Anybody knows anything about
this (Rocolax) filter?
I am planning to use it as a drop-in filter for my Canon 400mm F2.8 lens, on ebay it is only AU$78 (+ waiting)
Looks like people did use it successfuly..
https://stargazerslounge.com/topic/1...d-modded-dslr/
Hoya also has filters that may be suitable:
http://www.hoyafilter.com/hoya/produ...lters/uvircut/
I couldn't find price info.
EDIT:
It seems Rocolax is slightly inferior, compared to Hoya.
But price/performance ratio is most likely superior, see here (from UV_IR_cut):
http://www.uvircut.com/48mm-optical-...ens-p-253.html