First studio experience

[Phonetic]

Hi All.

Having worked with natural light and flash light for some time, I decided to try out some studio lights. I got myself a Bowen's 250/250 kit and set op the lights in a standard 2 lights configuration (softbox main, umbrella fill, white background). I've read what I could here and gotten pointers / tips from lots of POTN'ers. They experience left me with more than a few questions unanswered tho. Please forgive my newbieness, but I’m trying to sort some basic concepts out. Here it goes.

Using a sync cord / or my 580 EX set at manual with 1/128 power I was able to trigger the strobes as intended. The ST-E2 was to no use as it would set off the strobes on pre-flash. Having worked with lights in ETTL mode exclusively (2-3 Speedlites) I found having to re-learn basic lighting again. I did NOT use a meter as I wanted the trial and error experience to learn from.

The only way I could control the exposure was by changing f-stop. Shutter speed, in camera under- or overexposure did not seem to have any effect. Is this normal in a studio setup? Only having f-stop, stobe power setting and positioning of the strobes to control exposure? Also my max shutter sync speed was 1/320. Anything above that and I got partly "cut" or dark pictures.

Here is three samples of what I came up with after an hour of playing around. I definitely learned that f/7 - f/16 was the way to go :)

http://www.galaxies.dk/studio/moneymaker_small.jpg


http://www.galaxies.dk/studio/coke_small.jpg

http://www.galaxies.dk/studio/fruit_small.jpg

[LBaldwin]

Not too bad for a first try.

When lighting for strobes the f stop controls exposure of the subject and the shutter speed controls the density and (sometimes color) of the background. Other than adding fill by lowering the shutterspeed the f stop is your primary control over exposure with strobes.

Les

[Phonetic]

Thanks for a very clear answer Les.

But how about the 1/320 max shutter speed issue? I'ts probably 1/300 but shouldnt one be able to use faster shutter speeds? I will be very hard to freeze motion at those low speeds.

[nwa2]

Thanks for a very clear answer Les.

But how about the 1/320 max shutter speed issue? I'ts probably 1/300 but shouldnt one be able to use faster shutter speeds? I will be very hard to freeze motion at those low speeds.

Modern cameras achieve high shutter speeds by using two shutter curtains, as one opens the other closes. With speeds over about 1/125 this results in the sensor / film being exposed as a strip which moves across the film ( like a scanner). The max flash sync speed is the max speed where the first shutter is fully open before the second starts to close.

Using a single (very short) flash above this speed will result in only the part of the sensor/film being exposed that is left with the gap between the shutters.

The 580EX and 430EX hot shoe flashes provide what they call "high speed sync", i.e. they can operate at faster shutter speeds. They do this by firing the flash several times during the exposure to maintain the exposure as the slot between the shutter moves across the sensor.

Studio flash (to my knowledge) can not do this.

Neil ..

[Phonetic]

Thanks both for swift answers. Kinda knew that they wouldnt high speed synch as a Speedlite, but somehow had imagined they would go to about 1/500 sec.

On my 30D its 1/320 and on the 5D I tried the max safe shutter speed is around 1/200.

Here's one of my friends who jumped out in front of the camera :)

http://www.galaxies.dk/studio/fun.jpg

[Jim M]

To answer your question, yes all of the things you discovered are normal with studio flash.

In the studio, you can pretty much ignore shutter speed as long as it is slow enough that the shutter curtain doesn't cut off part of the image and fast enough that ambient light isn't adding to the exposure. Normally, any shutter speed faster than 1/60 second will produce the same result. Exposure compensation does not work with the camera set to manual when using a manual flash.

The effect LBaldwin noted is not normally used in the studio, but can be used in certain situations where "dragging the shutter" will add exposure to the background from ambient light or where flash is only being used as fill.

[Macbeth]

One thing I've learned when using studio strobes is if you want or need to open up your apeture, but you can't up your shutter speed any more, you can use ND filters. Works like a charm.
Nice shots BTW.