Guys I have one of these matte boxes I am using with an XF300

Matte Box I (Professional Edition) - Matte Box I (Professional Edition) Manufacturers & Suppliers (http://www.wondlan.com/product/260-matte-box-i--professional-edition--wondlan-c4c5/)

The first time I tried using one of my 100mm filters, I can see the edge of the filter holder on the edge of the frame when fully wide. I can't get the matte box any closer to the camera because it fouls on the quick focus sensor, and I am loath to start cutting the matte box in case I need to sell it and go another route. I am only tying to use the rear most of the two filter slots.

I can't see a fix for this, so I am wondering what any of you guys are using successfully (with filters) on XF300/305s ?

Well I've found a kind of fix, but not using the matte box. My main supplier gave me an old style, deep rimmed, 82mm filter that had a broken filter glass. That gives me enough depth to attach my 100mm Formatt filter holder to the front of the camera. I am currently using a Tilta adjustable arm to mount a French flag in place of the missing lens hood, but I'm looking for a lighter, and more flexible arm to hang the flag from. There is no trace of a vignette.

Incidentally, the original problem produced the best example of rolling shutter I've ever seen. The edge of the filter holder was just visible on the frame edge, but panning one way would cause it disappear, and panning the other would cause it to creep further into the frame, and back to normal when the panning stopped.