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Ok so there was a previous forum thread regarding a rehousing project for the LA7200. Based off the video there, I have had this design in my mind for my own rehousing project and improvements as well for close focus and/or marrying the LA7200 with a manual focus lens and making an all in one lens solution for the Canon 5d Mark III.   Progress is starting off well. Getting the hang of AutoCAD and designing as such.   I am planning on first prototyping with a 3d printer I have access to then going to a further manufacturing step from there. Not trying to get too ahead of myself however you can keep track of the progress and id appreciate comments or suggestions regardless as I try to work this out.   Steps:   Design model in AutoCad --- 15% Port model into Google Sketchup 3D print prototype Test Prototype Test again.... Make changes... Probably test again.... Use AutoCad model for CNC machining Produce final model.   Planned features...   Close Focus and far focus at a twist of the ring. Easy to handle enclosure Focus ring easy lens adjustment Standard housing to fit Cokin P or other diopters much easier   Possible features   15mm rail mount auto adjusting focus solution Housing combined with Aperture adjustor on a Canon FD manual Lens Direct connection to the 5d Mark III basically making it a hack lens using a custom EF mount or 72mm thread AF confirm chip? (not a bad idea) All the lens flares! (ALL THE LENS FLARES!) Er multicoating removal. Something like that.   Close to exact Measurements via caliper - (short of cutting the existing enclosure in half. I could not get the measurements exactly for how close the back and front lens elements are in terms of distance)   Front Element - Concave Width: 84.90mm Height: 72.96mm Depth: 16.25mm   Rear Element - Convex Width: 52.96mm Height: 40.99mm Depth: 4.13mm   Front Element Holder depth - 17.82mm Outer Hood Depth - 13.14mm   Approx 23.8mm distance between the two lenses. (not entirely sure on this. Like I said, cant figure it out unless i cut the thing in half and really I want to be able to use it until the enclosure is finished at least)   All in all, working pretty well so far. Got the elements into AutoCad, and its time to start designing the enclosure for it.  

I have a question regarding the LA7200, basically in order to focus you would to move the back lens element or front. Would that be correct? Would it be possible to allow focus by adding another lens element behind the flat back lens element. Not sure how the image is presented by the square back of the LA7200. Im currently in the process of modifying it and frankensteining the lens with old junked vintage lenses to make it one whole lens that does not need a taking lens. Just want to make sure I have the physics right. Thanks in advance.