Hey. After recently purchasing a Hoya ND400 (awesome), I've been playing around with long exposure times. Now, I'm using a Canon EOS 350D, and I was wondering if there was any way of reducing the shutter speed to a value past 30 seconds? I'm sure you'll know that if you try to go for a longer time, it will display the message 'bulb'. What does this mean exactly? Any help is appreciated.