Night Photography Beginners Guide, Part 2: Choosing a Lens

Two words: “Go Wide!” No, make that three words: “Go Ultra Wide!”

For outdoor night photography, a wide angle lens is my first choice. A wide lens gets more stuff into the picture. You can get up close to your subject and still capture an expansive background, whether it be the sky, trees, hills, whatever.

As in this shot:

Like most of my night photos as of December 2010, I used a Canon 10-22mm lens set to 10mm. You’ll notice both the  green shed and hills in the far distance are clearly defined; yet another advantage of using a wide lens in the dark. With a regular lens, to achieve focus on objects both near and far, you’d have to close down the aperture (f stop). This reduces the amount of light hitting your camera’s sensor. OK, the logical solution is to use a longer shutter speed to compensate. In daylight conditions that scenario is no big deal because the shutter speeds you’re dealing with are so short i.e. increasing a shutter speed of say 1/60th by 4 stops gets you to 1/4 second. But at night,  4 extra stops on top of 2 minutes equals 32 minutes! Unless you have a high end, full frame camera, it’s generally advisable to keep shutter speeds under 5 minutes to avoid the sensor overheating. Overheated sensors produce noise that will ruin your shot.

Here’s where the wide angle lens really benefits us night shooters… the wider the lens the greater the depth of field for a given f stop. For instance, my 10-22mm lens allows me to use f5.6 and still achieves great focus over large distances. You can pretty much get everything nice and sharp from 1 metre to infinity. This allows a nice balance between using a wide aperture to keep shutter speed within a reasonable range and still have everything in the image well defined.

If you were to try the same f5.6 setting on a longer lens e.g. 50mm or greater, you won’t have anything like the same depth of field. maybe that’s the effect you’re looking for, but for this particular outdoor night photographer, the wider lens  delivers the best performance for the type of images I’m trying to create.

Are there any downsides to using a wide lens? Unfortunately, yes! If you have your camera angled upward, e.g. shooting a tall building at close quarters, you’ll find vertical lines lean inward at crazy angles. Technical geek-speak, proper photography term for this is ‘converging verticals’. The more you tilt the camera from the horizontal, the worse the problem. It can add drama to a shot if you like the effect but in most instances you’d probably prefer to avoid it. The most extreme example I’ve got to hand is this photo of a nissen hut with nearby telegraph pole.

I set the camera as low as I could reasonably go on the tripod (approx 30cm/1 ft off the ground), with a severe angle upward to cram in the top of the telegraph pole. Despite appearances to the contrary, the pole is actually vertical (in real life) but it’s easy enough to see the ‘converging verticals’ effect on both the telegraph pole and the weather vane.

How do you avoid this problem when using a wide angle lens? Easiest solution is to stand further back and can reduce the camera angle. You can also tweak the image in post production by applying a distortion correction – a topic I’ll cover in more detail when discussing software and plug-ins. But aside from issue of ‘converging verticals’, you can’t beat a wide angle lens for capturing the drama of an outdoor scene at night

Before I sign off, a quick mention of recommended wide angle lenses. In my case, I was lucky enough to find a used  Canon 10-22mm lens (eBay). I paid £380 – exactly twice what I paid for my Canon 20D camera! Used lenses hold their value extremely well and in some instances I’ve seen a used lens go for more than a brand new one, so don’t get carried away in a bidding war. Check best price on a new one – you might prefer the safety of buying new and benefiting from the manufacturer warranty in the unlikely event you have a problem.

There are a couple of aftermarket alternatives to the Canon 20D. I’ve not used them personally but they come highly recommended: Tokina make a 12-24mm wide angle lens to suit both Canon and Nikon crop sensor cameras. Obviously not quite as wide as the Canon but I know people who get excellent results with it. Sigma produce a 10-20mm lens. Again, I have no personal experience but I’ve read reviews from many satisfied owners. If you find a deal on any of the above, I’m sure you’ll be happy with the results.