difference between ND 8 and ND 4 filters?

[fairy bombs]

Hey folks.

Just looking at some ND filters,many say the ND 8 is very useful,so I might get one soon.

But what about ND 4 filters,what are they used for,I have seen many lovely rainforest creek

images,and the photographer's have used the ND 8,not sure what a ND 4 is used for.

Should I get both?or just the ND 8

Thanks FB

[Big Pix]

difference is 1 stop............... and used the same as ND8 or with the ND8

[reaction]

1 stop, and if you don't know what they're for, maybe you shouldn't buy one until you do.
not that you look like $ is an issue with all that gear!

[keefsmit]

Hi, I have used Nd8 filters for making scenes darker so I can obtain the correct exposure at slow shutter speeds. For example, to photograph ocean waves so they will appear blurred when falling over rocks at a 1/2 sec and still have an aperature of f16 for depth of field. It would be similar for waterfalls etc on a well lit scene.