High Speed Sync – Attempt #2
My first attempt at using high speed sync in midday beach shoot was a fail. At f/2.8, iso 50, 1/8000 the sky was the perfect deep blue tone I’d like it to be. The flash power of my 500ws Profoto B1 strobe wasn’t enough. The subject was underexposed.
High Speed Sync
I won’t get into the technical side, but in summary, most modern cameras and shutters (I’m shooting a Canon 5dmk3) the sync speed is 1/200, anything faster there will be black bars on the bottom of the image. With high speed sync it allows you to shoot up to the limit eg. 1/8000 without any issues. My einsteins had Hypersync, which allows you to shoot that fast but only at 1/1 full power. I didn’t get a chance to try it out. You can use ND filters to try to keep the shutter speed at 1/200 or under. This is my typical technique but I usually run into some issues with tinting in the ND filters or it’s so dark I can’t see through them properly.
As mentioned above my first attempt at HSS didn’t work, my 500ws strobes didn’t have enough juice. I believe you lose 1-2 stops of power using HSS mode on the B1’s and it only works at 8-10/10 for power. From my guess, my first attempt, I’m about 1-2 stops under exposed on the subject. So for my second attempt, I tried using the Profoto wide zoom reflector which adds I’m guessing 1-2 stops of power of light. So hoping this might be my solution for my HSS attempt.
The day was hot, I’d say over 34 degrees (registered 37 degrees on my car) bright midday sun, not ideal for shooting. I tried the technique at the end of my shoot, knowing I’ve got the key shots I wanted first before playing around with my gear knowing there’s a chance it won’t work.
Here’s an image of Sarah, sun slightly behind her to the left side of the camera. (my usual technique). The profoto B1 strobe left side of her, front with the wide zoom reflector. The camera settings are: f/2.8, iso 50, 1/400, 3 stop nd filter, Profoto B1 strobe with HSS activated. TTL worked perfectly and she’s properly exposed. The wide zoom reflector boosted the light power enough for the exposure. The background is properly exposed to the feel I was looking for.
Of course the other alternative is to shoot at golden hours (an hour before sunset or before sunrise) but with a small child, I can’t schedule these night shoots all the time.
Next post, I’ll post more about the images from this shoot.
Until next time!