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100 fps Synch Strobe Flashes

Published : 16th January 2004


I have a night shoot where I am emulating the Paparazzi effect of multiple camera flashes firing during each take. The Director would like to shoot at 100fps so I am thinking about how to generate long flashes, or how to sync the flashes to the shutter. I read that Theo van de Sande synced strobes for the opening of Blade, where he also used a short exposure to great effect.

The shots will be frozen at some of the flash points. I'm also fairly sure that I've read here at some point about Lighting Strikes 'Paparazzi Units' for exactly this purpose, but no-one seems to have heard of them.

If I have four or five Terra-strobes firing at maximum I'm sure something will register but I'd like to be a little more accurate than that. I'm on a Panavised SR3 HS. Can't seem to find anything in the archives, any advice would be much appreciated. Thanks.

Kind regards

Shane Daly
Director of Photography, London
http://www.shanedaly.co.uk



Shane Daly wrote:

>I have a night shoot where I am emulating the Paparazzi effect of >multiple camera flashes firing during each take. The Director would like >to shoot at 100fps

Recently did something very similar only we shot during the day ( gray overcast in NYC) 5274 stop was around 4- 5.6 most of the time. I also wanted a paparazzi effect so I got 4 Lumidyne flash heads with back up batteries. These are switchable 100,200,400 watt seconds for the output. Widest frame was a medium shot, waist up or waist down and I had the strobes manually fired from various angles according to the needs of the shot. I had the Strobes were reading f16 and sometimes 22 at the 400 w/s setting. They read really well on the subject and their randomness made a very credible paparazzi effect. These particular strobe units had a sync box with them that we decided not to use that would allow the strobes to be ganged together and sequenced to a degree, but not to the shutter on the 435.

If you want to see an effect where the strobe event ramps up from 0 to full intensity in slow motion then you would need a longer duration flash, like the output from the disposable flash bulbs used 40 years ago or the fabled paparazzi units from lightning strikes.

I think the strobe units I used cost all of $150 to rent for the day for my shoot. I would ring up a photo rental place and kick around some ideas with their techs. A relatively small amount of money and some free hands can create your effect.

Least of your worries is getting the strobe effect to register, unless you go for a narrower shutter angle than 180. As the shutter narrows, you have less chance of seeing the strobe effect.

Mark Smith
Oh Seven Films
143 Grand St
Jersey City, NJ 07302



>If I have four or five Terra-strobes firing at maximum I'm sure something >will register but I'd like to be a little more accurate than that. I'm on a >Panavised SR3 HS

Hi Shane --

If they are like the Terra strobes I've used (or D50's, D150's or HyperFlash) they're limited to 10 flashes per second. You can get great effects but at 100 fps....well maybe if you staggered all 5...the point is with 172/180 degree shutter you'll get pretty much 5 flashes max per realtime second on film...so @ 24 one unit would give you ~ one flash on every 6 frames.. @ 100 this is like one per second of screen time per unit...do the math.

I've done this with several units & individual controllers, and also with DMX but I've been burned with DMX - suggest you thoroughly test at the rental house if you go with DMX, frankly a few PA's is simpler in my mind.

The Lightning Strikes solution sounds more controllable and elegant, but rock strobes can work. I don't know if you'd have shutter edge issues with the HSR @ 100 - probably minimal to invisible...

Bear in mind, what you see in the vf is what you're not getting...I've found it helps a little to tweak a variable speed control on the camera as you're running.

Also if you use Terra strobes especially be careful of lamp position and ventilation, believe me..

Sam Wells



Thanks very much to Sam Wells and Mark Smith for the feedback. I ended up with two Paparazzi Units and two Terrastrobes, the combination worked really well. The solution of original flashbulbs was vetoed on cost per bulb but would have worked very well also.

Thanks again

Shane Daly
Director of Photography


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