What is ISO?
ISO, an abbreviation that stands for “International Standards Organization,” is your camera’s sensitivity to light. In film photography, ISO is referred to as “film speed.” You have probably seen these numbers on film canisters in the past: 200, 400, 800, etc. Those numbers represent different ISO settings—the lower the number, the less sensitive the film will be to light; the higher the number, the more sensitive the film will be to light.
However, because the majority of product photography these days is digital, everything in this article will relate to utilizing your digital camera.
In digital photography, the ISO setting on your camera controls the light sensitivity of your camera’s image sensor. Typically, photographers use ISO settings between 100-1600, though on newer, higher-quality digital cameras, settings go as low as ISO 50 and as high as the 200,000s. Again, the principles are the same as with film photography—the lower the ISO number, the less light your camera will be able to gather; the higher the ISO number, the more light your camera will be able to gather.
If you’re shooting in manual mode (M), you’ll need to control ISO yourself, but if you’re shooting in priority mode (P), ISO will fluctuate low to high automatically, depending on your priority mode settings, subject, available light, light source, and desired aesthetics. You can learn more about your camera’s manual settings reading our post How to take advantage of your camera settings.
Whether you’re shooting in manual or priority mode, when the ISO is changed, the shutter speed and/or F-stop will also need to change for a proper exposure. When you adjust to a higher ISO, you will need half of the previous amount of needed light to get the same exposure.
Example: You’re shooting in priority mode for F-stop because you want full control over depth of field. Your original setting is 1/250 F8 @ 200 ISO. If you changed the ISO to 400, you would need to change your shutter speed to 1/500 so that F-stop could remain at F8. Likewise, if you changed the ISO to 800, you should change shutter speed to 1/1000. If shutter speed did not change along with ISO, the images would not be properly exposed, as shown below.
There are two major factors to consider when deciding whether to change your camera’s ISO setting for product photos:
- How much light is available in the area where you’re shooting and
- Whether or not you have image stabilization equipment such as a tripod.
1. Available Light
Available light is how much light is available in the area you’ve selected for photos. If you’re shooting pictures outdoors, in a well-lit studio, or in a room with large windows, you’ll probably have plenty of available light to work with, so your camera doesn’t really need extra help gathering light and can remain between ISO 100 and 400. However, if you are taking photos in a dim environment, your camera is going to need that extra light sensitivity provided by a higher ISO setting above 400 to gather enough light for a proper exposure.
Note: Using your camera’s built-in flash or an external flash is one means to gain extra available light and keep the ISO setting low. However, natural sunlight or softbox studio lighting is always best, so use those light sources when you can.
2. Image Stabilization
Product photographers usually don’t have to worry about their subjects moving around as they try to get a clear shot. However, tripods or other types of image stabilization concessions, such as bracing the camera on a desk or some other hard surface, should be made to minimize “camera shake,” especially during lower-light and lower-ISO situations.
Note: Camera shake still occurs even when cameras are secured on a tripod but someone presses the shutter button manually. To minimize camera shake, we recommend purchasing a sturdy tripod and using either a shutter release cable or remote, or using the camera’s self-timer mode.
Available light and image stabilization are two very important factors to consider, primarily because the best product photos are captured at the lowest possible ISO. This is because increasing ISO produces “noise.”
Using a higher ISO setting means losing image quality by creating “noise” and other effects like chromic aberration (discoloring). “Noise” is the pixelation in the image that makes it look distorted, discolored, and “grainy.” All images are made up of pixels, so some noise is to be expected, but overly-pixelated images lose a great deal of sharpness and clarity. Pixelation makes for blotchy skin tones and “blocks” of color where the viewer should see detail, among other things.
Based on these example images, it’s clear that shooting at lower ISOs (max 200) will keep your product photos free from excess noise and shorten the time you spend editing. Noise is also fairly difficult to fix, even with the best post-processing software. It is not impossible, but spending hours correcting for noise can severely hinder your workflow efficiency.
The qualities of a low ISO are: a wide range of color with good saturation, crisp image clarity, and good contrast. At lower ISOs, your camera is able to capture more information in the image, thus capturing the likeness of your product as close to its true appearance as possible.
Using an ISO of 100-125 will mean that you need a strong and even light source. Keep in mind that you will want an F-stop between F11 and F16 for a deeper depth of field and better focus. An ideal setting for a properly exposed image of a stationary product in continuous studio lighting is ISO 200 with a shutter speed of 1/125 at F16
You can use an external flash, but keep in mind that you will only be able to adjust your settings to 1/250 due to the restrictions of the sync communication with your camera. Anything over 1/250 will create a “sensor line” over your image. We suggest using studio-type continuous light, but if you choose to go this route, you will have to remain conscious of getting too high in the ISO settings and losing quality.
Continuing your education in camera basics and your specific camera brand and lenses, practicing to find your balance and becoming efficient in processes will optimize your time and your imagery.