A Canon EOS 5D Mark III without Low-pass filter ? This is what James Miler, a genius insane DIY photographer has made, all by itself to measure the resolution difference brought by the absence of the anti aliasing filter which function is to blur the image in order to reduce moiré. In the path of the Fujifilm X-Pro1 which has suppressed the OLPW (Optical Low Pass Filter) to increase small details reproduction on the 16-megapixel XTRANS sensor. Nikon will also launch the filterless DSLR later this month, the D800E.
So this guy has teared the EOS 5D Mark III down, took the low pass filter away, replaced it by a layer of pur glass to prevent back focus issues as this would change the flange back of the lens-camera duo.
As you can see on the 100% shot bellow, the Canon EOS 5D Mark III without OLPF earns a lot of resolution. The difference is quite stunning both on stills and on videos. Today, moiré can be easily corrected with photography softwares like Lightroom or Capture One (used to deal with Medium format cameras that don’t have any low-pass filter). It looks like Canon is using too strong a filter on the EOS 5D Mark III that would benefit from a lighter one.