Hey all We've recently invested in a beautiful Cooke Series SVa convertible lens for our 10x8 field camera kit at work. Being able to remove the front and rear cells to change the focal length is super flexible, but is it possible to replace a cell with a protection filter, screwed straight onto the shutter, in order to protect the shutter / aperture blades? I'm a bit nervous about sending students out into the wild with exposed inner workings... Many thanks in advance! Tom.