Barcelona, as seen from the Collserola.

The image was shot on Ilford Delta 100 using the Leica M7 and 21mm Super Elmar, and processed in ID-11 1+1. Both lens and film are extremely good, and the limitation on image quality in the digital images comes mainly from scanning rather than the original negative…

As an experiment, I scanned this image via a macro lens and an Olympus E-M1 mark II in both conventional and hi-resolution modes. The latter takes a series of eight images, shifting the sensor fractionally between each one. The result is combined in to a single image in-camera, yielding an 80 mega pixel RAW file – four times the normal resolution.

The high-resolution mode sounds great in principle, but in practice it is difficult to use fully. Even with the camera securely mounted on a tripod, the resolution exposes any defects in the lens, and any flaws in the alignment of camera and film plane are problematic to the extremely shallow depth of field. As a compromise, the image was shot at f5.6 – already well in to diffraction territory at 80MP, and then subsequently sharpened to compensate.

When everything is right the results are surprisingly good. The following three frames show crops comparing the high-resolution scan (right) and a conventional 20MP image (left) shown at the same effective magnification. Click on the crops in the gallery to view them at full size – the first image is from the central area (focus point), while the subsequent two images are taken from near the image edges:

The detail on the distant buildings taken near the centre of the film is clearly much better with the higher resolution, where you can make out the details of the balconies and windows. The advantage falls off towards the edge of the image, partly due to the film not being completely flat and partly because of some edge softness and increased chromatic aberration from the macro lens.

While I did not run a comparison here, the results are better than I would expect from either of the dedicated film scanners I have used (Epson V8x0 and PlusTek 7600i). Better still, the file sizes are also much more manageable – the 20MP and 80MP raw files weigh in at ~19Mbytes and ~66Mbytes respectively, whereas a corresponding 80MP TIFF file with ZIP compression takes an impractical 400Mbytes.

Using the Olympus is not a perfect solution for film scanning, but the speed and convenience combined with the resolving power and small file makes it the most practical approach that I have used.