Tuesday, 19 May 2015


Whilst shooting some surf footage a couple of weeks ago, a Canon stills camera fitted with a 300mm lens, which was being used to capture some from shore action was dropped - small particles of sand got onto and into the lens.

During the edit session, a couple of the shots proved to be worth keeping, and whilst we were running a 2:35:1 crop and lost much of the edge dirt, de -focussed blobs still existed.

To the rescue, PFClean.

I exported the 1920x1080 progressive clips as DPX files which is the PFClean source file requirement, it accepts not, any .mov or other stream of vision. I used a default DPX output from PPro CC14 - which does this job very quickly, and imported the folder to my newly set up project in PFClean. In the filter section I selected "Clean lens dirt" This filter requires you to select marquee areas where the dirt exists, you can do them one at a time, or multiples, preview allows you to see the result immediately, and very impressive it is too - the larger the area selected, the longer the processing time is, but on my 16 thread 4.5gHz system, it was almost always pretty well instant.

It is possible to set the dirt detection to Dark, Light or both, multiple passes of the same area usually result is image aberrations, some testing and fiddling is required for best results. I was not able to find a way of saving the "map" of a particular dirty lens for use on other clips - maybe there is a way, but not obvious.
As with all post remedial work, not everything cleaned perfectly, but it rendered shots use-able where previously, there was doubt about including them.

shot before treatment
and after
top left corner at 200% before cleaning

and after cleaning.

whilst there are still some residual errors which I did not bother to worry about as they were cropped out in the edit, the final movie clips were a huge improvement.

Dylan's video is here:
Making my own surfboard

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