Paul C. Buff, Inc. Technical Forum

I am using 3 Einsteins with softboxes in a small studio. I'm shooting with a Nikdon D90 set at ISO 200. Cyber Commander is set at ISO 200. The shuutter speed is set, maybe by default, on the Cyber Commander at 1/125 sec. How do I determne the best shutter speed in such a setup for glamour photography? On the Ken Rockwell site, he states that he uses 1/80 to 1/100 for portraits. As a newbie, using the D90 on manual, I'm a little lost on how to determine the best shutter speed. (I am setting the apeture based on the lighting setup and the value provided by the Cyber Commander meter reading for ALL.)

take a photo without firing the lights. Is it black? if so then you are fine. Just be sure to keep it at or below the sync speed of the camera. In low light, shutter speed is not that critical, as the ambient light is not enough to make an exposure difference from 1/30 (or less) on up. If you were trying to mix the ambient into the scene, then you woulod have to set shutter speed low enough to allow that.

As for motion stopping, the flash will handle that for you. Since no ambient light is exposing the subject, The the only light comes from the flashes. the t.1 time 1/550 or so on an E640 at full power. So if you open your camera up to 1/30 or 1/100 or 1/200, you will get the exact same exposure and action stopping in each, assuming a completely dark room, and all other variables remain the same.

Here is the rule of thumb I follow:

If your primary source of light will be from a strobe and you do not need any ambient light, set your shutter speed to the highest it will sync to your strobes.

Conrad

1/125 is the best sync speed for most studio use. Plenty fast to ignore the ambient light (including modeling lamps) and slow enough to avoid the dreaded black bars, even with most radio trippers. Outdoors, where you are balancing sunlight against flash, it becomes more complex.

To expand on what TS and Luap have said..............

Try having your studio at "normal" brightness, modelling lamps on, maybe the ceiling lights on and then take a photograph with your strobes OFF.

Try something like ISO 100 (200 for most Nikon users), 1/125, f/5.6 - 8 or even f/11 if that tickles your fancy.

Is the resulting image black? If not, lower your light levels (or stop down your aperture) and rinse / repeat.

When your ambient light is NOT affecting your exposure, you'll find having "ambient" light in your studio has advantages .......You save yourself a number of OH&S issues (no dark studio to trip over things), it's easier to find things that you have put down and maybe most importantly, your models pupils will not be all large and black, they will not be all "wide open" due to the darkness.

HTH,

AB>

Try this as an unofficial, but quick reference:

Once you've found your target aperture/flash power:
Highest Sync Range 250th - 200th = Flash Fill Only
Range 125th - 60th = High Flash, stops in a Lttle Ambient
Middle Sync Range 1/30th = Good mix or Visible Flash & Ambient (pics' BG may start blurring if handholding)
Range 8th - 4th = Mostly All Ambient (Where it mixes with Flash exposure)
Lowest Sync Range till 1 sec 1/1 = All Ambient

Hope this helps :)