LF shutter flash question...
I'm going to try to shoot a cheetah at full run with my 4x5. No kidding... I'm going to try it. Anyway... I will have two speedlights on remote near the track with the sun behind and left of the subject. That makes a great kicker with the dust he kicks up. My question... Can I use the faster shutter speeds (1/500) without a sync problem? I've thought about how the shutter works and I don't see how it would be a problem but I could use some reassurance.
Re: LF shutter flash question...
Should be no problem at all except having enough power.
Ian
Re: LF shutter flash question...
Leaf shutter, yes. I routinely use a Copal #1 (top speed, 1/400) with electronic flash for macro work out-of-doors. The flash stops motion, overpowers ambient. And I have full control of the lighting.
That said, make sure that your flashes give short enough flash duration at full power. I mention this because I have a nice portable Agfa 643CS whose duration at full power is 1/200.
Re: LF shutter flash question...
Full power for Nikon Speedlights is about 1/1000. My fastest shutter speed is 1/500 on one lens and 1/250 on another. That leaves plenty of open time. Thanks for the reassurance guys.
Re: LF shutter flash question...
You need to check out the guide no's and the combination using 2 flashes, that relates to distance and f-stop, your shutter speed is irrelavant except for balancing daylight & flash.
Ian
Re: LF shutter flash question...
The cheetah run was canceled due to weather. I'll get another chance in a couple weeks I hope. At least that gives me time to plan it a little better.
Re: LF shutter flash question...
Well done for being different and taking on a difficult assignment!
I started out buying Nikon Speedlights for a studio setup to take photos of my kids. I now have 3 bowens 1500WS flashes and 2 Bowens 1000WS flashes.
I measured a Speedlight at around 70WS I think...
I wholeheartedly wish you good luck in your quest.
Re: LF shutter flash question...
Quote:
Originally Posted by
Jehu
The cheetah run was canceled due to weather. I'll get another chance in a couple weeks I hope. At least that gives me time to plan it a little better.
Don't just plan; test! Theory doesn't always apply to actuality. If flash sync is off a millisecond or two at the highest shutter speeds, it will have a big effect on the results. Better to have a motorcycle as a stand-in for the cheetah until technical problems are solved than to schedule a reshoot. In theory, at 60mph the cheetah would move about 1/4 inch at 1/400 second with a perfectly efficient shutter. However, the blur will be greater due to the opening and closing time required by the shutter. Strong ambient back lighting may have an undesired effect on legs moving much faster than 60mph.
Re: LF shutter flash question...
All very true Jim. I was hoping to get an angle on the Cheetah just after a turn. He'll be down to about 30 mph or so at that point. I'll also be in front of him so the motion won't be that noticeable.
Steve, that's a pretty good idea. I was going to use a dog at the park but he won't be moving quite fast enough. I like your motorcycle idea.
Re: LF shutter flash question...
Curious - how are you timing the shutter release? Will it be a fairly wide shot and done by hand? Seems like you could rig up a little infrared trip system if you want to try a tighter crop. But I suppose cropping a normal/wide shot would be a lot easier...
Sounds like a fun project! Post some photos for us once you get some!