Picking the RIGHT strobe / light

[scubafish]

Ok all you officionodos I have a question:

With the invent of the newer SLR's (Nikon 90D and Canon T1 and many more to follow) shooting HD video as well as stills I'm a little perplexed on picking the right strobes for both scenerios. Some of the strobes on the market allow you to eluminate a continuous light but this is not sufficient for video as I've tried it in the past with unsatisfactory results. Does this mean when using this type of camera and housing that one has to take either strobes for stills or lights for video or carry BOTH! The other option is to take strobes for stills but only shoot video with ambient light. The last option will only work for 40' or shallower subjects and only during daytime light... I'm not fully understanding where this is headed for us underwater folk. I personally would like to flick a switch on my housing and shoot the same subjects as stills as well as some HD video with little effort while in the drink.

Any thoughts on this would be nice to know. Jim may touch on this at next month's meeting...

Thanks.

[TomC]

I think that we are just as much in the dark  as you are.

[Webster]

Underwater video is usually shot using ambient light and either a red filter and automatic white balance or a red filter and manual white balance (preferred) to get the correct color spectrum.  The video camera automatically adjusts the exposure by adjusting the aperature and/or the frame speed used to capture the images.  I have seen some examples of video shot with the Canon 5D MkII (see the Backscatter website) using ambient light (bright sunlight in shallow water) with good results.

In deeper water, manually white balancing the DSLR would be needed.  I am not sure about the use of a red filter.  Something to experiment with, I think.  Also, I don't know how a DSLR manages exposure in video mode.

Even the most powerful video lights (outside commercial movie making) will only illuminate a few feet underwater in daylight conditions.  They become more  effective at deeper depths, where it is darker, or in cracks and crevices.  Hauling them around in addition to the strobes used for still photos doesn't make much sense - get a video camera if you want to do that.  However, a powerful focus light (the Hartenberger Nano, for example) can provide local illumination on small subjects, and you probably have one of these on your housing already.

I am making a presentation on vidoe at the September 14 meeting, and I can explain more about how video works then.

[Webster]

I have just gone back and read the Backscatter web page on the D5 MkII, and there is a lot of information on it regarding exposure control and white balance.

It is at http://www.backscatter.com/5d2/.

Must read for anyone interested in video on the DSLR.