ExpoDisc v3 Professional White Balance Filter Instructions

ExpoDisc v3 Multi-Language Instructions

ExpoDisc v3 English Instructions (PDF)

Attach the ExpoDisc

The ExpoDisc Pro v3 Professional White Balance filter can be attached to your lens using the bayonet mount step ring.  Or, you can simply hold it flat against lenses up to 82mm.

ExpoDisc - Setting White Balance

1. Cover the Lens.  Attach the ExpoDisc v3 Professional White Balance Filter to the front of your lens using the bayonet mount step ring, or you can simply hold it flat against lenses up to 82mm.

2. Manual Focus.  If you cannot trigger the shutter with ExpoDisc covering the lens, then briefly set your lens to manual focus.  Or use the camera’s “back button focus” to bypass autofocus while capturing the WB reference image (refer to your camera manual to setup this function).

3. Set Camera Exposure.  Use Aperture Priority mode in ambient light to set a good exposure through the ExpoDisc.  If using Manual mode then set the exposure before setting your WB.

4. Aim the Camera.  Under most lighting conditions, from your subject’s position aim the camera towards your light source (as if you were using the camera like an incident light meter).  The color of light illuminating your subject must pass through the ExpoDisc to get an accurate white balance.

5. Set White Balance.  From this position, set a custom WB (following your camera’s instructions).  When capturing a WB reference image, note that the image may not look gray.

6. Finished.  Return the lens to autofocus, if necessary.  Remove the ExpoDisc to photograph your subject.

ExpoDisc - White Balance Tips

Measure the Incident Light.  Understanding the ExpoDisc is an incident light metering tool will help you to use it properly. To meter incident light you should stand at the subject’s position and point the camera towards the light source. If you cannot stand at your subject’s position, then place yourself in the same light as your subject.

Ambient Light.  Point your camera towards the light source.  *If your subject is also illuminated by reflected light (green grass, painted wall, etc.), then point the camera towards your shooting position.

LED Constant Light.  Point your camera towards the light source.

Studio Strobes and Off-Camera Flash.  Stand at the subject’s position and point the camera towards the main light.

Shutter Speed when Using Flash.  Changes in shutter speed will change the ratio of ambient light to flash.  For best results photograph your subject with the same exposure (shutter speed) used to set your white balance.

On-Camera (Bounce Flash).  A ceiling or wall may change the color of your bounced flash.  When setting your WB aim your camera and flash towards the bounce surface (ceiling, wall).

On-Camera (Direct Flash).  We do not recommend setting a custom WB with the ExpoDisc when using on-camera direct flash.  The ExpoDisc is an incident metering tool and cannot be used to meter on-camera direct flash.

Metering for Exposure (optional)

When metering for exposure it is important to aim the camera from your subject position back towards your shooting position.

1. Manual Mode.  Set your camera to Manual mode.

2. Attach ExpoDisc.  Attach (or hold) the ExpoDisc in front of your camera lens.

3. Meter Incident Light.  Stand at subject position and point the camera towards your shooting position.

4. View Camera Meter.  Check the camera meter through the view finder.  Adjust the aperture, shutter speed, or ISO until the meter indicates a good “0” exposure.

5. Capture Test Image.  Capture a test image through the ExpoDisc and check the histogram to confirm the spike is centered.

6. Finished.  Remove the ExpoDisc to photograph your subject.

The ExpoDisc v3 Professional White Balance Filter has been updated with a 14% light transmission to be consistent with ANSI standards for photographic exposure meters.

Check for Sensor Dust, or Create a Dust Map (optional):

1. Cover the Lens.  Attach the ExpoDisc to the front of your lens, or hold it flat against the lens.

2. Aperture Priority f/16.  Select Aperture Priority and set your aperture to f/16.

3. Focus on Infinity.  Set your lens to manual focus and adjust the focus to infinity.

4. Aim the Camera.  Point the camera towards the brightest available light source.

5. Take a Picture.  Trigger the shutter to capture a reference image through the ExpoDisc that you can use to create a “dust map” in your image editing software.

6. Check Reference Image.  Spots appearing on the reference image indicate the presence of dust on your camera sensor.  If you intend to remove the dust spots from your images in post production, then use the reference image to create a dust map for your editing software.

Copyright © 2023 ExpoImaging Inc., ExpoDisc is a registered trademark of ExpoImaging Inc., Patent: see www.expoip.us.