https://www.dpreview.com/news/0569067557/ricoh-gr-iii-gr-iix-hdr-highlight-diffusion-filter
Interesting development which I wouldn't have expected. An additional couple of GR cameras with the ND filter swapped out for a filter which creates something similar to a black mist/promist look in highlights.
Not something I would be interested in, but I know that diffused highlights look is pretty trendy. Could this have been done as a firmware update, however?
There is mention of AF focus zones being added to firmware, which could potentially speed up AF by limiting the focus range to a set area, if I'm understanding it correctly.
*Actually, the zone AF just means that you can move the 9-point center AF grid around to position it where you want in the frame.