Comparison: 18% Grey card with white balance grey card

18% gray cards (grey cards) are used to measure exposure and digital photography white balance gray cards are for custom white balance. They are not interchangeable.

http://www.imagemaven.com/white-balance-card-comparison/

Many people do not understand the difference between the two types of gray cards. This video shows and explains how to use the cards and gives some examples of situations where you would use them.

You can use the 18% gray card to measure the exposure of a scene. Point your camera at the card, fill the frame with the gray card and take a meter reading. Use that meter reading for your next pictures and they will be perfectly exposed. This is great for shooting snow scenes and doing copy work.

A digital gray card is used for white balance. You use it to get custom white balance in a scene. Cameras don't know what the colour temperature is in your scene. They base automatic white balance on an average of all the colours in your scene, not on the colour of the light falling on it.

Detailed instructions on how to use a WB digital gray card::
http://www.imagemaven.com/how-to-achieve-neutral-white-balance/

If you take a reference photo with the white balance card in the shot, then you can use that to set a custom white balance in image editing, or you can use the card to generate a custom white balance in-camera.

To use it in editing, take a reference photo with the card in it. Doesn't have to be full screen. If taking a portrait, get your model to hold the card near their face. It should be exposed normally. Then in Photoshop or your favourite image editing software, sample the gray card with the neutral colour picker to set your custom white balance, or gray point. You can use curves, or you can use the camera raw white balance tool for this. Once you get this value (white balance correction) then you can apply this setting to all your other photos taken under this colour temperature of light.

All image editing software has this "neutral picker" feature. So with ONE click you will have perfect neutral white balance. That's a great starting point.

If you like you can modify the white balance from that point on, but most of the time I just leave it where it is, unless I want to warm up or cool down my shots.

If you have any questions, just leave a comment with this and I'll answer it here.

Category:

Howto & Style

Tags:

• Grey card
• gray card
• 18% gray
• kodak
• white balance

[Edgargraphics1]

Thank you for this info, really helped!

[MarleneHielema]

@Edgargraphics1 Glad to hear it. Thanks for your comment!

[xsjad0man]

hello with the grey card do you take a picture filling the hole frame of the photo like you do with the white cards?

[MarleneHielema]

@xsjad0man No, you just need it in the same light as your subject. So if a studio portrait, I face the card towards the main light and if a landscape, I hold it at arms length myself and take a shot. I have examples in the blog post cited in the video description.

[khashy87]

from which of the automatic white balance should you take the costume white balance from a gray card?

[MarleneHielema]

@khashy87 You can use the grey WhiteBalance card (if it's big enough). I don't typically use it that way though, I sample the WB card after the photo has been taken. I find the WB grey cards more accurate than using a white card for custom WB. Have a look at my related blog post in the video description.

[MarleneHielema]

@pinkdoorsfloyd Thanks for the comment! Glad you found it helpful.

[pinkdoorsfloyd]

Thanks for the upload! Very helpful!

[hyperfocus2011]

The grey card also sets white balance

[MarleneHielema]

@calizormc Yes, On location. Take a photo of the WB card at the same time you're shooting the rest of your pictures. Use it as a reference later when you get home and start editing your photos. Works best with RAW files. If you shoot only jpgs, then you might want to use an ExpoDisc or set up "in-camera" custom WB. That just takes a lot more time that shooting the card.