Weekend Project: Capture star and star trail photos

One of the reasons why I headed off to an island with no electricity and the minimal of artificial lighting was in order to capture some photographs of stars and star trails. While the weather wasn’t entirely cooperative, I was able to get a few shots that I was pretty happy with.

The kit you'll need

See also: Yes, smartphones have killed the DSLR

Want to capture similar – or maybe even better – photos? Here's what you need.

• A clear, relatively dark, night sky
• A DSLR (I'm a Canon guy for my sins, but if you've got a Nikon, Sony, etc, it doesn't matter)
• A lens plus hood (whatever lens you've got will work)
• A sturdy tripod
• A cable release for the camera (if you don't have one, there are alternatives you can use)
• A flashlight (low-power if at all possible, so you don't destroy your night vision – not to mention the night vision of those around you!)
• An image processing tool (Lightroom, Photoshop, Photoshop Elements are the only applications I have any real experience with)

One question I get asked a lot is "Do you really need a DSLR for night photography or will compact/bridge/mirrorless work instead?" In my experience, the camera does have to be a DSLR as other cameras just don't have the light collecting power. On the upside, almost any DSLR sold in the past few years will do fine, whether it has a full-frame or cropped sensor.

As far as lenses go, try whatever you have. Wide is best for capturing more of the sky, and if you have a good lens with a low F-stop, go with that. But if all you have is the kit lens that came with your DSLR, that should work fine too. There's no doubt that a better lens will result in a better, sharper image, but you can still get impressive, even breathtaking results with cheap gear.

If the lens came with a hood, fit it, as it will not only prevent lens flare from stray light, but also offer it a bit of protection in the even that you bang it against something in the dark.

OK, so you have the camera attached to the tripod and pointed at the sky (if the moon is out, point away from it as it will just blow out your image) you're ready to roll. Here's how:

Connect the cable release to the camera

Stars are small, dim points of light, and the last thing you want to happen when you take a shot is to be pressing the button manually. This is a recipe for camera shake. This is why I use a cable release (I use a cheap, no-name brand one I picked up from Amazon).

If you don't have one then you can use the camera's built-in self-timer feature (consult your manual, it will be buried somewhere in the maze of menus). This gives the camera time to settle down before taking the shot.

Focus

Getting the focus right in the dark can be a real challenge, and even for the experienced it can be a bit hit and miss, especially if you have something in the foreground of the shot.

Here are a few methods you can use:

• Focus on something far off during the day, then switch the lens to manual focus and lock it off with some gaffer tape
• Use a bright light at night and focus on something far in the distance, then switching the lens to manual focus
• Manually focus on a star or something else you can see off in the distance

Whatever you do, remember to:

• Put the lens onto manual focus so the camera doesn't hunt for focus in the dark
• Take a test image and check it for sharpness using the live view feature

Camera settings

OK, you now need to input the settings into the camera. I suggest you start with the following (you will most likely tweak them):

• Set the camera to manual (M on the dial)
• Set the shutter speed to 30 seconds
• Set the aperture of the lens as low as you can go (around F2.8 to F4)
• Set the ISO to 400
• Shoot in RAW (if you can process these sorts of files)

Shoot!

Take a shot and admire the results using the camera's live view. Zoom in on a star and see if you've captured a bright point of light. You may be happy with the result, or you may need to tweak:

• Star is a streak rather than a point – Test faster shutter speeds between 10 – 25 seconds.
• Dim stars – Bump the ISO up (but keep an eye out for noisy images)
• Sky too bright/noisy – drop the ISO

Try more test shots. If you shoot in RAW you will be able to clean up/process these images significantly using tools such as Lightroom/Photoshop/Photoshop Elements – but this is beyond the scope of this post.

From star shots to star trails

See also: Great debate: Have smartphone cameras killed the DSLR? No!

Once you're perfected capturing a single shot of the sky, you are ready to progress onto taking star trail images. To do this you essentially take multiple star photos and 'stack' them in a tool like Photoshop. This process is essentially like taking a single shot, except that you need enough space on the storage card to store dozens, maybe hundreds, of images.

You also need a method of keeping the camera firing without you pressing the button. I recommend using a cable release, but alternatively you can take a piece of eraser and a rubber band and use this to keep the shutter depressed. It's old-school and a bit fiddly, but it works.

Then you start shooting. I suggest if this is your first attempt, you shoot for some 15 to 20 minutes.

Post processing

Once you've taken the shots, you then have some processing to do. There are a myriad ways you can do this – if you are starting out I recommend a free tool called Startrails – the best tool for Photoshop users is Advanced Stacker+. This tool, created by Steven Christenson, "Astronomy Photographer of the Year 2010/12" and founder of StarCircleAcademy.

Advance Stacker+ is an easy to install and easy to use advanced Photoshop action that not only allows you to create a myriad of different star trails, but also helps you enhance your images. I'm not going to attempt to cover what Advance Stacker+ does here because there's just too much to cover, and Christenson has written detailed instructions covering all of its features.

For $27.50, this is a must-have tool for anyone who is serious about star photography. Christenson's site is also a treasure trove information for the budding, and the not so budding, night-time photographer.

Final thoughts on kit

For those interested in kit, here's what I used for the shots:

• Canon 5D MKII
• Sigma 15mm F2.8 EX DG fisheye lens
• Manfrotto 055CXPRO4 carbon fiber tripod with ball head
• SanDisk Extreme CompactFlash cards

I also have tools for taking the noise out of images. I use both Topaz DeNoise and Nik Define 2. Both of these are great tools and are far superior to the noise reduction tools built into Photoshop and Lightroom.

So, got a DSLR and tripod? Why not give it a go this weekend! Feel free to share with me any photos you've taken!