4x4 (100mmx100mm) neutral density filters

[pyro701n]

Do they make neutral density filters (not grads) in a 4x4 format (for lee foundation holder) that are greater than 3 stops?
I know lee only makes 1, 2 and 3 stop ND's, but with the screw in type you can go all the way up to a B+W .9 which is like 9 or 10 stops
anyone know if they make a square ND that is 5 or more stops or light reduction?

[argyle]

The B+W 0.9 is a 3-stop ND filter. B+W does, however, make a threaded 10-stop filter, designated by 3.0. BTW...you can also stack ND filters to increase the strength.

[pyro701n]

ok maybe i misread the B+W designation, but either way, im looking for 4"x4" square ND filters, not threaded circle ones
also I am planning on stacking them using the lee holder. With the 1, 2, and 3 stop from lee ill technically be covered all the way up to 6 stops, but i would like to go higher than that and if possible do it without utilizing all 3 slots of the holder
if since lee doesnt make them i guess ill just have to go with the hitech ones from http://www.2filter.com/4x4camerafilters/4x4ndgraduals.html
or is there a better place to get them. I have a hard time believing that i can get a set of three lee 4x4 ND's (1, 2, and 3 stop) from B&H for ~$60 but have to pay over $60 each for anything above 3 stops (and from hitech none the less)

[argyle]

There's nothing wrong with Hitech filters, and they fit the Lee holder just fine. I use Hitech grads with my Lee holder. FWIW, the Hitech and Lee filters are made from the same grade and type of resin material. I seriously doubt that anyone can tell the difference between pictures taken with Hitech, Lee, or even S-R filters for that matter. The best that you can do with a Hitech 4x4 ND is 4-stop, IIRC.

2filter.com is a good source for filters. If you're not concerned about budget, Singh-Ray has a threaded variable ND filter (Vari ND) that will let you dial in anywhere from 2-8 stops of light reduction. They're a bit pricey, and only available in two sizes, 77mm and 82mm.

Also, depending on your focal length (as far as vignetting goes), you can always stack a CPL with your Lee holder...this will give you up to an additional 2-stops in light reduction to play with, in addition to your 4x4's.