ND Filters

[SoulfulRecover]

What do I need to know about them? Im looking to use my Alien Bees out outside for portrait work and would like to use a "shallow" DoF around the f4 area but need to keep my sync speed at 250. How do I know what ND filter is needed and are they all created equally? Any info would be very helpful

 

[tirediron]

You will need to know what your base exposure is, and then 'work backward' to calculate the number of stops of ND you require. I think for convenience, I would be tempted to go with something like a Singh-Ray Vari-Grad. As with any other gear, they are most definitely NOT all created equally; Lee, Singh-Ray, B+W and Heliopan are the top names; Cokin, Tiffen and Hoya are decent (usually) and most of the other stuff isn't worth buying.

 

[astroNikon]

basic information --> Neutral density filter - Wikipedia the free encyclopedia
if you pay attention to the "f-stop reduction" column you can get a better idea of which to use specific ND filter to use.

The fixed ones are identified various ways, such as:
ND2
ND 101
ND 0.3
which are all the same reduction (first 3 columns)

 

[SoulfulRecover]

Thank you both so much for the information and reading material