Birds VF-DCPL1 circular polarizer

[Malsam]

Does any long prime users like a 600 GM or 400 gm uses a VF-DCPL1 circular polarizer during wildlife or birding? I know landscape is a definite yes, anyone find it useful? Affect brightness etc?

 

[mark.s]

Does any long prime users like a 600 GM or 400 gm uses a VF-DCPL1 circular polarizer during wildlife or birding? I know landscape is a definite yes, anyone find it useful? Affect brightness etc?

Did you ever try one of these filters? I do a lot of bird photography on fast running rivers and coastal areas where the 600f4 picks up loads of background light circles and I'm seriously considering buying the drop-in filter. At £360, it's another expensive addition but if it saves me ages in edit, probably worth it. Any feedback would be welcome, thanks.