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Boon
05-26-2011, 07:53 AM
Should I go for a 3 stop and 6 stop 77mm ND filter from B+W and Tiffen or a LCW Fader ND?
Are there significant difference between single coating and multi resistant coating (MRC) ND filter.

FS100 base ISO is 800, so on a bright sunny day, how many stops of ND do I need to shoot at f4?

morgan_moore
05-26-2011, 08:33 AM
a rough guide: 'sunny F16 '

thats with 100 ISO

so you need 4 stops to open to F4 and 3 stops to lower the ISO, thats 7 stops !

With my 5d which goes down to 100 I generally get by on a three stop

S

imag
05-26-2011, 10:07 AM
Don't forget, if you go for the standard NDs, you will probably want a circular polarizer as well.

speedracerlo
05-26-2011, 01:40 PM
don't forget the possibility of negative gain on the fs100, hopefully the production model will have it
also read that changing the shutter angle does not affect the video too much and it can be used to control exposure

I personally got myself a set of 4x4" 0.3/0.6/0.9 ND filters and a Linear Polarizer from Cavision for a good price, but without negative gain, this set definitely isnt enough

dustylense
05-26-2011, 07:38 PM
Polarizer on a 4.2.0 8 bit capture? Have fun. Variable ND's (a polarizer) is a solution, but you will get color cast and forget shooting anything with a sky.

imag
05-26-2011, 07:56 PM
Polarizer on a 4.2.0 8 bit capture? Have fun. Variable ND's (a polarizer) is a solution, but you will get color cast and forget shooting anything with a sky.

I am using a Schneider Circular True-Pol. I don't think color cast is an issue with that filter. Really appreciate the helpful tone though.

dustylense
05-26-2011, 08:22 PM
I am using a Schneider Circular True-Pol. I don't think color cast is an issue with that filter. Really appreciate the helpful tone though.
Thats not true ND though. again, won't do justice if a sky is involved, with an 8 bit signal to top that off. I would use a matte box with stacks of ND if you want the highest quality.

imag
05-26-2011, 08:38 PM
That's why I said "as well" on the pola. The midday filter stack we are planning on using is:

- Schneider Cir True-Pol if desirable (+1.3 stops)
- 1.2 Tiffen IR ND
- 0.3, 0.6, or 0.9 ND, depending on conditions
- Gradient ND, when appropriate (like when there is bright sky in frame)