Henning K writes:
If you google weather sealing Olympus Pentax you get to an 2013 article on www.thephoblografer.com stating that weather-sealed lenses by Pentax and Olympus do not need a filter in front to be weather sealed(with illustrations). But most Canons except some super-teles do need a filter like UV for instance.
I read another place that a Zeiss representative said the Batis lenses also need that.
I generally do not like to put filters in front, I always use a lens shade and have never had any problems.
I use my Pentax in all weather without problems, and would love to know if you have any comments or knowledge about this.
DIGLLOYD: I’ve checked with Zeiss. The Zeiss Batis lenses do NOT need a filter for their weather sealing. This is also true for Zeiss Milvus line which has multiple internal seals at several internal areas (and it’s why focusing has more resistance than the Otus line).
In general, I don’t see this as a major issue: any weather that would deliver water or snow onto the front of the lens would surely ruin any pictures made (water spots and similar). And if it’s blowing sand, a filter is mandatory anyway, to avoid damage to lens coatings (if indeed it is wise to integrate sand and grit into the lens and camera by photographing in such conditions).
On filters: I avoid filters. Recently, I determined that a high quality polarizer can add significant veiling flare under conditions I would not expect it (but not all conditions of course). To put a number to it, I have independent confirmation of a 0.7 stop increase in localized flare. As well, flare can veil the entire image. So my advice is in agreement with Henning: use filters only when absolutely necessary.