I recently obtained a Beseler 4x5 Press Camera ( http://camera-wiki.org/wiki/Beseler_4x5_Press_Camera ). It is a really interesting camera, and I haven't used it much. But I am looking to have it replace most of my equipment soon. It has a focal plane shutter built into it like a speed graphic as well as a leaf shutter in the lens. However, I am not familiar on how to operate the focal plane shutter on this camera. Sure, I can use the leaf shutter on the lens currently on it, but I would like to use some barrel lenses, and I will need the focal plane shutter for those. I have used one similar to it on a century graphic, but this one looks different and I am worried if I start twisting knobs and playing with it I am going to break it. Does anyone happen to have a manual or anything for this uncommon camera that will tell me more about how to use it or specifically an instructional on how to operate it's focal plane shutter?

Thank you very much for your time.