Thursday, December 11, 2008
Shoot your honey! ...with High Speed Sync
Want to shoot a photo with flash in broad daylight and make it appear as if it were night time?
Well then, high speed sync is for you! High speed sync is when your shutter on your camera trips faster with flash than its native sync speed. All cameras have a "native" sync speed that it can trip at while using flash. Most cameras are anywhere between 1/200 of a second and 1/500 of a second. My Nikon D300's fastest native sync speed is 1/250 and my D70 is 1/500. I could go in to the technical reasons as to why this is, but I'll save that for those more experienced in this field (see links below).
To get your camera to shoot at faster than native sync speeds you have to do one of several things. The easiest way, and the way I utilized for these shots are to have a camera with a compatible flash that will allow high-speed flash syncing. My Nikon D300 will sync with my Nikon SB-800 and SB-600 at the camera's highest shutter speed which is 1/8000 of a second!!! I'm not too familiar with the Canon bodies and flashes but I suspect they have this option too.
On the D300, I go to the Custom Setting Menu e1 which is flash sync speed and I select 1/320 sec (Auto FP). In this setting, the camera will trigger the off camera flash (using CLS) at any shutter speed I choose. If I am shooting at 1/320 sec or lower, the camera will fire the shutter normally. ....normally? what's this you say?
When you are using high speed sync, the camera will send a signal to the flash via a light pulse from the pop-up flash that tells the off camera flash to fire in high speed sync mode. Then the flash will fire multiple pulses of light as opposed to one burst of light. The down side to this is that you lose a little more power than if you were shooting in non-high speed sync mode. Again there is a lot of technical info as to why this is, which you can read about in the links below. This post is more of a 'how-to'. And on the Nikon, that is all you have to do.
This is a really cool feature to play with and I am still experimenting with all of its practical uses.
The above photo was taken at f/3.8 at 1/8000 of a second at ISO 100. Its an ok photo, but the reason I like it is just the fact that I shot it at 1/8000 of a second, but the other benefit is that when you are trying to over power harsh daytime sunlight, most of the time (if you're not using high speed sync) you have to either stop your aperture down very low which gives you a large depth of field in your portrait. Sometimes this is ok and can look cool in the right situation, but generally most people prefer a portrait with a shallow depth of field. The other alternative is having big, huge expensive lights to overpower the sun. With high speed sync, you can get your shutter speed fast enough to nuke the ambient light and still have your aperture wider open to get that shallow depth of field.
The photo below was taken at f/5.6 at 1/500 of a second at ISO 100. I'm still shooting in high speed sync to get my aperture at f/5.6 and I like this photo better because I brought in just enough ambient light to use the sunlight as a kicker light (or rim light) on the edge of Jenn's hair effectively creating a two light setup.
This photo is more aesthetically pleasing to me but again, if I wasn't using high speed sync, I would have had to stop my aperture down a few stops which would have resulted in a larger depth of field.
I hope this helps you to understand high speed sync a little better, but for further clarification and much better technical information check out the links below.
*Strobist explains it and shows you the results
*A very, very thorough explanation of the why's and how-to's by legendary wedding photographer David Ziser on Digital Pro Talk ....there's a video with this link too!
Try this for yourself and have fun with it!
NOTE: A very special thanks to my girlfriend, Jenn for posing for these photos and all of the other crazy photos I've made her pose for, so I can figure out nifty lighting tricks. Love you hon! =)