Stop motion strobe - DPChallenge Forums

02/13/2008 09:21:18 AM · #1

I would like to catch someone in mid-jump. In doors using strobes (only). I have a 580EX and 430EX. I would like the person to be crisp and lit.

Do you think this is enough light power? Would a third strobe seal the deal?

I am thinking ISO400 f8 would be a good starting place settings-wise.

I tried to find challenge submissions of indoor jumpers, but didnâ��t succeed.

Can anyone help me out here? Examples would be great.

ralph

Nikon Z9

02/13/2008 09:33:11 AM · #2

speed not aperture
try the fastest speed you can sync at
unless wired multiple strobes may not work
(delay in recognizing the trigger may be longer than your sync speed ..)

Canon EF 24-105mm f/4.0L IS

02/13/2008 09:53:51 AM · #3

Ralph,
Good point about the trigger delay - I was not even thinking in that direction. I am not sure about using my fastest sync speed... I am afraid that if I do so, the subject will not receive enough light.

Is there anyone using my flash setup (580ex as master to trigger 430EX as slave) that has managed to get a good stop-motion jump in doors?

robs

Canon EOS R6 Mk II

02/13/2008 09:59:05 AM · #4

If your sync is not fast enough (don't use FP)... then darken the room. The length of the flash is VERY fast, so you need to minimise the light before/after the flash when the shutter is open. You might try 2-nd curtain so any motion is trailing into the crisp image...

Canon EF 24-70mm f/2.8L USM

02/13/2008 10:02:20 AM · #5

Robs: More good thinking. If my attempt to freeze fails, I will use 2-nd curtain sync as a next-best solution - good idea.

dwterry

Canon EOS-1D Mark III

02/13/2008 10:09:10 AM · #6

How far away will the subject be? Those flashes should be plenty of power unless your subject is far away. And unless you have lots of ambient light, the flash should do fine at freezing the subject regardless of shutter speed (because the flash exposure is much shorter than the shutter speed). The advantage to a high shutter speed will simply be to get rid of ambient light and potential blur caused by ambient light.

idnic

Canon EOS-60D

Canon EF-S 17-55mm f/2.8 IS USM

02/13/2008 10:16:19 AM · #7

I shoot people jumping in my studio pretty often. I use 4 strobes, but you should be able to do it with speedlights. As others have said, you want your fastest shutter speed possible, also you might bump ISO up a bit if the light isn't quite strong enough. Shoot in burst mode and expect to shoot quite a few before you catch that perfect moment when they are not jumping up or falling down, but instead are "hanging" at the top of the jump. I warn my models beforehand about letting their arms fling out in all directions (it often causes arms to get cut out of the shot) and I remind them to look at the camera and try to smile (most people giggle when they jump).

Hope that helps.

02/13/2008 10:22:21 AM · #8

David:

You mentioned that a fast shutter speed would not be required. That was part of the reason I asked my question. I remembered someone (very likely you) mentioning that same thing before.

I will be 6-10 feet from the subject (I would consider that close).

I will have some ambient light that I can't control - light coming through windows that have closed blinds. One of the windows I can totally cover, but the other is much to large to cover (but will have closed blinds as I mentioned).

I will do what I can to up my shutter speed to reduce ambient light being exposed.

What do you think about possible delay between master and slave - will that hurt me?

Thanks

Tez

Canon EOS-5D Mark II

Canon EF 85mm f/1.8 USM

02/13/2008 10:33:35 AM · #9

Ok,

I did the same thing with 2 Vivitar 285s on 1/16th power.

I got this:

[thumb]629156[/thumb]

and this:

[thumb]629273[/thumb]

This was at 1/200 shutter speed (my fastest sync) and around f/5.6. The only thing you need to worry about is getting the focus correct. I was in total darkness so i did this by holding a light source (mobile phone) about 18 inches from the face so the focus picks it up, then switch to MF so the focus is locked. This saves problematic focussing in low light.

Olympus 12-40mm f/2.8 Pro

02/13/2008 10:46:28 AM · #10

Thanks Tez. Yea - I was planning to focus just as you described.
You certainly stopped motion with those. But I would like more light on my subject. Perhaps stopping down and upping ISO would have allowed more light on the subjects (?)

Ann

Olympus OM-D E-M1

02/13/2008 10:48:59 AM · #11

You should have no problem freezing the people with strobes. Set your shutter speed to the fastest speed it will sync at. If you're using wireless triggers, it may not be the max sync speed on your camera, so you'll have to test. Then adjust your aperture and ISO without the strobes, so that the room is dark, or at least a couple of stops underexposed. It depends on the look you're going for. Then set up your strobes, and adjust the strobe power so that the lighting on the subject is correct.

If you get subject movement, there are two possible problems. Either the background isn't dark enough, or the flash isn't short enough. If the background isn't dark, your subject will be stopped, but have translucent edges. Go back to step 1 and adjust ISO and aperture to get a darker background. With humans, the flash should be short enough even on full power, but if it isn't, you'll have to adjust the flash power down, and readjust the ISO and aperture settings to let in more light. And probably darken the room some more.

edit to add: If you want the background to be lit, you'll have to light it with a flash, too.

Message edited by author 2008-02-13 10:50:07.

ralph

Nikon Z9

02/13/2008 11:22:48 AM · #12

here is a good discussion on flashes & speed
though they speak mainly on drips it can be extrapolated

Tez

Canon EOS-5D Mark II

Canon EF 85mm f/1.8 USM

02/13/2008 11:26:20 AM · #13

Originally posted by Bernard_Marx:

well, you could get another light in front for sure, or boost the ISO to compensate. Hell you could even do something in PS if you really liked but i was trying to black out the background completely so went to 5.6/6.3 to ensure this.

A light from the front may have helped, but I didn't want to jump onto anything, or be blinded when i was trying to land and potentially misjudge.

02/13/2008 03:36:55 PM · #14

Thanks Cindi and Ann. I honestly do appreciate all of this information!