The hard edged photos is probably a result of the removal of the filter stack, which contains the anti-aliasing (AA) filter, responsible for moire control and image softening.
I've not come across any AA filter you can buy to mount on the lens but I know Kodak sells internal AA filters but the cheapest cost US$350 with the most expensive ones weighing in at US$1,500.
The cheapest alternative is to soften your images in PS.
Cheers,
Matt