ND Filter for 24-70 IS II

So this weekend I was up in VT and NH, and there were lots of waterfalls and moving water shots.

Immediate I realized why ND filters exist

Which would you recommend for this lens? They are big (82mm), so I know they aren't very cheap.

Is 10 stops too much? I was looking at B+W's.

I use a ten stop for water and most landscapes. You could also look at six stops. The b+w is great for the money. Although if you plan on using it on different sized lenses, look into a lee system our get some step down rings.

I use the Lee Big Stopper, along with other Lee Filters for my 82mm and have the rings for my smaller lenses.

It will save you a TON in filters down the road to have one set for all lenses, I highly recommend it!

I haven't shot a waterfall in a while. If it's overcast or dawn/dusk, I think a polarizer is all I needed at say f16. I also have a 3 stop if needed. I have a 10 stop but would never use that for waterfalls-too blurry for my tastes. I would rarely, if ever, want more than a few seconds on a waterfall. You can check your photos (assuming digital) and figure out what you would have needed to obtain a certain number (or fractions) of seconds on those days that you shot by examining your metadata.

I see you made it up to owls head while you were there. I use a Hoya ND400 (10 stop) and sometimes I wish it wasn't quite so dark as the water is too blurry or misty but you can always just move down the exposure time so I guess its not that big of a deal...Or maybe I should get a 5 stop one as well...

Since you have a 16-35 and a 24-70 you can just get a 77mm step down for the rest of your lenses. I like the idea of the Lee kit but it seems like bulky hardware to take with you and fiddle with. I am sure you get used to it though...

If you think you'll eventually want gradual ND filters, as well, then a square filter system like Lee makes a lot more sense for ND filters, too. Also, when using a 10 stop filter you will be attaching/detaching the filter more as you meter and focus, and I find the Lee holder easier for this purpose than using a round ND filter.

I still have a round CPL filter, though, as I shoot a lot handheld with this type of filter. For ND and grad ND's, though, I am always using a tripod.

Yes, if you have a split neutral density square filter, you can just use the darkened half of it.

Wow, people still use graduated filters? I thought everyone just blended exposures....(kidding)