|More stars than you can see .... but the camera can|
Photographing starry skies and campsites at night Is something I’ve done for decades but only in the last few years have I started to take it seriously and think about the best way to get good results. Experimenting with different settings on the camera, different lenses and different ways to use headlamps to illuminate camps has been an interesting exercise.
One of the first things I learnt was that all my lenses distorted stars slightly so they appeared to have short, comet-like tails or else were elongated into ellipses (an effect known as coma). Not having a fast lens was part of the problem as it meant I had to use long shutter speeds that recorded the slight movement of the stars during exposure. It also meant I needed to use higher ISO speeds, which resulted in more noise in the images. Most lenses aren’t that sharp at their biggest apertures either.
Research on the Internet came up with one fairly unique fast wide angle lens designed for mirrorless cameras like my Sony NEX 6 and 7 – the Samyang 12mm f2 NCS CS – that was recommended for star images and said to produce good quality wide open at f2. The price was low and the lens lightweight (278 grams) so I bought one. And after my initial use I can say I’m pleased with it and feel it’s certainly worth the money.
|The Samyang 12mm f2 lens fitted to the Sony NEX 7.|
The lens is fully manual with aperture and focus rings. There’s no electronic connection. All you can set with the camera body is the ISO and the shutter speed. Having used lenses like this for many years with film cameras the lens didn’t feel unfamiliar though it probably would to anyone only used to fully automatic digital lenses. Manual focusing isn’t a problem for two reasons. Firstly 12mm (equivalent to 18mm on a full frame/35mm camera) is so wide that depth of field is enormous even at large apertures. Secondly the NEX cameras have ‘focus peaking’ that gives sparkly coloured edges to the areas in focus. For night photography I’ve used the lens set to infinity anyway and wide open at f2.
Compared with night shots from my other lenses the Samyang 12mm definitely produces more pinpoint stars with less coma. It also lets in enough light at f2 that I can use lower ISO and shutter speeds. The night image accompanying this piece was taken at ISO 400 with 8 seconds exposure.
|Crop from the image below|
A fast lens like this plus a digital sensor can capture far more of the stars than you can actually see. The two versions of the image here show this. The darker one approximates what I could actually see, the second one what appears when the exposure is increased in Lightroom.
|Closer to what I could see ... though there's still probably too many stars|
The Samyang lens was used for the night photos in my post on camping on Ben Macdui – link here. That’s the only backpacking trip I’ve taken the lens on so far. I doubt I’ll take it on trips of more than one or two nights because of the extra weight. My Sony E 10-18mm f4 zoom lens is more versatile though not quite so good for star images. However I will carry the Samyang on shorter trips when the forecast is for clear skies.