100mm vs 150mm Filter Length

Hi Folks,

I'm soon going to buy a Lee Foundation kit and a couple of Hitech ND grads... my questions are this:


1) Is there a benefit to buying 100 x 150 ND grad filters instead of the 100 x 125 i.e. how much of the frame can I fill with the "ND" section of a 100 x 125? If it's only halfway, then I guess I should get the 150 length for shots when there's two thirds sky or something.... right?

2) If I could only start with 1 or 2 of the hitech ND grads - what should I go for? 0.6 and 0.9 and combine them if I need more? I read somewhere that a few folks use 0.6, 0.9 and 1.2 a lot and say 0.3 isn't really worth having (to start off with anyway).....


Thanks y'all!

1. ND filters are 100x100mm; 100x100mm GND filters don't exist. They are either 100x150mm (Lee and Singh-Ray) or 100x125mm (Hitech).

2. If you are starting out go with a 2-stop (.6) soft and a 3-stop (.9) hard.

Thanks for the reply / advice mate - most appreciated! - I've modified my post to correct the sizes.

I don't use Hitech filters, but if you are plan on using the filters on very WA lenses and FF bodies, the 100x150 will provide more flexibility.

I have a set of 1,2 and 3 stop grads and the most used one is the 3 stop, followed by the 2 stopper on rare occasions. I cannot remember when I last used the 1 stop grad. Shooting RAW I can cook the image in post processing that much.

I'm not sure I'd ever find a need for a 4 stopper.

I have the Lee foundation kit holder and have been using 4x5 Hitech GND filters for years...don't have any problems using them on my FF with ultra wide lenses. Never came across a situation where they weren't long enough to cover the frame. I agree with starting off with the 2-soft and 3-hard filters. A 1-stop is pretty much useless, at least in my opinion.