The Big Light

Dave Montizambert joins in our feature on high-end gear

Receiving an assignment to light and photograph a gigantic, shiny object such as this 80-foot, orange, semi-trailer truck would put the fear of God into most us, but it need not if you employ the correct principles of lighting to the challenge.

This image, for Allied Movers/Quality Move Management, was to appear in brochures and on billboards. The creative brief for the image was up to me since no advertising agency or graphic designers were involved – it was a client-direct job. The only direction they gave me was ‘Give us a dramatic image of one of our trucks set against a cityscape of Vancouver, BC.’ There were certain logistical problems to overcome, the main being that a semi-trailer truck cannot just be shot anywhere. Finding an area with downtown Vancouver as the backdrop did not work out; since the subject was so large, the best areas to shoot for the cityscape were impossible to get shooting permits for. The solution was pretty obvious, shoot both the truck (see image 01) and the city (see image 02) separately at optimum locations, then composite in Photoshop.

Now getting back to the fear of God thing – when it comes to lighting 18-wheelers, size is everything. A three-foot by four-foot soft-box light source placed in close to the subject is a large source of illumination for a head and shoulders studio portrait, but not for a truck. Size of source is relative; if we want to have a pleasing 'soft wrap-around' light quality on the truck then we need a source of illumination that is larger than it. Since the shot was to be set in an outdoor environment and not in studio, this made the whole job simpler and less expensive. Let me explain. If shot indoors a huge flat or jumbo soft-box larger than the truck would have to be constructed and then suspended above the vehicle. In addition, an indoor space large enough to accommodate such a large subject would have to be sourced and rented for a couple of days. None of this would be necessary since the shot was to be in an outdoor environment; I just had to find a large wide-open area that the city officials would let me shoot in, then pick my time of day and weather to create a massive light-source from the sky (see image 03). Wide-open space was essential so that there would be no buildings, trees, or telephone poles obstructing the sky from the truck.

To have a large source of illumination outdoors you need to shoot either on an overcast day or at sunset, when the sun dips towards the horizon. The added benefit of shooting on a sunny day around sunset is you get two lighting scenarios for the price of one:

1. When the sun is really low in the horizon you get a beautiful balance between the sun and the open sky.

2. Once the sun sets you get lighting from open sky creating a beautiful soft light sheen on objects such as our shiny truck.

In the first of these two scenarios, the sun creates hard light while the open sky creates soft light. When the sun is so low on the horizon, the light rays have to travel through so much atmosphere that the direct sunlight is diminished in brightness to the point that it cannot overpower the open sky lighting as it does from late morning to late afternoon. This would be the equivalent of lighting a subject in the studio with two light sources – a relatively large soft-box and a relatively small light source such as a bare strobe head (powered down to match the soft-box intensity) – at the same time. This kind of lighting creates lots of sparkles (small intense specular highlights) from the direct sunlight, as well as a beautiful sheen (large-sized, low-intensity specular highlights) from the open sky over the surface of a shiny object such as our truck. The cool thing is you can catch both scenarios if you set up in advance of sunset – shoot some images while the sun is just above the horizon, and then again once it dips below the horizon.

At the time of scouting the location, four days before the shoot date, the sun was setting at the perfect point. However, four days later, mixing setting sun with open sky was not possible; the sun was setting four minutes earlier and so did not travel around as far west which gave some rather large hills an opportunity to obscure the sun from the truck before the official sunset. Not to worry, the open sky lighting was all I really needed; the other would have been a nice variation.

The other consideration with this lighting scenario is colour or white balance. Many photographers with digital SLRs set their white balance (WB) to Auto or better still do a custom WB off a neutral tone or from an Expodisc. Using any one of these solutions would normally be fine, however, in this image I wanted to preserve the flavour of warm 'magic hour' light and using either Auto WB or a custom WB neutralis es the golden colour balance of a sunset. To solve this minor problem I set WB to daylight; this captured a beautiful warm light, giving the open sky lighting a warm glow on the truck.

The colour balance of the light changes rapidly towards warm as the sun dips lower in the sky; every few minutes the warmth increases significantly. If you feel that the warmth is too much you can easily notch it back during processing of the files in applications such as Adobe Camera Raw or Adobe Lightroom. If you find changing the colour balance and tint sliders a little challenging, consider making two versions of the image, one with full warmth 'as captured' and one in which you neutralised the image in Adobe Camera Raw or Adobe Lightroom on a neutral colour in the image, by clicking on it with the WB selector tool. With both image variations open in Adobe Photoshop, hold down the shift key on your keyboard as you click and drag the background layer of the neutralised image into the open window of the warm image. Turn down the layer opacity (the slider at the top right corner of the layer’s palette) of the neutralised image until just enough warmth shows through. This method will ensure that you keep the exact balance between Colour Balance and Tint as you lessen the warmth.

The final consideration for the capture of this image was exposure. An incident meter was positioned with its back to the truck and the front facing the open sky, above the camera. As the sun dropped lower and lower, which happened very rapidly, so did the exposure. But, because the sky is so far away from the truck, it of course made no difference whether I walked the 160 feet from the camera to the truck to take my readings or whether I took the readings beside the camera – the further away the light-source, the more light depth of field there is. Which means, if the light source is far enough away – and the open sky was – then no measurable brightness difference will occur between two points even though one might be closer to the light source than the other. This made my job easier; I was able to take incident meter readings (about one every minute or so) and adjust shutter speed without having to step away from the camera.

Once the image was opened into Photoshop on my workstation back at the studio, I selected and deleted the background behind the truck and trees, then pasted in one of my stock images of the Vancouver Skyline (see image 04). To make the truck really jump out of the image and to create a surreal feeling I selected the truck, inverted that selection, created a Hue and Saturation Adjustment layer (see image 05), clicked on the Colorize option, and then dragged the Hue slider to 241 and Saturation to15. This gave everything but the truck a steel blue tint and completed the image (see image 06).

As you can see, having to light and photograph a large shiny object like this 80 foot semi need not send you to your knees as long as you can shoot outdoors with unhindered open sky using these few simple principles from above.

Timing: Late September (Sept 22) around sunset
Camera Distance: 160 feet
Camera: Hasselblad ELM with Sinar 54H digital back
Lens: Hasselblad/Zeiss 150mm
Exposure: f11 from 1/8th to 2 seconds, single shot mode

CAMERA TECHNICAL DETAILS

The Sinar 54H digital back is a 22MP (sensor size – 49mm x 36.7mm) digital capture – 5440 x 4080 pixels, creating a 130mb 16-bit file. It can also be shot in 4 or 16 shot mode. Sixteen shot mode creates a 510mb, 16-bit file. I shot in single shot mode since you need vibration-free shutters for 4 or 16 shot mode ; the Hasselblad shutter shakes too much. Literature claims more than 11 stops of dynamic range for this 14-bit capture. ISO range is currently at 50 to 200. I shot at 100 ISO.

visit: www.sinarcameras.com

Photo Quote: ...words and pictures can work together to communicate more powerfully than either alone.- William Albert Allard