What am I doing wrong with my studio lights?

rwilliams · Dec 13, 2014

I'm so in over my head with studio lights. I used them years ago when I worked at a studio and purchased some of my own recently thinking I'd remember exactly what to do. My memory has seriously failed me because I just can't get it right.

I'm attaching an example, but in several of the first photos I took (deleted now), half of the photo would be completely black. Then, the other half completely fine. You can see in the one attached, the black strip going across the bottom. The higher I would cut up my exposure, the lower the line would be, but then the photos were more over exposed. I tried re-positioning the lights a dozen different ways and I still could not get it right.

Any suggestions or advice on what I could be doing wrong?

Braineack · Dec 13, 2014

shutter sync speed.

you should also watch your focus. why are you shooting at such a low DOF with studio lights?

rwilliams · Dec 13, 2014

I wasn't to begin with. I was just adjusting EVERYTHING trying to find something that would make a differen

Can you explain what is happening to cause the black? I just couldn't understand why it was doing that

Braineack said:
shutter sync speed.

you should also watch your focus. why are you shooting at such a low DOF with studio lights?

nk on t

480sparky · Dec 13, 2014

Even though he says the video applies 'specifcially to shoe-mount flashes', it still applies for monolights.

snowbear · Dec 13, 2014

The camera has a maximum speed with which the shutter will synchronize with the flash. If you go faster, you can catch the shutter as it opens or closes. That's is probably what the black is - the shutter curtain. I think the synch speed on the T3i is 1/200, so don't shoot faster than that.

The one you posted looks blown out to me, so you might want to think about an external meter, or at least take a couple of test shots first and check your histogram.

Trever1t · Dec 13, 2014

Yup, your shutter speed is too fast, the strobe is actuating faster than the aperture is open.

480sparky · Dec 13, 2014

Trever1t said:
Yup, your shutter speed is too fast, the second curtain is closing before the speedlight has a chance to fire.

Fify.

Village Idiot · Dec 16, 2014

Did anyone mention your shutter speed was too fast yet?

TCampbell · Dec 17, 2014

When you use off-camera flash fired by wireless triggers, the triggers may create an extremely small delay. It's not much, but it may be just enough so that if you run your shutter AT the "max flash sync" speed you will begin to get the shadow of the second shutter curtain beginning to close. If this happens, just slow down the shutter by the smallest increment (1/3rd of a stop typically) so instead of using 1/200th, you might be using 1/160th instead.

You wouldn't have this delay with shoe-mounted flash because the flash will fire as soon as it detects the camera triggering. But when using off-camera via a radio or optical trigger, the camera tells the hot-shoe to fire, but this is really picked up by your trigger which has to send the wireless signal to other units. Those other units are monitoring for the signal and when they detect it, they have to trigger their flashes. This means there's an extremely small delay for the trigger sender to react... and another extremely small delay for the trigger receiver to react... that's in addition to the extremely tiny delay that it takes the flash to react (which would be the same delay whether the flash is on-camera or off-camera.)