Photographing lichens in winter; as the year moves towards the shortest day and light levels at their lowest lichens are often looking their best. They are not plants but are a symbiotic relationship between fungi and algae which can take many forms. From minute crustose types growing on rocks to much larger foliose and shrubby lichens festooning trees and rocks. The semi-natural woodlands of the Western Highlands, sometimes referred to as the ‘Celtic Rainforest’, have a particularly rich and varied lichen flora. They often grow along with epiphytic mosses and liverworts on trees in such profusion that little bark remains exposed. The lichens best represented in the western woods are the lobarion lichens. A community associated with the more alkaline barked tree species such as ash, elm and hazel. Acid barked species like oak and alder support another less flamboyant community, the parmelion lichens. Whilst it is true that many lichens can appear dull brown or grey in colour some like the foliose Lobarias and the shield like Degelias and Pannarias with their ‘jam tart’ like fruiting bodies provide a splash of colour on a dull winter’s day.
Photographing lichens is relatively straight forward. Close up using a macro lens in low winter light a tripod becomes an essential. Getting sharp images with enough depth of focus has become something of a problem with modern megapixel stacked cameras. An aperture of f11 is past the point at which optical diffraction starts to degrade and soften the image with some cameras. Ways round this are to shoot at wider apertures with shorter focal length lens and maybe to crop the final image. My preferred method is to use a 180mm macro lens at between f5.6 and f8 and create a focus stack of 20 or more images. In the right software the stack can be blended together to produce a front to back sharp subject with nice, defocused background. With my old DSLRs creating a stack used to be a bit of trial and error. Inching the camera and lens on a focus rail to get a series of images to make a stack. These days it’s just a case of setting the right parameters in the cameras stacking programme, pressing the shutter and standing back.
