sentences:  The camera was a commercial success at a very difficult time for the company, sales of the latest rangefinder Leica M5 had been very poor and the previous Leicaflex series had made little or no profit leaving the company in a precarious financial state, the R3's success seemed to indicate a new direction.For selective measurement the R3 used a secondary mirror with light cell in the base just like the Leicaflex SL.For integrated measurement two light cells were mounted on the viewfinder prism; switching between selective and integrated was electronic.