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heyjoe
2nd June 2012, 08:24 PM
Hello All

I've just been given an 18% grey balance card, which has grey section,a white section and a black section. I've been reading up about what you can do with them, but I'm not sure when and how to use them- whats confusing me is when I should use it, which colour I should use (any why), and how this will help me.

I shoot in RAW, and am using CS5, I've been watching videos which have talked a lot about in camera white balancing and setting DNG profiles etc etc which has left me confused.

I was wondering if anyone could explain in laymans terms what it all means-or if anyone has a link to somewhere with easy to understand explanations please

Thanks for your help

Joe

snaarman
2nd June 2012, 09:25 PM
I have a set of those cards and I try to use them regularly, though in the heat of the moment I often forget.

OK, I think there are two things you can use these cards for.

1: You can set the exposure by making the camera meter the grey card. You would use manual exposure, hold the card in front of the camera so it fills the field of view and is illuminated by your desired light source (cloudy sky, indoor lamp etc). Now you adjust the camera f stop and shutter to get that grey card right, and your subject should now be exposed properly, providing the lighting doesn't change.

2: You can also use the white card to set the colour balance for a particular location. Some cameras have an instant white balance button or function where you hold the white card in front of the lens, take a WB "picture" and you can store that setting in the camera. If you are working with raw files, then you should notice the images come out the right colour from then on if you use the "As Shot" WB option in the raw converter.

However, there's another way: If you put the three cards in the shot somewhere and take a picture, then when you fire up CS5 and import this first raw file, use the eye dropper on the white card (wherever it is in the image) to set the colour balance. That should make the test shot the correct colours. Now for each following shot you can find the "As Previous Conversion" option hidden in a raw converter tab somewhere and the following shots should come out right as well...


Hope this long explanation is a help..

Pete