfect.

The shot you see above was taken on the edge of a green zone, the problem was there was a small town directly south about 10-15km which is where this shot is pointing. Had the town been North instead I would have been able to capture more detail in the Milky Way.

As discussed in the star trails section, you can get away with around 30 seconds before trailing is a problem in a wide shot. In dark locations this is plenty of time to reveal the structure in the Milky Way, especially with a high ISO like 1600 or 3200. The best part to photograph is the Sagittarius region (the bottom part of the above picture) which has lots of detail and lots of small bright red nebula.

Suggested exposure for your first try: f/4, 30 sec, ISO 1600. Try one at ISO 3200 as well if your camera’s noise doesn’t get out of control at that setting. The Milky Way should be immediately apparent on your rear LCD when you preview the picture. Finally, don’t forget to take a series of dark frames for all the exposure settings you used.

If you want to take close ups of sections of the Milky Way or photography other deep sky objects like nebula and galaxies you will need to move onto the Advanced section of this guide. You will now need something to move your camera with the motion of the sky.

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The Milky Way – Nikon D700, 24mm f/5, ISO 3200, single 1 min exposure

Advanced Shots In this section we will discuss shots that require the use of a tracking mount. This will require a bit of financial investment but there are some budget-conscious options like the home-made barn door tracker.

Guide Navigation Introduction & The Basics | Beginner Shots | Advanced Shots | Photoshop Processing

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Without having a way to track the stars you are limited to star trails and ~30 second exposures. While you have a huge variety of pictures to take with that restriction (as seen on the previous page) you open up a whole new set of possibilities if you have an equatorial tracking mount as seen above. There are 5 main components to a setup like this. The Tripod, the tripod head for your tracking mount, the tracking mount itself, then a ball head and your camera.

Picking a Tripod You are going to want something more than you run-of-the-mill $20 tripod for this type of work. One suggestion would be the Manfrotto 055XPROB. This is a popular model and found for sale easily (Amazon, Adorama or eBay are options). Picking a tripod head for your mount

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The next piece of the chain is the tripod head that your tracking mount will attach to. There are 3 main types of tripod heads – pan/tilt (usually used for video), ball-head, and geared head. Any type will work as long as it can support the combined weight load of your tracking mount, camera and lens but the best type by far is the geared heads as they make fine tuning your polar alignment much simpler. With a ball head you will have to hold your entire apparatus as you align it – definitely possible but probably frustrating.

A popular choice is the Manfrotto 410 Junior Geared Head (Amazon, Adorama or eBay) which has a large weight capacity and very smooth and accurate fine tuning. It also has a built-in level which is helpful. Ball head for your camera The ball-head goes from your tracking mount to your camera. This is so you can keep your tracking polar aligned but freely move your camera in all directions to take different shots.

Any ball head will do as long as it can support the weight of your camera. I recommend something like the Manfrotto 496RC2 (Amazon, Adorama or eBay).

Tracking Mount Options

Home-made Barn Door Tracker With a couple pieces of wood and a few pieces of hardware you can make a tracking mount that you manually turn yourself (typically at 1RPM). Tracking

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won’t be very accurate but if you build it to exact specifications and polar align decently you can have widefield exposures of around 5 minutes without any trailing.

I built one following the instructions in this guide here before moving onto other methods. It is probably too shaky and inaccurate for telephoto shots but for wide or medium shots it will definitely get the job done. The downside is you will be manually turning it the whole time which means sometimes for hours at a time. Here is another guide for making one.

The Vixen Polarie portable tracker I really love the Vixen Polarie (Amazon, Adorama oreBay). It’s smaller than your camera body, runs off two AA batteries (2-3 hours of tracking on those) and is insanely easy to set up. It costs about $400 and that is priced very competitively compared to other alternatives. They also make a polar alignment scope for it for precision alignment that costs almost as much as the Polarie itself but I have had no problems getting good alignment using the little “polar sight” hole that is on the Polarie itself. I don’t think the scope is a necessary purchase unless you plan on doing a lot of 300mm+ long exposure shots. The Polarie also features lunar and solar tracking modes as well as a special 1/2 speed “starscape” mode where it tracks at half speed to better keep landscape elements from blurring but at the same time offsetting star trailing somewhat. It’s a cool compromise that lets you do nice 1 minute starscape

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shots instead of the regular 30 seconds while keeping both landscape and stars in decent focus.

I have now posted a more detailed review of the Polarie here.

The Astrotrac portable tracking mount The Astrotrac (Amazon or Adorama) was first to the market with an affordable and portable tracking solution for DSLR users. The Polarie wouldn’t exist without the success of the Astrotrac. Due to its design the Astrotrac is technically more accurate at tracking – accurate enough for people to use telescopes on it. It also holds a lot more weight than the Polarie but the downside is its less portable and slightly more expensive. It also requires 8 AA’s to operate instead of 2 AA’s and must be rewound after tracking for a while. It comes standard with a polar scope though at most places you can buy it and when you factor that in, its only slightly more expensive than a Polarie + polar scope combo. It features solar and lunar tracking modes like the Polarie but lacks the half speed starscape mode. One feature it does have is a tracking port for autoguiders to further improve tracking accuracy.

Piggy-back on a telescope If you already own a telescope on an equatorial mount with a motorized tracker you can simply piggy back your camera onto the telescope (there are adapters sold for this purpose) or even directly attach your camera to the

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telescope. That is called prime focus but I won’t be covering that here. I want to focus on what can be done with just your camera and regular lenses.

Polar Alignment

North America Nebula – Nikon D700, 105mm, f/2.8, 10x3min (18min total), ISO3200

In order to track the stars you must align your tracking mount to the celestial pole. Then the mount rotates at the same rate as the sky to keep the stars in place. For the barndoor tracker you would sight along the hinge and for the other mounts they have either a scope to use or in the case of the Polarie a small hole to look through. Alignment is different in the northern and southern hemispheres.

Northern Hemisphere Alignment The star Polaris is almost exactly at the northern celestial pole. If you know how to find “The Big Dipper” then you can find Polaris. Look North and use this diagram.

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Polaris is unmistakable once you first learn to find it.

Southern Hemisphere Alignment The star closest to the southern celestial pole is Sigma Octantis in the constellation Octans. It is a dim magnitude 5.5 compared to Polaris at magnitude 2. There are 2 main methods of finding it.

If you can see both Magellanic clouds, forming an equilateral triangle with the third point being the celestial pole gives you an easy way to find Sigma Octantis. You can also use the Southern Cross method as shown in the diagram to get you close to the pole.

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M51 The Whirlpool Galaxy – Nikon D300, 300mm, f/5.6, 6x2min

Stacking, stacking and more stacking Now that your camera is tracking the stars you can fully take advantage of exposure stacking. Stacking is when you take a bunch of images of the exact same thing and then stack them on top of eachother to improve the signal to noise ratio. This can drastically reduce the amount of noise in your final picture and all that extra signal will let you stretch the faint details of deep sky objects much better in post. In addition to regular frames (called light frames) there are other frames you should be taking to maximize the quality of your final image.

Light frames These are your regular pictures. Take as many as you can! Eventually you will hit diminishing returns for adding more exposures but more never hurts. A number I often use is 6. There’s nothing special about this number, I just find it to be a good compromise of quality and the amount of time it takes to capture it all.

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Dark frames I discussed these in previous parts of the guide but dark frames are identical to light frames except you put the lens cap on your camera when taking them. They are then subtracted from your light frames to remove all that unwanted junk. It is VERY important to take dark frames at the same temperature as your light frames as temperature has a big effect on noise and hot pixels. Like light frames you want lots of these to stack. I like to usually get as many dark frames as I do light frames. Flat frames Flat frames are used to remove vignetting, dust spots and other optical system anomalies. Flat frames should be shot at the same f-stop and focal length as your Light frames. It’s best to use Aperture priority with the lowest ISO setting of your camera (usually ISO 100 or 200). The goal is to get an evenly illuminated frame. If your camera has a histogram you want the peak to be right in the middle. One way I like to take flat frames is a clear twilight sky before you can see any stars. Aim the camera away from the sun so there’s no gradient and its evenly illuminated across the frame. You can also use a light box, or throw a few white sheets in front of the lens with a bright light source behind it. It’s good to take a few of these for stacking. Great, so you have all the frames. They will be useful later on in the processing section. One tip to remember is to shoot your darks and flats at the same orientation as your lights (portrait or landscape) – it just makes things easier when you are processing everything.

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The Orion Nebula – Nikon D300, 1000mm, stack of 10x1minute frames

What should I shoot? Here’s a few targets to get you started. You can use a program like Stellarium (free) to find these. There are also lots of books, iPhone/Android/tablet apps and other ways to help you find objects easily. • Hyades and Pleiades star clusters • Barnard’s Loop and the Orion Nebula • Large and Small Magellanic clouds (southern hemisphere only) • Andromeda Galaxy (best for 200mm+) • North America Nebula • The Whirl Pool Galaxy (300mm minimum) • Lagoon Nebula and Trifid Nebula • Omega Nebula and Eagle Nebula • Flaming Star Nebula • Horsehead Nebula

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4 nebula in one shot – from top to bottom: Eagle Nebula, Omega Nebula, Trifid Nebula, Lagoon

Nebula. Shot at only 70mm! So hopefully you have some shots to work with now. Let’s move onto the final part which is processing in Photoshop.

Photoshop Processing A lot of the techniques I describe here are most likely possible in other image editing programs but my only real experience is with Photoshop so hopefully it is easily translatable if you are using something else. I’m going to assume you have a working knowledge of Photoshop. This includes converting your raw files and getting them into Photoshop. If you are a complete beginner you will probably be lost but this isn’t a Photoshop beginner’s guide. I’ll also be focusing on a few Photoshop plugins that can greatly enhance your processing capabilities. There are some freeware tools we will be looking at too for stacking purposes. These will all be done in video format so I apologize if my monotone voice puts you to sleep.

Guide Navigation Introduction & The Basics | Beginner Shots | Advanced Shots | Photoshop Processing

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Stacking with DeepSkyStacker If you have more than just light frames you can use the freeware programDeepSkyStacker. I explain the basics in the below video. Note you will probably have to switch it to 720p or 1080p and go fullscreen to be able to read anything.

Basic Processing The easiest ways to immediately improve your image are to neutralize the sky background (basically white balancing) and correctly setting black and white

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levels. I also discuss how you can bring out more structure in things like the milky way or nebulosity. Note you will probably have to switch it to 720p or 1080p and go fullscreen to be able to read anything.

Noise Reduction Plugins The Photoshop noise reduction plugins discussed in this video are Nik Dfine 2.0 (also available at Adorama), PictureCode Noise Ninja, and Topaz DeNoise (my favorite one). Either plugin will serve you well and are much better than the default noise reduction that ships with many image editing programs. Note you will probably have to switch it to 720p or 1080p and go fullscreen to be able to read anything.

StarSpikes Pro plugin This little plugin is a way to add some character to your stars with Diffraction spikes and glow effects. It’s available from their website. Note you will probably have to switch it to 720p or 1080p and go fullscreen to be able to read anything.

Stacking Star Trails Here is a quick little video to show you how to stack multiple-exposure Star Trail images using the free Startrails application.

Final Words I hope you enjoyed this guide and it encouraged you to try your hand at Astrophotography. Please leave comments with your feedback and let me know if there’s anything big that I missed, anything I should change or if there’s more tutorials you want to see.

Links of Interest These are some links suggested by readers.

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Magic Lantern Firmware – Custom firmware for the Canon 5D MKII, T1i/T2i/T3i or 50d/60d and potentially more. This is a custom firmware that can add an in camera intervalometer, longer exposures, more shutter speeds, ISOs, and more. Canon Hack Development Kit – Allows you to take RAW exposures and have full manual control with many Canon “point and shoot” cameras. This may make some of them viable for some forms of Astrophotography. Another Barn Door Tracker – A third design for the home made barn door tracker. Backyard EOS – Camera control software for Canon DSLRs (hook up your DSLR to a laptop and take pictures from there) Astronomy for Beginners – Resource for both observing and astrophotography for beginners.