With the right equipment, photographing paintings, lithographs, or other fine-art is fairly straightforward—or is it? Here's a look at how to use studio lights and a tripod to make a successful reproduction.
I was recently called upon to photograph a lithograph by Marc Chagall, “King David, 1958.” Adorned with a beautiful gold frame and behind non-reflective glass, the painting posed several challenges. Here's a brief overview of the wrong and right way to photograph flat art.
First, the wrong way
In this first shot, I did everything wrong. I set my Canon 7D (with a Sigma 17-50mm f/2.8 zoom lens) to ISO 800, auto exposure, and auto white balance and shot handheld at 1/20 sec at f/2.8 under fluorescent light, then shot a JPEG. The color cast is inaccurate, the lighting is not even, and if you enlarged the image enough you'll find some graininess (not too bad; after all, it is the 7D) and evidence of overall image blur due to camera movement. Also note that the artwork is at a slight angle and that there is some keystoning because I did not have the camera properly positioned yet.
Let's fix this disaster!
Tripod and level
The first rule of art photography is: Use a tripod. After swapping my zoom lens for a 50mm f/2.5 Canon Macro lens, I set up my camera on a Flashpoint F-1328 Carbon Fiber Tripod and F-3 Ballhead. Then I used a level first to make sure the painting was level. Then I used the 7D's level tool to make sure it was level. I positioned the camera so the sensor plane was parallel to the artwork, with the camera positioned about 5 feet away, placed so it was aiming at the center of the artwork.
The lighting's still wrong here, but now the there's no distortion. (Yes, there's about a 0.5 degree tilt left, because I accidentally moved the camera a fraction before tightening the ballhead. I'll fine-tune that in before I take the final shot. Always double-check your levels!)
Getting the lighting wrong
Then, I made a mistake, deliberately, for the purpose of this article. I popped up the flash, and took a picture.
I did this deliberately because this is actually how many people photograph flat art, and I wanted to illustrate why they'll always be disappointed with the results: If the light source is too close to the lens, light will bounce right off the subject and back into the camera, causing a reflection. A camera's pop-up or built-in flash is almost always the culprit. This is the same phenomenon that causes reflections in eyeglasses, red-eye, and all sorts of other problems. It's called the Angle of Incidence, and you want the angle of your light source to be as far from the camera as possible.
Here's a diagram of the light placement in the above photo:
As you can see, the angle of incidence in this case is 0 degrees. That will always produce a reflection that will ruin your photos. Always!
Getting the lighting right
Now, let's fix the lighting. To get a good, evenly-lit reproduction, you need at least two lights, each at a 45-degree angle to the artwork, set at equal light output settings. This way, the light bounces off the surface and harmlessly away from the camera, while still illuminating the artwork.
I set up two Flashpoint 1220 monolights on either side of my camera, at 45 degree angles pointing towards the center of the artwork, set at ¼ power. Here's a diagram of what the set-up looked like:
In addition to the lighting and tripods, I wanted the highest-quality image I could get, so I dialed down the ISO to 100, switched to RAW, and changed the White Balance to Strobe. Using a Gossen Digiflash light meter, I checked to make sure the light was falling evenly on the entire surface of the painting. To do this, I took five readings: Center, and then at each corner. Fortunately, since the painting only measures approximately 12x16 inches, two lights with 6-inch reflectors were sufficient for even lighting.
If this were a larger painting, a four-light set-up might be necessary, with the lights arrayed with two on each side, each light at a different height. Big artwork is trickier because there's a larger surface to light evenly, and is beyond the scope of this article.
The result: I cropped out the frame to show this evenly-lit, high-resolution, perfectly-exposed and color-balanced, glare-free photo of a classic piece of art history.
What about the frame?
Lighting a frame can be tricker than lighting the painting itself! Note that in this uncropped version the frame suffers from a pair of hot spots. This is because the light source is too small. Light boxes or umbrellas would spread out the light, reducing or eliminating the hot spots. You would need a light box that is a bit larger than the artwork and its frame, in order to cover the entire thing. However, the larger light source could also introduce some glare to such highly reflective artwork, so you will also need a polarizing filter to remove these reflections.
What if you're photographing art in a museum?
Obviously, the above advice applies only in situations where you can completely control the light—something you can't do when visiting and photographing artwork in a gallery or museum. In a museum, you have no control over the light and certainly can't use a flash. Turn it off, and get the best shot you can—if museum policy allows you to take pictures at all. Want a perfect reproduction of museum art? That's what the gift shop is for!