Film Test – Stuart Brown Photographic has tested two film emulsions at Shrewsbury Abbey. A test shot of the Abbey Chancel showing the organ during a practice session and the screen behind the altar has been taken and published on my Google+ page.
The black and white Ilford HP5+ film showed excellent handling of the various light sources and the dynamic range of the image despite the exposure having to be increased by two stops due to reciprocity failure in the film at low shutter speeds. The final exposure was 1 minute at f22 (ISO 400), a 5 second exposure was measured in an area of average exposure for the scene which was then corrected to 15 seconds to compensate for the 1.5 stops of the centre filter used to overcome the darkening effect at the top of the image due to vertical shift of the wide angle lens then to 60 seconds in line with film manufacturers guidance. A small area at the top right of the image where bright sunlight streamed in through a window managed to hold all the detail of the masonry, overall a very impressive result considering the lighting conditions.
Kodak Portra 160 colour negative came up next, here a base exposure of 12 seconds at f22 became 30 seconds and was then doubled to 60 seconds to allow for reciprocity failure. Kodak are less helpful in providing guidance on reciprocity than Ilford. Kodak’s technical documentation simply tells you that if correct exposure is critical where long exposure times are required then test it yourself, i.e. trial and error. The result with the Kodak film was overall satisfactory, however the bright area on the right hand edge of the image did lose a little detail that could not be brought back by dodging but the shadow areas did appear a little less dark than the black and white film.
The shots were taken mid afternoon when the sun was shining on the south side of the abbey, this timing was deliberate as I wanted to see how far I could push the film. By analysing the sun’s movements shooting at around 17:30 hrs would have solved this, however the abbey closes at 16:00 hrs.