Mountain Range, Laguna Colorada, Bolivia
Phase One A-Series, IQ4 150MP back, 180mm Alpagon, f11 @ 1/250 exposure, ISO 50, exposure averaging.

I'm watching Ignacio and the six photographers who accompanied us to Bolivia last month uploading some amazing photographs, so I thought I'd better step up to the mark.

This image is taken using the new exposure averaging feature on the Phase One IQ4 digital backs. It can work like a neutral density filter, except it takes tens or hundreds of exposures, one after the other, and 'averages' the results into a single raw file. This means that white clouds crossing a blue sky over a period of 15 or 30 seconds might be exposed 500 times and the resulting 'average' creates a blur, just like an ND filter. The parts of the subject that don't move remain tack sharp. Olympus has a similar system for some of its cameras.

However, keeping the camera completely still for the 15 seconds (or five minutes etc) was challenging up on the Bolivian Altiplano. On some days, it was a challenge enough just to stand up, let alone put a camera on a tripod. This shot was taken in the early morning before the winds came up, whereas other shots I took later in the day using the same technique are a little blurred: you can see the camera shake in the file and nothing is as sharp as it should be. Of course, this doesn't matter for the blurred water or clouds, but it's certainly an issue for the mountains!

This is why I take a standard back-up shot as well. Whether I'm using an ND filter or the new exposure averaging feature, my first shot is at a faster shutter speed like 1/250 second, so I know I have an image that is tack sharp. If the long exposure is then slightly blurred due to camera shake, I can merge the two images together in Photoshop using layers and end up with the best of both worlds - a tack sharp mountain with nicely blurred clouds.

Now, who was I talking to the other day who hates the fairy-floss effect of blurred clouds? Well, it doesn't matter anyway - I like it!

Oh, and if you're interested in a little video I put together on our trip, here's the Youtube link: https://youtu.be/1F7rsOlbwkU - or Google search Youtube, Eastway, Bolivia. I've had a few comments from Bolivian viewers unimpressed by my choice of music, so I'm on the lookout for some pan pipes instead!