BI-WEEKLY LIGHTING THEME: Graduated Specular Highlights

Earlier this week there was a thread, here in the Lighting Forum,

about creating a graduated specular highlight. The sample photo in

that discussion was an ad for Schneider Lenses and featured a close-

up of the front element of a large format lens with a beautiful

graduated specular highlight on the glass surface of the lens. The

question was about how that graduated specular highlight was created.

 

For those of you who have been following these Lighting Themes, you

might remember that a specular highlight is a reflection of a light

source. And that a larger, closer diffused light source creates a

larger, smoother and more transparent specular highlight. (Previous

Lighting Themes are archived in the Administration section of this

Lighting Forum if you want to check them out)

 

It makes sense then that a graduated diffused specular highlight is a

reflection of a graduated, diffused light source. A softbox has an

evenly lit front surface so is not as easily used to create a

graduated diffused specular. A scrim can be partially lit so that

the light intensity falls off from the center out to the edges and is

ideal for creating graduated specular highlights.

 

In recreating this effect in the studio I used a very large 6.5 ft x

6.5ft scrim and found that even with such a large scrim I had to

position it within 2-3 ft. from the subject lens because the surface

of the lens was convex and reflected light from all directions.

Having the scrim positioned so closely to the lens surface would make

it very difficult to use a reflector card instead of a scrim and

still have room to bounce the light into the card. So I'm thinking

that a sxcrim, rather than a reflector card was used in the sample

photo from the original post. I could be wrong, I usually am, but I'm

sticking to a scrim for this effect.

 

You can use any type of light and any modifier on that light to light

the scrim which will be reflected in the surfqace of the subject. You

can light the scrim with a large diffused source or a small projected

source, a softbox, bare reflector, or grid spot to project any shape

and edge softness of the light onto the scrim which will then reflect

as a graduated specular highlight in the subject.

 

For example, this first shot uses a soft box without a scrim and you

can see that the specular highlight is extremely gradual across the

surface of the lens.<div></div>

This second sample has a medium softbox behind the scrim and the specular gradient is slightly more abrupt<div></div>

This third version uses an 11 inch reflector behind but very close to the scrim's surface for a stronger highlight<div></div>

In this fourth shot the same 11 inch reflector is now fitted with a 20 degree grid but is placed farther from the scrim for a slightly softer transparent specular highlight<div></div>

Finally, a word about scrims. You can buy commercially made scrims such as those made by Calumet, Scrim Jim, Matthews and Lasolite. I've used a 6.6 ft square scrim from Lastolite. It's a large scrim with a metal shock-corded frame, velcro around the perimter for a smooth tight fabric and it works very well in the studio or on location.

 

But you can make your own scrims from wood or pvc frames and rip-stop nylon, sail cloth, frosted acetate, translum, vellum, bed sheets etc. For this theme you will want to be able to stretch the fabric smoothly over the frames so that there are no wrinkles to show in your highlights. I've even used white seemless paper as a scrim when I needed a really large scrim and had enough strobe power to blast through the paper.

 

Occasionally people are interested in seeing the equipment and setup used to light these themes and this time I think it would be interesting to see the effect of various lighting on the scrim itself.

The scrim is suspended overhead and slightly behind by two light stands, one on each side. The light source is strobe.

 

Here are some setups. The first series uses just an 11 inch reflector behind the scrim at a close and then more distant position. The round reflector gives a round shape to the light.<div></div>

Adding a 20 degree grid to the 11 inch reflector makes a more defined, tighter circle of light on the scrim<div></div>

Sometimes you want a rectangular shape to the light on the scrim. Different sizes of soft boxes work well for that<div></div>

Here an optical spot makes a very sharp circle of light when placed immediately behind the scrim or an arc of light whan placed at an angle to the scrim.<div></div>

Finally, a bare bulb strobe head behind the scrim for a more random circular pattern of light.

 

You can try this graduated specular highlight effect yourself. Make or buy a scrim and try different positions and modifiers on your light source. There's an infinite number of light effects, sizes and shapes that you can create. Give it a try and have some fun!<div></div>

Thanks Brooks!

 

The equipment setup shots are particularly nice for those of us that havn't put in the time to know this by rote yet.

 

Thanks for a nice summary of technique.

Again, thanks - that's very useful.

Thanks Brooks!

 

This is great job!!!

 

Could you please tell, what kind of material you use for that scrim plane? Thanks ones again!

Eugene,

 

The scrim I used is a commercially made scrim from Lastolite. It comes with one 1.25 stop diffusion silk and one two-sided reflector fabric, white and gold.

 

The diffusion fabric is very thin and feels like silk but I'm sure it's a synthetic version of silk.

as I mentioned in the last thread, you can get this material (basically sailcloth) from Calumet photo rather cheaply.

Brooks,

 

Thanks for the awsome theme. I'm gonna give this one a shot sometime this week; I just love playing with specular hilights, and thanks to your theme I've got a few ideas rattling around in the ol' noggin.

 

Here's hoping I get something successful enough to upload ;-)

 

Jordan R. Urie

Brooks,

Great theme. And the images really help a lot. This is one of the better ones (in my opinion). And VERY nice set up in your studio by the way.

Thanks everybody. I was a little concerned that the focus of this theme was a bit too narrow and technical, and it may be, but this technique is not hard as you can see.

 

Shawn, thanks for your comments about my studio stuff. The studio is a mess right now but the one piece of equipment which really makes life easier in the studio is the ceiling rail light system. Cost was not much more than a good remote boom and several light stands but it really makes things easier for most setups.

 

The resolution on these shots is really low but did you notice the yellow smiley face sticker on the powerpacks in the cart? They're frownie faces with a red bullet hole in the forehead and some dripping blood. Very attractive and quite the conversation starter on a shoot! #8^)

 

I hope you guys try some shots with this technique and post them here for us to see.

Brooks,

 

Like everyone else who's commented so far, I think this theme is excellent.

 

Personally I don't think it's too technical, the techniques are simple enough and don't need specialised equipment, so it's within the reach of everyone who wants to improve their skills.

 

And, like every studio shot I've ever done, the approach is to first decide on the required effect, secondly to get the camera position right and finally to arrange the lighting to get that effect.

 

It seems to me that people are a bit shy sometimes about posting their own examples but this is not a critque forum, nobody is going to make any nasty comments and nobody expects to see perfect results from experimental shots. We all learn from seeing other people's work, so don't be shy!

 

BTW, you must send me a detail shot of your blood soaked victims - do they have names? Creative Director 1, Creative Director 2 etc?

Great theme Brooks. Somehow I knew you were going to do this. lol

 

I am shy because I know I didn't get what I was after but here goes anyway...what the hay.

 

For a scrim I used a big white plastic shower curtain pinned on my background stand. I tried several lighting methods and ended up with a 7" reflector with barndoors. The light was about 4' behind the curtain and angled slightly across it. The barndoors helped to control the spill to some degree. I tried to create the graduation on the scrim then reflect that into the lens, at least that was my plan. This first picture is a crop using only the scrim. I think the purple color is from the lens coating because I was getting that no matter what lighting I tried???<div></div>

I then added a 32x40 softbox on the opposite side for fill and a 7" reflector fitted with a 20 degree grid spot for a background light. Adding these 2 lights presented their own fair share of additional problems and I tried to deal with them best I could but I was only partially successful.<div></div>

Here is the setup. I'm sorry I overexposed the scrim by probably 4 stops but I wasn't thinking. I just backed up and took these then tore everything down. It doesn't show the graduation I had across the scrim. Again, I'm sorry.

 

 

RDee<div></div>

I forgot to mention I had to put a black card and some black material as a curtain between the scrim and my background to try and cut the spill from it. That is why the light stand is positioned there. That stuff was propped again that stand and the scrim stand.

Robert,

 

You da MAN ! Those shots are excellent and exactly to the point of this theme. Good job! Another thing to notice about your shots is how nice the lighting is on the rest of the camera from using these large diffused sources. I've seen real paying commercial jobs (even some that I've done) that didn't look as good as these shots.

 

I think you'll agree that this technique isn't that difficult and the results are worth the effort.

Thanks Brooks for the kind words. I am really sorry I did not get a good shot of my scrim because I had a fairly nice transition across it. By that time I was stressed out and not thinking.

 

Thanks again for the Lighting Themes.

RDee

ANOTHER great theme. Thanks Brooks!

 

I have an off the wall idea of using the techniques in this theme. Let's hope it's not an experiment gone bad!

 

Unfortutately, (or fortunately) we recieved 5ft of snow in the last week. So I'll be hitting the slopes this weekend.

 

Mike