Recently I had the opportunity to drive to Covington, KY – just on the other side of the famous Roebeling Bridge from Cincinnati Ohio. Designed by civil engineer John Roebling, it was completely in 1867 and its 1,075 foot span made it the longest bridge in the world.

Near the base of the bridge on the Covington side is a monument to John Roebling – and I wanted to take a photo of the statue with the beautiful, historic bridge in the background.  The warm colored lights that trace the structure of the bridge are stunning so of course, I wanted to take the shot after sunset.  But how do you properly expose the black statue and the illuminated bridge in the background?  The answer was a simple technique called slow sync flash.  Before I discuss the technique, I’ll share the equipment I was using:

THE GEAR

• CAMERA:  Canon R5 Mark II
• LENS:  Canon RF 24-70 f2.8
• FLASH:  Westcott FJ80 II
• TRIPOD:  Benro Blackbird Pro

THE TECHNIQUE

Essentially what you’re doing with this technique is exposing your foreground subject using the flash, and exposing for the background using a slow shutter speed.  But to do that, you first need to meter for the correct shutter speed.  The easiest way to do that is put your camera in aperture priority, set your ISO to 100, pick an aperture setting, and take a photo without the flash.  The camera will select the the correct shutter speed based on the available light.  In my case, I started at f8, and my test shot resulted in a shutter speed of only about 4.5 seconds – not long enough to get the background exposure I was looking for.  So I stopped down to f16 resulting in a shutter speed of 15 seconds – a perfect long exposure time for the bridge.  Next I turned on my flash (in TTL), went into manual mode, and set my aperture to f16 and my shutter speed to 15 seconds.  This combination provided me the needed illumination of the statue with a fantastic long exposure of the bridge – with beautiful sun stars on each of the bridge lights.  Give slow synch flash a try the next time you want to take a low light portrait with lights in the background – just make sure I get a subject remains still during the long exposure.