Surely all variable ND filters include a CPL the first part has to be a linear polariser, and while it works to have a linear as the second this limits there use as many cameras use polarisers for the AF & exposure sub systems, and these get messed up without the quarter wave plate.
I've seen filters in flavours of ND with a fixed value, variable ND value and now ND's combined with a polariser however I've only ever used fixed ND's.
I see, I never shoot video, but would rarely stick to f/2.8 either (my long lenses don't even reach 2.8)
A normal polariser will block roughly 50% of the light, unless two are used together. Normal ND filters usually block more there are multiple ways of describing them but the simplest is the number of stops it changes the exposure by, 2 stop, doubles the exposure, 4 stop quadruples it... I have ND filters from 2 stops to ~18 stops, the darkest of these blocking UV & IR as well so is safe for viewing/photographing the sun.
If you want to shoot at say f/5.6 and 1/50th second on a sunny day you will need around 3 stops of ND if you want to shoot wide open at f/2.8 you will need around 6 stops.
If you want to shoot at f/2.8 I would start with and ND64 and go from there. The best ones are B&W/Polarpro at about £150 all the way down to K+F which are about £50. Although I always buy filters used.any reccomendation on make? or actual filter please.. been googling and youtubing.. colour casts and vignetting... only being use don 70-200 ... so people actually used them on here i would rather take note of
i do want f2.8 mostly
Yes and no... AFAIK, all VND's use a CPL nearest the camera for the reason you noted. But because the orientation of the CPL is not variable relative to the orientation of the light VND's do not do a good job of cancelling polarized light/reflections.
I can't specifically recommend a particular VND as the one I use is no longer in production (it's also not particularly great). But I have been very happy with the NiSi filters I have purchased. I find there can be a lot more variability with the other brands depending on which "line" you go with... and unfortunately price isn't always the best indicator. That said, the NiSi filters I have bought have not been cheap.any reccomendation on make? or actual filter please.. been googling and youtubing.. colour casts and vignetting... only being use don 70-200 ... so people actually used them on here i would rather take note of
i do want f2.8 mostly
I haven't used any K+F filters but they come out OK in reviews, it's had to see how you can go far wrong for £20. You will probably get some colour cast but providing you adjust for it that shouldn't be an issue.This one?
K&F CONCEPT ND64 Lens Filter 49/52/55/58/62/67/72/77/82mm Nano-X Ultra-clear UK | eBay UK
It is very suitable for shooting landscapes. ãDouble-sided multi-layer enhanced coatingã The filter material is top-quality optical glass, and the double-sided multi-layer enhanced coating is used to effectively reduce the surface reflection of the filter.www.ebay.co.uk
If you're pretty sure 5 stops will be enough. If not, the swift version has an additional 4 stop add on filter to make it a 5-9 stop VND... of course it almost doubles the cost as well.
Yes but that's not obvious when viewing from What's Newwe are in "talk video"
To honest all stronger Nd filters will give correctable colour cast, and sometimes strong one. Premium brands are certainly not immune to this
Color casts are never fully correctable. Particularly a color cast caused by a filter; and that is because a filter affects the different photosites unequally, and the photosites are also weighted unequally when determining the demosaiced color. Even just an ETTR shift and recovery will cause color shifts that cannot be fully corrected in post... you can correct some colors, but it will not be correct for all colors.
I would say that is a very good analogy... i.e. you can get a zoom that compares well to a prime, but it costs exponentially more.
