07-05-2010, 12:54 PM
Sylvian, I have the solemn duty to tell you the truth about ND definitions. ;-)
B+W uses ND numbers like this:
ND3 means 10 to the power of 3 (10x10x10): 1/1000 of the light is transmitted, the rest will be absorbed (and reflected). 1/1000 is (roughly) 10 stops down (2 to the power of 10 = 1024).
The others (including Marumi, Kenko, Doerr) are using quite another defininition:
ND3 means 1/3 of the light is transmitted.
Take care:
The Doerr ND8 will transmit 1/8 of the light = 3 stops down.
A B+W ND8 (not existing) would transmit 1/100,000,000 of the light ... about 26 stops down ... from f/1.0 to
f/8192 (+- a few thousands), i guess.
The question is: What are you looking for?
To stop down by 8, you will need two B+W filters ND1,8 + ND0,6 stacked. (= Type 106 + 102)
To reduce the light by factor 8 (3 stops) you need an B+W 103 or a Doerr ND8.
Confused? Don't worry, this mess is not covered in the english wikipedia nor in the german one.
Ciao, Walter
PS: I waited too long for the reply, I see you found the correct answer already.
I have the B+W Type 110. Take care, it is *not* neutral, you will get a red cast. I suggest to use a white balance card.
B+W uses ND numbers like this:
ND3 means 10 to the power of 3 (10x10x10): 1/1000 of the light is transmitted, the rest will be absorbed (and reflected). 1/1000 is (roughly) 10 stops down (2 to the power of 10 = 1024).
The others (including Marumi, Kenko, Doerr) are using quite another defininition:
ND3 means 1/3 of the light is transmitted.
Take care:
The Doerr ND8 will transmit 1/8 of the light = 3 stops down.
A B+W ND8 (not existing) would transmit 1/100,000,000 of the light ... about 26 stops down ... from f/1.0 to
f/8192 (+- a few thousands), i guess.
The question is: What are you looking for?
To stop down by 8, you will need two B+W filters ND1,8 + ND0,6 stacked. (= Type 106 + 102)
To reduce the light by factor 8 (3 stops) you need an B+W 103 or a Doerr ND8.
Confused? Don't worry, this mess is not covered in the english wikipedia nor in the german one.
Ciao, Walter
PS: I waited too long for the reply, I see you found the correct answer already.
I have the B+W Type 110. Take care, it is *not* neutral, you will get a red cast. I suggest to use a white balance card.