I have a small studio in my downstairs area.Do mostly portraiture and wedding photography.I have shot many photos in my studio and usually do good amateur work.However, I recently purchased new lighting equipment and ever since you would think I had never picked up a camera!I am shooting with a Canon Elan7 SLR film.I have a 420 speedlight on my hot shoe which I bounce from the ceiling.I have a medium softbox as my main light 45 degrees on right of camera (ps-300) and a light w/umbrella as my fill light 45 degrees left of camera (ps-300).I have a background light to background behind subject and a medium softbox hair accent to left back of subject on side of fill light.I have checked lights and all are flashing with trigger from speedlight flash.I have moved them in closer to my subject.My batteries are good in my camera.Yet the last 3 rolls of film I have shot at different times has returned from the developer "unable to develop.Too dark" I am at my wits end. I have loved photography forever but this is making me consider taking up candle making as a hobby!!! Can you help me??