...and the first novice is ME! I've used a Cokin-P (85mm) slide-in filter system on lenses not as short as I now have, but that holder intrudes into the images of lenses of 24mm and shorter on FF bodies. After talking with the nice people at 2filter.com in New Hampshire, I bought the Hitech 100mm starter kit.
http://www.2filter.com …h4x5GradualholderKIT.html
Here's what arrived, VERY quickly, I might add. We have the 77mm adapter ring, modular holder, extra screws and nuts, and 3 graduated neutral-density, 100X125mm (4"X5") filters. The kit comes with 1-, 2-, and 3-stop filters.
Here's some detail of the front of the holder with the 3 original holderclips installed.
The 3 holderclips will hold 2 filters; if you slide a filter in the rear-most slot, it would not be held tightly and would fall out.
Here's detail of the rear of the holder. The thumbscrew tightens the holder onto the adapter ring.
Some detail of the adapter ring, loose...
...and installed in the holder.
The ring can be installed on the lens and then the holder slid onto and tightened onto the ring, or the ring can be kept clamped in the holder and the combined assembly screwed onto the lens.
The screws holding the holderclips onto the holder plate can be installed pointing forward or rearward, but pointed forward they intrude into the image at 22mm and shorter with my 17-40.
Here's the front of the holder with 2 holderclips installed, screws pointed rearward, and one filter started into the holder.
Here's what it looks like on the 17-40.
This stuff appears to be made very well and plenty strongly, and the extra screws and nuts are appreciated, as they're small and easily lost in the field if you chose to change the holder's configuration.
I hope this helps other novices at slide-in filter systems.
