How was this shot?

[antigravity]

Ever since I came across this image, I've been wondering and experimenting on how to get the same effect..

http://canondigitalphotographycontests.fotopic.net/p21455975.html

Can anyone shed some light on this? :confused:

Thanks! :D

[robertwgross]

It looks like it was shot with flash (to expose the child) and with a long shutter of about one second (to get the sparkler).

---Bob Gross---

[antigravity]

Thanks!
I tried that a while ago, but I get too much of my arm blurring the image... any tips?

[thomascanty]

Thanks!
I tried that a while ago, but I get too much of my arm blurring the image... any tips?

Set the camera to use rear curtain flash sync so the flash fires at the end of the exposure instead of the beginning.

[antigravity]

ohhhh thanks! i'll try to play around with that :D

[munchy]

Set the camera to use rear curtain flash sync so the flash fires at the end of the exposure instead of the beginning.

How does that work then? Isn't the light on the sensor additive so it shouldn't matter when the flash goes off?

(been sitting here for 5 mins trying to think why your suggestion would work!)

Thanks in advance, Munchy

[DocFrankenstein]

How does that work then? Isn't the light on the sensor additive so it shouldn't matter when the flash goes off?
The sensor is the same as film if that helps

[MattyB]

it's a clever shot, and it came out well

i don't see how making the flash fire at different times of the exposure would make a difference, but i stand to be corrected.

you shouldn't get that much blur in theory - the flash will 'freeze capture' the anything in it's range (the child), then the sparkler would be the only light source from there on in on the exposure, so it would come up nicely.

if you're getting too much blur - you possibly have too much ambient/background light. try it in a darker section of your backyard, where you can't see the child through the view finder, only the sparkler (don't worry, the flash will solve that.).

also, use a tripod. the camera shake will serverly alter the circle blur that the sparkler makes.

good luck, show us the results :D

[munchy]

The sensor is the same as film if that helps

hmmmm.. not really....need a little more....brain working slowly today....

Still don't see why it should matter in this case, other than the sparkler 'rod' being at the end of the trail (rear curtain sync) instead of the beginning (front curtain sync).

Why would the arm would appear less blurred with rear curtain sync?

Munchy

[antigravity]

You have to do this in the dark, as little light as you can manage just so you dont fall over stuff :P

I tried playing around with it.. taken with a 20D at ISO200 with a 4 second shutter speed :)

http://img482.imageshack.us/img482/4276/img64170ri.jpg

Thanks for all the replies!

[thomascanty]

How does that work then? Isn't the light on the sensor additive so it shouldn't matter when the flash goes off?

The flash is what is illuminating the person. If you fire the flash with the first curtain, you'll still get the blur from his arm as he waves the sparkler around. If the flash fires with the second curtain (when the exposure ends), the person will be sharper and there will be less blur from the movement.

[MattyB]

well done :) you've got it down pat!

[MattyB]

The flash is what is illuminating the person. If you fire the flash with the first curtain, you'll still get the blur from his arm as he waves the sparkler around. If the flash fires with the second curtain (when the exposure ends), the person will be sharper and there will be less blur from the movement.
is that assuming that the child stops waving the sparkler by the time the flash fires?

if so, then where wouldn't be any hand attached to the sparkler circles

[thomascanty]

is that assuming that the child stops waving the sparkler by the time the flash fires?

if so, then where wouldn't be any hand attached to the sparkler circles

The arm doesn't have to stop moving because the exposure ends there. The flash fires, lighting up the person (with sparkler in hand), and the shutter closes. End of exposure. You get the sparkler circles from the first part of the exposure as the person waves it around, then the flash fires, putting the person in the picture as well.

Yes, you would get similar results firing the flash with the first curtain, but the residual light from the sparkler (and probably a little light fall-off from the flash) would result in a little blurring of the arm and hand as they continued to move throughout the exposure. With rear curtain sync, there is no more movement during the exposure, so the blur would be eliminated.

[antigravity]

The hand will not blur out because what registers on the sensor is the split second that the flash fires. My 20D automatically sets its shutter speed to 1/60 when I'm using flash, so I figure that for the duration that the shutter is open, only the last 1/60secs or so will register clearly :)

[thomascanty]

The hand will not blur out because what registers on the sensor is the split second that the flash fires. My 20D automatically sets its shutter speed to 1/60 when I'm using flash, so I figure that for the duration that the shutter is open, only the last 1/60secs or so will register clearly :)

You're supposed to do shots like this in manual or Tv mode so you can choose the shutter speed, not the camera. You can still use the flash in longer exposures. The camera will collect the light for the entire duration of the exposure, not just when the flash fires. I've done shots up to forty minutes long, using multiple flashes, headlights and flashlights.

[antigravity]

Yup! I shot in Tv mode :P

From what I gather, it's a simple matter of lighting up anything that you want to appear on the image.. So if for example, you don't want blurred traces of your arm in the image, you have to make sure that no light is on your arm while taking the long exposure shot.. In this case all I wanted in the shot was the light trails, so I had to make sure that the sensor picks up only that.. And then everything else is put into the image when the flash fires.. :P

Did I get that right? LOL
Thanks everyone!

[thomascanty]

Did I get that right? LOL

Sounds close enough to me. :)

[munchy]

Yes, you would get similar results firing the flash with the first curtain, but the residual light from the sparkler (and probably a little light fall-off from the flash) would result in a little blurring of the arm and hand as they continued to move throughout the exposure. With rear curtain sync, there is no more movement during the exposure, so the blur would be eliminated.

Cool, this makes a little more sense now, especially if the rear curtain sync prevents unwanted residual light from the flash. I would have thought that the flash pulse itself would have been shorter than the act of closing the shutter...but maybe not.

I'll have to try it and see!

Cool pics by the way.