Wednesday, October 7, 2009
Slow shutter speeds and fire
Now surely a fire is one of those times that you need a fast shutter speed? After all you have to capture all those sparks firing out of the top.
That's what I thought and had the shutter speed cranked up to 1/1000th second and you know what I got?
A whole bunch of pin pricks of light coming out of the top of the fire and no volume to the flames. Hmmm time to put the thinking cap on.
The shutter speed was so fast that it wasn't recording the fact that the sparks were moving on erratic paths out of the top of the fire, it was only recording them in a brief moment of that passage. In other words it was freezing the motion when in actual fact what I wanted to do was show the motion. And the shutter wasn't open long enough for the big flames to record properly in the picture.
So I put my shutter speed down to 1/15th second or thereabouts and suddenly my flames were creating paths and patterns through the night sky out the top of my sugar cane fire and my flames were full.
There was only one problem - or in my case lucky observation. This picture was shot on film. I had no idea what was happening at the time. It was all a lucky guess basically, although I like to think there was a bit of skill involved!
After taking 10 or so shots at the faster shutter speed I suddenly realised I was doing things the wrong way. So I backed off on the shutter speed. How did I know to try for 1/15th second? I didn't. And that's the beauty of those slow shutter speeds. It's all a guess. At least with digital you can adjust things on the spot if you're too slow or fast.