How to Take Perfect Long Exposures
Mac users, we're pleased to announce Macphun's all-in-one photo editor Luminar is now available for purchase with special launch pricing. (Existing Macphun customers get a further discount.)
We rated Luminar as "Highly Recommended", and you can now visit the Luminar web site to try it for free.
There’s not much I miss about shooting film. It’s the pictures that matter in the end and the waste, the cost, the bracketing, the scanning, the wait to see the results; all of those film hassles seem increasingly like distant memories. I am a complete digital convert, I love the flexibility, control and quality I’m now achieving. I am not saying I’ll never shoot film again, I still have the big 6x17cm pano monster and it was taken out of mothballs briefly this summer, but it has to said it’s not seeing the light of day much.
I’ve just printed a shot from my recent Canadian trip made on the 1Ds mkIII up big, to over 1.1 metre wide, and looking at it now I’m wondering why anyone would bother with large format film. Crisp detail, sharp and noiseless with lovely evenness of tone and colour gradation; considering it’s enlarged from what we always thought of as a 35mm format it is truly remarkable. Nope, there’s no going back. But there is one major thing I miss about exposing large pieces of light sensitive silver halide emulsions; long exposures.
Using movement in landscapes, in fact in all photography, is an essential technique in a photographer’s repertoire. Trees blowing, grass swaying, water lapping, people bustling, clouds scudding and leaves rustling; we live in a world on the move and a bit of motion blur often transforms an image. How much motion to emphasise is of course completely down to the photographer, but often its difficult to slow exposures down enough to recognise discernible movement, particularly with modern DSLRs with default ISO settings of 100 or even 200. This is where large format film really scored. On my Fuji GX617 loaded with Fujichrome Velvia I started with an ISO of 50. Factor in a 1 stop centre weighted ND filter necessary with the 90mm lens to even out the coverage, then take into account an aperture often down at a miniscule f32 to get the depth of field necessary on such a large format.
Sunflowers blowing in the breeze at dawn with Montagne Sainte-Victoire beyond, nr Puyloubier, Bouches-du-Rhone, Provence, France. Canon EOS 1Ds mkIII, 24-70mm lens @ 27mm, ISO 50, 6 secs @ f22, 0.9 ND plus 0.6 ND grad filters.
Usually with landscapes I’m working at Happy Hour, that magical time before and after sunset or sunrise when the light goes through such wonderful transformations but is also losing much of its strength and already we’re talking about exposures in the tens of seconds. Then take into account reciprocity law failure, when the silver halide crystals start getting rebellious and stop behaving in a logical manner and hey presto it’s quite normal to be contemplating exposures of 30 seconds or longer. So using movement when shooting large format film is almost unavoidable. I couldn’t fight it so I ended up using it as a defining look to those images. With say a two or three stop ND to slow things down further the world really was my oyster in terms of bolting the camera down and letting the world sway in front of the lens. Now though, shooting digitally, I’ve been struggling to achieve that look, until now.
So, take an DSLR, say for example my Canon 5D mkII. I’m in a sunflower field in Provence (above) and the flowers are swaying nicely in the breeze as the sun comes up. I want to use this movement to get all arty and impressionistic, but the breeze is gentle and the sunflowers are only wafting languidly. On this camera I can dial in an extended ISO range which allows me to go down to 50. I can use a 3 stop neutral density filter to slow exposures down more, and I can dial in a minimum aperture of f22 on my 24-70mm f2.8 L lens. But I’d rather not. Diffraction at this aperture robs the lens of its optimum performance quite noticeably. Up big pictures shot at this aperture look just a little soft. It’s irritating and I do lie awake at night worrying about it. But to get a long exposure in this situation on this camera I have to. Even with all this the shutter is open for only 6 seconds; it’s not enough. I want more.
Lake Wakatipin, nr Queenstown and the peaks of Remarkables rearing above South Island, New Zealand. Fuji GX617, 90mm lens, Fujichrome Velvia, 0.9ND plus 0.9 ND grad filter, 2 mins @ f32
So, how much movement is necessary in a landscape? Well, sometimes the more the better. Clouds streaking through the sky can be a very tantalising effect, giving an other world look to a landscape, as of course can moving water. With this shot (above) taken on the shores of Lake in New Zealand an exposure of 2 minutes at dawn has streaked the clouds nicely. To record movement in skies the two factors that will determine how blurry your cumulonimbuses are will be the strength of the wind and the length of exposure. Generally speaking I find an exposure of at least 30 seconds on a breezy day is necessary to get a blur up top, but longer is often better; something like 3 minutes works a treat.