After Purchasing a Lee Big Stopper and already owning a Cokin Z Series Pro filter holder. When I ordered the filter i didn't realise that it came with a foam seal to stop light leaking through. I was immediately unsure whether it would fit in my holder which is designed for 100mm square filters.
So i thought id post it on here to say what i have come up with and how the filter holder can be changed to fit the filter.
Firstly i have a Tokina 11mm - 16mm wide angle lens which also is a diameter of 77mm.
The Coking filter holder has one section at the back where the lens adapter will fit then the other side of the body there will be three separate slots for filters along with little pegs that tend to get in the way.
I found that the cokin Z series pro holder is actually large enough to allow the lens to fit through therefore the lens adapter can be used in the first on the three filter holder sections (with the lens through the holder) rather than on the back in the single section. The Lee Big stopper that i ordered is 100mm square and will fit right in front of the lens and hopefully the foam wont interfere with the photo (i have not tested this yet although it looks promising.)
This will also help with vignetting on the corners with the holder being in the way, i have found that with the Z series pro holder and a tokina 11mm - 16mm the holder interferes with the picture when its at the widest angle (this is when the lens adapter is positioned in the single holder section which would be the back of the holder). With the lens adaptor in the first of the three filter sections the holder does not interfere with the photo. This would mean that you could only use 2 filters instead of three.
Hope this helps
Any questions about anything please don't hesitate to ask.