Shooting with flash at high shutter-speed ?

[JPS]

Hi !

I just bought a set of OLD studio-flashes (Elinchrom 11 and 22), wich doesn't offer the possibility to reduce the amount of light...

I tried them at my place, but as the space is rather restricted, i can't move the flashes away enough, so i have to use 1:250 at minimum f/11, even at ISO 100 !

I would like to be aboe to use f/4 to blurr the background, bu then i would have to reduce the shutter-speed acordingly... I remember having read that there's a way to set the D200 to be able to shoot with flash at very fast shutter-speed, but i just can't remember HOW !

Any idea?

TIA,
J-P.

[KeithM]

No direct experience with this J-P, but the manual refers to Auto FP High-Speed Sync, custom menu option e1 - but this only applies when using Nikon Speedlights ( SB-800, SB-600 and SB-R200 ).

Looks like an ND filter ( on the lens or ND film over the flashes ) would be the answer ?

K.

[BARBARA LUKE]

JP.. how about putting 1 or 2 layers of white meterial over the light just to tone it down....i done that a few years ago with a strong studio light that i couldn't reduced the amount of light ...an cos i didn't have any backdrops at the time i managed to blur the backgroung out....try it it just might work for you as well....saved me a lot of time in PS....Barbara

[GaryB]

No direct experience with this J-P, but the manual refers to Auto FP High-Speed Sync, custom menu option e1 - but this only applies when using Nikon Speedlights ( SB-800, SB-600 and SB-R200 ).

Looks like an ND filter ( on the lens or ND film over the flashes ) would be the answer ?

K.

I am pretty sure in this mode the flash has to fire several times (and so has to be high speed capable)

[JHT]

"I would like to be able to use f/4 to blurr the background, but then i would have to reduce the shutter-speed acordingly"
Actually the shutter speed shouldn't affect your exposure. Flash duration is usually shorter than your shutter speed. In this case the flash is determining the duration of your exposure. Any shutter speed faster than your max sync speed and your focal plane shutter will only expose a partial frame. The exception is when using the high speed sync feature: as mentioned above, I believe it pulses several times with a dedicated Nikon speedlight.

[Tom V]

I am pretty sure in this mode the flash has to fire several times (and so has to be high speed capable)

Right. Nikon Speedlights' FP High-Speed Flash feature basically fires repeatedly / continuously while the slit between the shutter curtains travels across the focal plane. It lowers the power of the flash and stretches out the flash duration. The downside is that the level of illumination is low, so the distance from flash to subject cannot be too much (less than 15 feet?).

When your shutter is set for, say, 1/1000th of a second, the shutter curtains are not traveling across the focal plane in 1/1000th of a second. Instead, they are going as fast as they mechanically can, and 1/1000th of a second after the first curtain starts opening, the second shutter curtain starts to close. The second curtain might be following just 4mm behind the first. A flash exposure at this shutter speed will result in a 4mm wide sliver of exposure on the sensor.

Normally, a small flash like a built-in or shoe mount, has a illumination duration of 1/1000th of a second or shorter. A typical "studio" flash like Speedotron, Norman, Boncolor, etc. has a flash duration as slow as 1/300th of a second. The large flash tubes take a lot of power to "flash" and the "flame" does not go out right away. The larger the flash tube, the longer the flash duration.

Basically, there is no way to adjust flash exposure using shutter speed. Well, maybe with a leaf shutter, at high shutter speeds, but it would be iffy, and not give you much range, if any at all.

When I use my Speedotron flash system, I have to "dial" down the whole pack's available energy to about 1/4 or 1/8 power, and then only use half the available power. I use softboxes with internal baffles, shoot at ISO 100, and at f/11 or f/16. Ugh. I have a total of 4,800 ws available, but usually only use 100 to 400ws for 90% of my work. All this (that) power is (was) good for shooting with large format view cameras, slow film, slow lenses, and preferred apertures around f/22. I shot motorcycles the other day, using my DSLR Fuji S5, plus 5 flash heads. I had the power packs turned down to half power, and was still shooting at f/13. My Nikkor 85mm PC lens stops down to f/45, so this aperture is not extreme for this lens.

The new Nikon D300 and D3 only have normal ISOs down to 200. :crazy: I won't consider buying them, because I don't want to shoot in the studio at f/22.

Sometimes, when faced with too much light, I bounce light off the wall, or use an additional flash head to bleed power, or aim a light away from the set (even into another room). Thick diffusers will knock the light down and create a softer light. You can paint the inside of the studio a darker color, to help absorb ambient light and wild light from the flashes that is bound to get loose.

I painted the ceiling in my basement studio flat black, the walls are dull beige, and the floor is gray. It makes it possible to shoot low key images, even with somewhat excess light. This shot has one large softbox to the left, a soft box in the back right bouncing off the wall, and a black piece of FoamCore (cardboard) a few inches to the immediate right to soak up light (actually it was in the shot, and I retouched it out).

[JHT]

Well put, Tom.

[rekhon]

Exceptional shot Tom! :bowdown: :bowdown: :bowdown:

[GaryB]

Grat info Tom and a stunning image!