Expo Disc White Balance Tools

In advance of a seminar I am participating in, the good folks at Expo Imaging recently supplied me with a set of their Expo Disk white balance tools. I received both an Expo Disk Neutral, and an Expo Disk Portrait.

Expo Disk custom white balance tools have been around for a while, and I admittedly have been reluctant to try them. Don’t get me wrong; I am a big advocate of custom white balancing my digital camera. The less time I spend color-correcting files the better.

Here’s the deal though, I have always used a gray card to measure the color of the light falling on my subject. You know the drill—place a gray card at the subject position and follow your camera’s directions for setting a custom white balance. You are in effect measuring the light temperature reflecting off the gray card.

The Expo Disk goes at it from the opposite direction. Instead of measuring reflected light, an Expo Disk measures the light falling on your subject similar to the way an incident meter works. You cover your lens with the disk and point the camera at the light source instead of at your subject.

As an example, if I were taking a portrait outdoors I would normally have my subject hold a gray card in front of his or her nose so I could take a picture of it to set a custom white balance. I would have to repeat this procedure each time we changed locations.

With the Expo Disk I simply place the disk in front of my lens and photograph the light source (in this case the open sky) to set a custom white balance. I can do this quickly and easily without involving my subject or a gray card. (You can watch video demonstrations of the Expo Disk in use here.)

It doesn’t take long to figure out the Expo Disk is much more convenient to use. But how accurate is it compared to my trusty old gray card?

Take a look at the test images. In the first series I photographed a gray / white / black target outdoors in open shade. I set my Canon dSLR at 100 ISO in aperture priority at f/5.6. As you can see the camera’s Daylight white balanced recorded a blue color cast as would be expected. Auto White Balance did a better job, but still far from neutral.

My trusty gray card is close, but still a tad bit warm. The Expo Disk Neutral did exactly what it should and rendered the image without a color cast. I balanced the last image using the Expo Disk Portrait that slightly warms the color balance for better skin tones. Again, it performed as advertised.

For the second series of images I taped a gray card under a tungsten light fixture. As you can see the camera’s Auto and Tungsten white balance settings are not even close, while the Expo Disk balanced shot did a great job neutralizing the tungsten color cast.

My final verdict… I will be using the Expo Disks a lot from here on out. In practice they make taking white balance readings quick and easy. (Not to mention they look really cool hanging around your neck from the supplied strap.)

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4 Responses to “Expo Disc White Balance Tools”

  1. http://tinyurl.com/openson39031 Says:

    “Expo Disc White Balance Tools RG’s Digital Photography Tips” was indeed a extremely pleasant posting, . Continue writing and I will keep reading through! Thank you -Tabitha

  2. http://tinyurl.com/yahowatte59218 Says:

    Your blog post, “Expo Disc White Balance Tools | RG’s Digital Photography Tips” ultrastudios.org was indeed truly worth writing a comment here! Merely wanted to point out u really did a tremendous job. Many thanks -Rachael

  3. frankedgar77 Says:

    Thanks for posting this, I am always looking to get the best shade for my pictures and this post will help me a lot!

  4. breathtaking images Says:

    Thanks for this awesome post, I have been looking for something like this that will help me with my photo balances, much appreciated!

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