June 29, 2011

The Drag Flash Focus Pull Of Yesterday.

Remember the good old days, laden with chemicals, film, and little calices on your thumb and forefinger from loading too many Hasselblad backs?  In my class last night, I got off on a bit of a tangent (not entirely unusual) and we started talking about the topic of pulling your focus during a mixed light exposure.  I’m honestly not sure if it has a formal name or not, perhaps I just coined it, The Drag Flash Focus Pull Of Yesterday.

At any rate, if you are old enough to have has a cassette deck in your car, then you probably recognize this effect from days gone by.  It’s remarkably easy and gives the photographer the ability to create a unique look, quickly and all in camera.  Perfect for a quick portrait or editorial shot.

You need to be able to use a light your subject with strobe and use either existing light or tungsten ‘hot’ lights on the background.  The only other two requirements are your subject needs to have zero light falling on them except for the flash and your background exposure should be around a full second.  If you can’t get these then the technique will not work.  

Once you have your foreground and background lit, make sure no background light is bleeding over, on-to or otherwise hitting the subject.  This is easily done by making an exposure with only the background lights on; do not let the flash fire. 

If everything is working properly the resulting images should place your subject in complete silhouette.  If she (rock star student Sarah Linder in this case) is, then you are ready. 

detail showing the effect
Plug in the sync cord and focus on your subject, once you release the shutter, gently roll the focus to infinity.  I forgot to tell you, if you are shooting digitally, you have to take the camera out of auto-focus mode. Rolling the focus to infinity while you are exposing the background causes your subject to increase in the frame ever so much.  This slight increase in size actually masks, or covers the background immediately around the subject.  The faster you pull the focus the larger and less saturated the line.  A subtle roll of the focus ring will give you the thinnest of black edges.  Quite complementary in most cases.

If you reverse this action and start with the subject sharp and after the flash fires, you pull the focus to the near focus on the lens, the subject will shrink ever so much in the frame revealing background that was initially masked by the larger subject.  The resulting effect appears as if the background is bleeding over or onto the subject. 
While I prefer the black line 10-1, both techniques are easy to create in camera while you are shooting, giving you a unique look that requires zero retouching or post time.  Here are some detail shots.  

I should also mention the the light used to illuminate Sarah was a custom Canon 580EXII modifyer made by Modern Alternative student Chris Bellezza.  If you are totally digging this, this and more can be found on page 107 of my book, Digital Photographer Lighting for Dummies.

Have fun!!

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