Capturing Motion Blur in Studio?

[soconnor]

**Originally had this in another section, but agreed it might be better here.**

I’ve been devouring the info on this site for a while now (thanks for the great discussions!), but this is my first time posting.


I’m looking for tips on capturing color motion blur on a white background. I’ve been fairly successful with a black background, but my initial tests with a similar setup and a white background left me less than enthused, so I’m hoping someone out there who knows more about light will point me in the right direction.


Here’s the setup info and an example pic. Essentially, it’s a four second exposure with a “controlled ambient light” (my phrase and probably not a very good one) and two speedlights to freeze the movement at either end of the exposure. White blur comes through beautifully, or course, and colors (provided they’re on the lighter side) show nicely as well. But when the background is white, the blur is faint and drab, no matter what shade of color I try.


What I’m hoping to capture is bright blurs of color between the two ‘frozen’ poses. Any thoughts?

Thanks in advance!

[zagiace]

With a black background it is easier to control the light and avoid contamination.
not sure if this would work but...
I would try:
Having 4 lights, 2 in front lighting the subject but flagged and 2 using modeling lights only to light the background. Gel wither the background lights to match the flash or the front lights to match the background. With a white background light will be bouncing everywhere, controlling the spill off your primary light source will be the key. Flag the front lights as to not spill on the background.Drag the shutter to closely match the modeling lights of the background and use that as your base exposure. Match the power of the front lights to your background lights exposure.
Using a lot of space, a long seamless and a lot of subject to background distance may help.
The tough part is going to be getting the background to remain white throughout the image.

[René Damkot]

The background, if white, will "burn through" the ambient image.

You might try strobing the flashes (on the BG): Then the model will cover (part of) the BG when the BG flash is fired, while being lit by ambient... Will be a different effect though.

What you get here with a black BG, cannot be done against a white BG...
Think of it this way: Color + white = white. Color + black = color.

[c2thew]

this is super cool. so basically you just pressed the test buttons on the speedlights throughout the sequence?

[René Damkot]

As far as I see, (and from remembering the older post), the flash was fired twice: At the end and the beginning (left & right). The "mid section" is lit by ambient only.

[Gentleman Villain]

Basically - shooting motion blur on white is the opposite of shooting motion blur on black. ON black the motion blur is most apparent outside of the silhouette edges of the subject....On white the motion blur is most apparent inside the silhouette edges of the subject. Hope that makes sense

The fun thing about capturing motion blur on white is that it's possible to freeze the silhouette of the subject against the background by using flash to light the white background.....Then use continuous lighting for the subject and drag the shutter to create motion blur inside of the silhouette.

For example....Imagine that you're shooting a headshot....The background could be lit with strobe and freeze the silhouette of the subject's head against the white background....Then a single continuous spotlight could be used on the subject's eyes...The eyes that are lit by continous will be blurry if shot with a long exposure...but the silhouette area around the subject's head will be perfectly sharp. It can be a way to make a subject look whispy by making parts of their body perfectly sharp and other parts blurry. Depending on the subject and it's treatment...the effect can be either angelic or creepy but always mysterious

[SYS]

Gotta give this cool technique a try... :)

[soconnor]

Wow, great info all around, thanks! I had a feeling it was going to be a very different kind of beast than with the black bg...

I'm curious to see what can be done with some of the techniques mentioned. I'll be sure to post the test results.

And Rene, you're right, but there were two strobes- the first triggered manually immediately after the shutter, and the second handled by the rear curtain sync function to capture the very last moment.