8 common mistakes you should avoid when shooting stars at night!

Every practitioner starts somewhere and they're bound to make mistakes. Here are 8 common mistakes made by astrophotographers that you can avoid!

1. Scout your area!

If you want to get a great composition, usually you'll have to look for it. Whether you're camping, going by car or just walking, you'll need to check around your chosen area before you decide on a shooting spot. Who knows, over that crest there may be a lovely clear lake, an idyllic landscape with a picturesque church, or a interesting piece of old, discarded machinery to use as a foreground object.

Not only is it good to check your immediate area to seek better compositions, it's better to get an idea of your area to understand its biology and geography. Knowing the shape of the land, nearest water source, tree cover, local fauna, nearest road, nearest population centre, ground materials, and even which way to run in an emergency, is all beneficial information in some situation or another.

My advice would be before even setting up where you have planned to setup, have a nice, relaxing walk around the area. Scope out the landscape, note where the local towns and villages are, see where the nearest road runs. It's usually pitch black when shooting the stars so aim (not always possible) to do this during twilight or earlier to get a better idea of where you are.

2. Don't be boring! Make an exciting composition!

One of the things I found when shooting stars for the first time was the importance of making a composition exciting. The principle of composition, or 'mise-en-scene' (literally translates to 'placing on stage') is a tool used throughout filmmaking, photography and visual art in general to make a 'scene' more visually interesting, or to aid the concept or narrative of the piece.

Star Photography is no exception to this. I think it's tempting when you're starting out shooting the stars - to just focus on the stars, rather than adding something in the foreground compositionally. This is understandable and I think it's partly routed in the fact that shooting at night - usually in a rural setting - is a different beast to other, more common types of photography. Long exposure times, using an intervalometer, ISO setting, finding a decent focus (especially on stars) and so forth begin to hem your ambition slightly and lead you to shooting a pretty boring scene of the sky, just trying to get your settings correct - and that's fine!

Due to the position of the sky in our world - that being upwards - it's a little more difficult to find a suitable foreground object to create a composition. It's important to note at this point that it's usually considered that everything that isn't the sky can be called the 'foreground' with decent amount of understanding. Depending on how wide your lens is, your elevation in contrast to your foreground object, and the specific position of any celestial subjects in the sky, it's quite hard to frame objects for your foreground whilst the sky appropriately in the frame. There are several ways to alleviate difficult framing problems:

• Using wider lenses (12mm, 14mm, 20mm etc)

• Taller objects (wind turbines, buildings)

• Standing well beneath your foreground object (close to an object's base, in valleys, next to cliffs)

• Shooting celestial objects when closest to the horizon

Popular compositional objects are church spires, wind turbines, old disused machinery, cars, trees, cliffs and rock formations, You! (the delay setting is good for something!)

3. PREP YOUR EQUIPMENT!

This one is fairly simple but very important! Have you formatted your cards? Batteries charged? Intervalometer packed? Mobile charged? Lens wipes? Lens heater?

There's nothing worse than arriving on your location, excited to begin shooting and to be served with the dawning realisation that what you had planned won't be happening because your intervalometer has ran out of juice and you've got no spare batteries; or you've forgot to flush footage off your card and now you're going to have to delete precious, unbacked-up data.

My advice: Avoid dissapointment by doing it the night before, give yourself plenty of time for surprises to happen in your home, not out in the field.

4. Check settings, test and be sure.

Arguably the most important point on this list, exposure and settings. Adjusting your settings correctly will give you less work to do in post so you want to get this right there and then. Make sure your camera is on manual mode - providing you're shooting with a intervalometer - and allow yourself time to reach a suitable exposure for the composition your shooting.

Astrophotographers shooting for non-video purposes who do not have trackers generally want to avoid longer exposures due to the micro-trailing that occur in their images - even when adhering to the '500 rule' - meaning the objective is to get as short an exposure time as possible, without needing to bump up your ISO too much, whilst maintaining a balanced, correctly exposed image. With this in mind, it's a good idea to trial-and-error various settings: see how your camera handles higher ISO shots, see how low you can get your exposure time, see how focus is at different apertures.

The considerations for shooting timelapse video differs slightly but doesn't stray too far from these basic shooting considerations. Timelapses rely more on interval times and exposure lengths than when compared to shooting exposures that are intended to be produced as images. Timelapses represent a scene over a long period of time, where as images, bar star trails, supposedly, but rarely, represent a scene in a single exposure length - this is due to astrophotographers blending, stacking and mixing exposures to create a single image; these are called composite images.

5. Lens fog

Hugely irritating, hugely disheartening, and very difficult to alleviate without the correct equipment. For single shot astrophotography, it can be combated without too much hassle by regular lens wiping but timelapsing over an extended period of time throws up some difficulties. Returning to your camera, eager to see your timelapse, only to see each image becoming progressively foggier until being rendered as a large, soft blur, is quite the shitter.

Lens 'fogging' is effectively condensation gathering on the glass of your lens. It occurs when the lens glass is cooler than the air surrounding it, making the warmer, humid air to collect on the glass and form moisture.

Fogging is further induced by humidity in the air and is particularly prevalent on cool, winter nights; cool, windy nights further compound the effect by dropping the temperature of the glass. Lenses with protruding glass are particularly susceptible to fogging due to the extremity of the glass, not dissimilar to how the ends of your fingers and nose become colder in lower temperatures.

There are several ways to protect your lens against fogging, some depending on your equipment and location.

A simple modification to your lens, creating a 'hood' around the glass to protect the glass from the crossing wind, though this won't always provide a solution.

A more reliable way would be to use a dedicated lens heater, usually powered by a dedicated supply or power bank fed by USB cable. More makeshift would be to use press-activated hand warmers stuffed into a lens sock.

6. Is your tripod stable?

When shooting a timelapse, it is imperative that your tripod stays completely still throughout - especially when shooting at night. Shooting at night almost certainly means very long exposures of us to 30 seconds, or more if shooting with a star tracker or single exposure star trail.

Wind, loose ground or a knock from the operator will cause the camera to shoot a slightly different frame from a slightly different perspective than before. Objects will appear blurry due to camera movement whilst the shutter is open. All the stars will form uniform dull 'streaks' across your image, becoming more pronounced with more movement.

The obvious solution to this issue is a bigger, heavier tripod, though these are expensive and not always ideal to lug out into the wilderness, since areas of low light pollution are almost always away from built-up urban areas and in rural areas. A cost free solution championed by many is to hang a satchel of rocks - or similar heavy objects that can be found around your shooting location - off the central point of your tripod; some tripods even come equipped with a hook or mounting point for this very function. Similarly, laying rocks or heavy objects on your tripod legs can be effective, but do this with caution as rocks can displace themselves once stacked and cause the very problem you're trying to solve. Finally, probably the best rule to adhere to is to mount your tripod legs on as flat a surface as you can find, additionally, a solid surface that will not crumble is also essential.

7. You're in for the long haul.

Depending on how long you want your timelapse to be, you're going to be out in the field for at least 2 hours, not including setup and pack-down time: a 12 second timelapse with a 25 second interval would be bang on 2 hours shooting time. A longer interval time, longer timelapse or higher-fps timelapse will require more time; besides this is all under the assumption you're doing just 1 timelapse. It's not uncommon for night timelapsers to work from dusk until dawn, demanding a temporary inversion of your sleeping pattern.

Once the timelapse is set, you don't have much to do. Bring a book, sleep, have some thinking time, whatever, it's up to you. One thing I would definitely recommend is take climate-appropriate clothing. This summer whilst shooting in a field in Germany, I managed to catch 2 hours sleep as I slept in my sleeping bag next to a hay bale - in winter this would be a different story.

8. Allow enough setup time.

A mistake nobody likes making. Rushing a timelapse setup inevitably causes mistakes. Trying to beat incoming weather, avoiding brightening skies, arriving on location late, or not allowing time to test exposure properly - leading to more work to do in post - are all reasons why you might rush through your setup.

It's infinitely better to have more time than less. Giving yourself more time for setup allows you do really flesh out that composition and perfect your framing, get all the dark frames you need, plan you stacks and panoramas is a very good idea, especially when your shoot schedules are becoming more convoluted with dark frames, light frames, flat frames, stacking, foreground shots and panoramas; combine this with framing, anti-fogging method, setting up intervalometer, finding focus & exposure, you can see why time can run through your fingers.

Simple advice, just get their earlier. If you're worrying about not having enough time, this probably means you need to get to your location and begin preparation.