Strobes vs 45 degree shutter angle

[Adam Larsen]

I have a shoot coming up involving dancers jumping through a thin "wall of water". Most likely we'll be shooting with an SRIII @ 150 fps on 7205. We have a decent budget, so renting Unilux strobes could be a possiblilty. I've never worked with them and wanted opinions on whether or not the extra expense and potential difficulties are worth it (vs. manipulating the shutter angle).

 

We want the dancers and water to have as "crisp" a look as possible. Does shooting at 45 degrees look anything like the "strobed" footage I have seen commercials? I'm a little nervous working with the strobes, metering, etc., but would be interested in using them if they are the only way for us to get the look we want.

 

Any help would be fantastic,

Adam Larsen

[David Mullen ASC]

Well, at 150 fps with a 45 degree shutter, that's 1/1200th of a second per frame, so the only two reasons perhaps to use strobes is if either: (1) you want even shorter shutter speeds but still shoot at 150 fps; and/or (2) you don't have enough conventional lighting to achieve a stop with a 1/1200th shutter speed.

 

I don't have any experience with strobe lighting so I can't tell you how hard it would be.

[Rolfe Klement]

All depends on your definition of the word "crisp"

 

But as David says a 45' shutter at 150 is going to give you very broken up crisp movement but it will not be as still frame by still frame that the Unilux will give you.

 

The other big issue is going to be light and power - lighting to a decent stop at 150fps with 45' shutter - your dancers are going to get pretty warm and so is the water. I once directed a ballet shoot with a DP who brought in about 200k of light - we had three runners wiping sweat off dancers - it was the middle of winter and everyone was dripping sweat - and our studio electricity bill was about £500 a day. The producer lost about 5 years when we saw the meter readings at the end of the first day :-)... and we only shooting 75fps at 90' shutter

 

Metering is not a problem - just meter as you would stills flash photography - but speak to the rental company - they will always be a huge help

 

thanks

 

Rolfe

[Eric Steelberg ASC]

Remember that with strobes you are exposing for the flash of light and no the shutter or camera speed. Your exposure at 24fps 180º would be the same at 150fps and 45º because the stobe flash is so short...1/100,000 of a second. So because the flash duration will always be shorter than the camera based exposure, you only need to meter for the strobe.

 

Clairmont also has some strobes too:

http://www.clairmont.com/spec_items/cci_strobes.html

[Adam Larsen]

Thanks so much for the help. I talked with the people from Unilux today and I think I'm going to try to work with the strobes.

 

Adam Larsen

[Rolfe Klement]

tell us how it goes and post some images when done

 

thanks

 

Rolfe

[Sam Wells]

One advantage of using strobes is you can mix some "continuous" light in if you want to.

 

-Sam

[Robert Edge]

Just curious to know if you are going to have someone from Unilux on set to operate the equipment. My understanding is that they recommend this, although it is not essential.