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WEEKLY LIGHTING THEME: Controlling Specular Highlights............

Brooks Short - Tampa, Florida , Apr 04, 2004; 01:48 p.m.

....to define form and surface texture.

Sounds complicated but it's really not.

Specular highlights are, by definition, the reflections of light sources on the surface of an object. These reflections are often referred to as "glare". Glare is usually something photographers try to avoid because excessive glare is distracting and obscures surface detail.

Many photographers attempt to completely eliminate specular reflections by repositioning their lights or polarizing the light either at the lens and/or at the light source itself. Sometimes that's the best choice but often a shiny surface is one of the defining features of an object and should be shown.

As most people know, a diffused light source such as a scrim or softbox creates a softer light quality. The larger or closer a diffused light source is to the subject, the softer the light.

Another, perhaps less well known, quality of a large diffused light source is its ability to control the intensity, size, shape and TRANSPARENCY of specular reflections.

The props in this series of sample photographs are simply a few shiny tomatos and some glossy black rocks. The tomatos have compound curves and reflect light from many different angles while the rocks have angular surfaces and create their own set of specular highlights.

The tomatos and rocks are lit by a single overhead light. In this series I've used electronic flash and in some versions a softbox. You could also use hot lights and scrims.

All exposures are at f-32 and are digital captures at an ISO of 100.

The first photo is lit with a bare flash with a 7 inch reflector positioned overhead and slightly to the rear of the set approx. 2 ft. away. Flash power is 800ws. Notice the hard, opaque white specular highlights on the tomatos and black rocks. These specular highlights are so bright and the light is so hard that the highlights in the tomatos and rocks are pure white with no detail and the shadow areas are extremely dark with little to no detail.

Next weeks LIGHTING THEME: LIGHTING GELS will be presrnted by Garry Edwards


Single hard light with 7" reflector

Responses


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Brooks Short - Tampa, Florida , Apr 04, 2004; 01:55 p.m.

In this second shot, a 2'x3' softbox (900ws) replaces the 7" reflector light and is positioned so that the front screen is about 12" above and behind the subject. Now the specular highlights are larger and more transparent so that you can see some of the red color of the tomatos in those highlights. The specular highlights on the rocks are similarly reduced in value to a light grey and the softness of the light from the softbox helps define the form of the tomatos and rocks


2'x3' soft box replaces 7" reflector

Brooks Short - Tampa, Florida , Apr 04, 2004; 02:03 p.m.

In this third shot the 2'x 3' softbox has been replaced by a larger 3'x4' softbox (900ws) still positioned in the same location about 12" above and behind the tomatos. A fill card has also been positioned in the front of the set to brighten the front of the tomatos.

This larger softbox creates even larger specular highlights on the tomatos. These larger specular highlights are also more transparent allowing more of the red color of the tomatos to be revealed in the highlights. The light is softer than the smaller softbox and there's more detail in the shadows.


Larger 3'x4' soft box creates more transparent highlights

Brooks Short - Tampa, Florida , Apr 04, 2004; 02:14 p.m.

Finally, in this last shot a background light, 2400ws 7" grid reflector has been added. The blue/grey background is about 7 ft. behind the subject and was present in all of the preceding photos.

Because of the distance between the subject and the background, the background rendered as black.

Adding a seperate light on the background creates a second layer of detail behind the subject and creates some degree of depth in the shot.

This technique for lighting shiny objects and surfaces is a simple and effective way to control and use specular highlights to your advantage. The specular highlights in these sample photos help define the shape and textural qualities of nboth the tomatos and the rocks.

If you're interested in this level of lighting control and wanrt to learn more, this is a simple one or two light set-up that you can easily try yourself. Setup a softbox or place your light behind a scrim, find a few shiny objects to shoot and try it yourself.

The more you know, the better it gets. #8^)


Addition of a background light adds depth

ZJ . , Apr 04, 2004; 03:44 p.m.

Hi all,

I was experimenting with this still life subject and figured that it fits this week's lighting theme right on! This was lit by a portable flash through tracing paper, 45 degrees and 2.5 ft from the left, plus a white foamcore board reflector on the right.

The paper container seems to be more reflective than the bottle itself and i was having a hard time trying to reduce the hot spot on the container. Can anyone please recommend some ways to improve this picture?

Thanks in advance.


Attachment: still_life_01.jpg

Steve Levine , Apr 04, 2004; 04:47 p.m.

This is downtown Bluefield,WV.The full coal hoppers move east from the mines to the sea,empties flow back west to be refilled.This is looking east into the raising sun to capture the "angle of incidence highlights".Your theme was sort of vague this week,so I thought Id toss this in.

Garry Edwards , Apr 04, 2004; 05:22 p.m.

ZJ, I was about to make the comment in general, and to Brooks in particular, that this week's theme and his examples perfectly illustrate the need for large diffused light sources, even with very small subjects, when large, gentle and translucent highlights are required. By large light sources, I mean either a fairly large source extremely close to the subject or, when this is not possible, an extrmely large light source further away. Unfortunately many photography books and magazines fail to mention this and may also show lighting setups with the light sources far too far away.

And then you added your own example, which perfectly illustrates the problems that you've encountered by having too small a light source and having it too far away. To answer your question, Try placing a large piece of white foamcore or similar as close as possible (just out of shot) and bounce the light off of it. If the highlights on the packaging are unacceptable to you then you could spray the packaging with a dulling spray, or with hairspray or milk.

Brooks Short - Tampa, Florida , Apr 04, 2004; 06:17 p.m.

ZJ,

Garry is right. Your light/scrim is too small and too far away. See how white and opaque the highlights are on your bottle and box ?

You need a scrim or softbox 3-4 times as large as your subject and so close that it is just out of the frame.

Glass bottles present unique lighting problems because they are made of glass and extremely shiny.

I would light your setup with a large softbox overhead to define the shoulders of the bottle. Either a second softbox to the left to lay a soft, translucent highlight down the left side of the bottle or perhaps a fill card in that position to accomplish the same thing by bouncing the light from the top softbox. Another fill card on the right.

Either a cut to fit fill card behind the bottle to bounce some light through the liquid in the bottle or another light to do the same thing.

Here's a bottle shot lit with a softbox angled from overhead and the left to create the soft highlight on the left side of the bottle. It was a 3'x4' softbox, just out of the frame, maybe 12 inches away. A hard spot from the rear left to light the liquid and ice cubes and a background light.


Bottle Shot

Garry Edwards , Apr 04, 2004; 07:58 p.m.

ZJ, Brooks has given the correct answer and you will get better results, and get them more easily, if you follow his advice.

If you don't have the equipment he suggests you will still be able to improve on your present example by bearing in mind the need to have a much larger light source and bouncing the light off a white card or a piece of foamcore. This reflector will need to be very, very close and personally I would get it only just out of shot.

Your biggest single problem will be making sure that all of the light aimed at the reflector hits it in the right place and at the right angle, so that the reflected light hits your subject and none of the light from your flash hits the subject directly. The usual method is to use a large piece of black card (known as a flag)to stop light spilling into the wrong place.

Hope this helps.

Jennifer C , Apr 05, 2004; 02:35 a.m.

One of the best darned tequilas known to man! This was taken with a 800ws to camera right. I don't have a softbox, but I used my Photek Softlighter II about 8" away, perpendicular to the bottle. Then there is added diffusion between the light and bottle with a portable/collapseable (sp?) 42" disc. There is a cream colored wall camera left about four feet away and this is shot five feet or so from backdrop. One light on background with 20 degree honeycomb and red gel filter.


sitting on the white sands of cancun......

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