Reflex Viewfinder Metering

[tiberiustibz]

So I own a Bell and Howell 670 XL which I destroyed trying to modify it to max 8 and a Braun 105 XL S which contrary to every source I've seen seems to have a 24 FPS setting (perhaps a post production mod?). Anyways, the first thing I noticed both when trying to film indoors and in the poorly translated manual was the all important reflex factor, whereby when the TTL viewfinder steals light from the film path. Does anyone know how much it loses? I believe it to be one stop (half the light to the viewfinder). As such the "focus free" bell and howell with its separate viewfinder performs better than the Braun in low light. Does anyone know of any cheaper cameras with the "guillotine" style shutters which transmit all the light like the beaulieus? Does anyone know for sure so I can use a handheld meter in low light?