Depth of Field for Product Photography: The E-commerce Guide

A listing photo with a soft edge or a blurred logo costs sales. Customers zoom in, and marketplaces compare your images with everyone else's. So product photography has a stricter standard for sharpness than most genres. The instinct is to stop down hard to get it. Once you see the numbers, you see why that often does not work.

How little depth you really have

Depth of field at product distances is small. Here is the total zone in focus for a product framed across the width of a full-frame sensor, using the standard circle of confusion:

So for a 10 cm product, even f/16 gives under 1 cm. That is why only the front surface of a straight-on product is usually sharp, and anything with real depth needs help. A product photographed straight on, with its face parallel to the sensor, needs very little depth of field. At an angle, the near and far edges sit at different distances. A shoe 40 cm long photographed at 45 degrees can have 15 to 25 cm of depth, which is far more than f/16 gives.

Diffraction bites earlier at close range

The aperture you set is not quite the aperture you get. The effective f-number is the marked one times one plus the magnification. At a 10 cm frame width (magnification 0.36), f/11 behaves like f/15. At 5 cm it behaves like f/19. On a 45 MP full-frame sensor, a diffraction disc at an effective f/16 is about 5 pixels across. So f/16 and f/22 on the lens scale are an effective f/22 to f/30 at jewellery distances, and softness shows at 100 percent. The diffraction post has the pixel figures.

Focus stacking is the standard answer

Professionals shoot several frames at a moderate aperture, each focused at a different depth, and blend them. Take a shoe 40 cm wide framed on a full-frame sensor. At f/8 each frame covers about 3.6 cm, so with 30 percent overlap a 15 cm depth takes about six frames. The focus stacking post covers the method, and a rail or in-camera bracketing makes it routine. Each frame is at the lens's sharpest aperture and the final image has no diffraction penalty.

Tilt for flat surfaces

If the subject is a flat surface running away from the camera, such as a tabletop, a plate of food or a flat-lay layout seen at an angle, a tilt lens can put the plane of focus along it, so the whole surface is sharp at a wide aperture. A 90 mm lens at f/2.8 focused 0.5 m away has only about 4 mm of depth without tilt. The tilt-shift post explains how much tilt to use.

Distance does not buy depth of field

It is often said that a longer lens from further back gives more depth. At the same framing it does not. A 50 mm lens at 0.5 m and a 100 mm lens at 1 m, both at f/11, give the same 5.7 cm, because the magnification is the same. What the longer lens gives you is working distance for lights and reflectors, and less perspective distortion on the product's edges. That is a good reason to use a 100 mm macro for small items. It is not a way to gain depth.

For reference, here is roughly where the lens sits for a given product width, using the thin-lens formula, measured from about the middle of the lens:

Practical approach

Shoot flat products straight on at f/8 to f/11, where a single frame is enough. Round objects such as bottles curve away from the plane at the edges, so either accept slight softness at the wrap or stack. For anything with real depth, such as shoes, bags and watches at an angle, stack at f/8 rather than stopping down. For furniture and large pieces, step back, since the zone grows with the square of the framing width, and f/11 may do it in one frame. Small apertures also need more light, which is one reason studios use strong strobes or continuous lighting.

To check the zone for your own lens and distance, use the calculator.

Related reading: Focus Stacking: When DOF Is Not Enough, Diffraction: Why Stopping Down Too Far Hurts Sharpness, Tilt-Shift Lenses: Controlling the Plane of Focus.