I am creating pre-rendered sprites like in those classic pixel art games such as Commandos or Desperados. I use low render resolution 60x60 but the render results were blurry. And I found a nodes tutorial for render layer that makes the rendered image have sharp edges. This all works fine for bigger objects but when rendering the smaller ones as gun or knife it sometimes just crop all the pixels and the result is that the object is not visible in the end. I also use freestyle line set for my character though the gun is in a group that's not have apllied freestyle on it. And I am wondering if it is possible to keep the blurred pixels but give them color and not look transparent?
I would render at some multiple of the target pixel dimensions, and then take it into Photoshop. Edit the original and/or the downsampled result to get the features you want. For something that small, with just a few missing details, just paint it in using the pencil tool: turn anti-alised smudges into crisp (oversized) blocks; adjust the location of an edge so it downsamples nicely; etc.