Previsualisation
Previsualation

The other week I rose early to catch the sunrise over Blaven from Torrin on the Isle of Skye. Scheduled to rise just after 7am, according to The Photographer’s Ephemeris, I was hoping for some morning light on the east face. After some images by the shore of the loche I was ready for an early morning ascent of the south east ridge of Belig, climbing into the crystal clear spring air, with the mountains so sharp I felt as though I could reach out and touch them.

The ridge itself rises in one great sweep of steep grass and narrow rocky scrambling from sea level to the wonderful green summit plateau, with a raven for company and once up there I could see the potential of a photograph of the north face of Blaven.

Seeing the potential in a scene and how it will end up after processing is essentially what Ansel Adam’s describes in his technique of previsualisation. His images were interpretations of the raw scene he was capturing on film. He exposed in such a way that the camera recorded the various areas of the scene that he could then interpret in the darkroom. Burning here, dodging there. In effect, an early use of what digital photographers would recognise as HDR, or High Dynamic Range photography. His interpretations were subtle, intelligent and beautiful and they relied on previsualisation, exposing for the shadows and ‘placing’ important areas of detail in a suitable ‘zone’. This placing of exposure was dictated by what he could see in his mind’s eye.

With that in mind, the stunning view over to Blaven took on a new perspective and I wanted to bring out the naked rock and outline of the wild north face of the mountain. Back in the ‘darkroom’ I applied the zone system masks and got down to work. It was interesting to see that the rock was in zone 3, quite dark with some detail and I boosted the contrast to bring them more into the story of the face. The shaded snow and blue sky were both zone 7, which was instructive so I had to mask the sky when isolating the snow to bring out more of its texture. ‘Burning’ in the sky gave more colour saturation and helped give form to the ridge skyline as I’d ‘exposed to the right’ to get as much rock detail into the useful range of the sensor.

As I shoot in raw, the colour balance setting on the camera doesn’t really bother me much and I applied some colour correction before working on interpreting the zones. In bright sunlight the camera can sometimes impart a bluish tone for auto white balance but as it’s a raw image, the data is intact and the colour cast is easily rectified in post processing. Working in the shaded rocky areas, I identified a suitably dark portion of the image and used the individual RGB channels to neutralise the blue cast. I could have done this in Lightroom by changing the white balance setting but I prefer the intimate nature of working with pixel levels in Photoshop as it really gets me deeply involved in the digital ‘darkroom’. It’s even meditative at times.

I’ve got quite a few images from the climb that I want to work on over the coming months, all relying on previsualisation and the zone system.