Sitges – and Lens Cast Corrections in Capture One
A short set of images taken on a walk in Sitges. Shot on digital using a 35mm lens and polarising filter.
Incidentally, the vignetting on some of these images is completely natural, although perhaps exaggerated slightly by the skies and polariser.
The lens is a Zeiss ZM 1,4/35 (35mm f1.4), which is nice and small and incredibly sharp, but which pays for that to some extent with dark corners shot wide open – a common problem with Leica lenses shot on digital rather than film.
Here is a gratuitous shot of a uniform white panel (my laptop screen shot out-of-focus from a few cm distance) taken with the lens wide open, which shows how drastic the effect is:
Unfortunately, Capture One does not have a model for the Zeiss lens, and it is not possible to correct the vignetting automatically using the lens correction tool. However, it is possible to use the above image to create a Lens Cast Correction profile (LCC) and then apply that to specific images. And it turns out that this is really easy to do.
First, select the uniform image (above) in Capture One and find the “LCC” tool panel, where you can click the “Create LCC” button to turn the reference photograph in to a special image that can then be applied to other photographs. The LCC corrects for light fall-off, colour casts and dust – although in this case it is mainly the fall-off that is the problem.
Having created the LCC, go to the image browser and select both the LCC reference and the images that you want to apply it to, and then select “Apply LCC” from the Adjustments menu. You can adjust the degree of vignetting correction via the “Uniform Light” slider in the LCC panel for each image:
The following shows the result both with and without the correction applied:
Aside from providing corrections for unruly Leica lenses, this is also a fantastic tool for working with shift lenses. With a shift lens, vignetting and colour casts are usually asymmetric and dependent on the degree of shift that was used. Capture One’s LCC mechanism makes it comparatively straightforward to create and apply corrections for this.