What White balance for taking white balance photo?

N

nicksnow

Well-known member
I've been using the custom white balance for a while now and usually just go AWB for the photo of the white card. then it dawned on me today: wouldn't the auto white balance be influencing the custom white balance? does this matter? if it does..is there a solution?
 
no, you do white balance by taking of photo of what you want to be white, and it changes the colors to match that.
 
No, I get that part, but to set WB on the Canon you need to take a photo of a white card and set the wb from that photo. Isn't it conceivable that whatever white balance setting is used to take the photo of the white card will effect the custom wb levels? Or is the camera smarter than that? I'm guessing yes.
 
I've never gotten solid answers on this either, but there's really nothing else you can do. I tested it once where I used auto and some other preset, and both times I'm pretty sure the manual white balance came out to the same exact thing. One tip is that for me, using a 18% grey card (the one used for exposure) as the white balance card, it both gives me completely more accurate white balances - whenever I used a white card, everything turns out green in every situation. Even I use the grey card, there is no tone but the reality of the room, which means it's perfect!
 
The information is stored in the data for the picture, I assume it can do the simple math and say, "this picture was set to this temp and I need to make this image's values white so I have to change the temp by this much"
Didn't you know cameras can talk and think in first person?
 
interesting question; I always assumed:
* if you take the picture in RAW format, "white balance in" won't matter, "white balance out" will always be fine
* if you take the picture in JPG, it could be problematic, as in that case "white balance in" could affect "white balance out"
so I always use RAW, and never had a problem (and I usually use the previous custom white balance to take reference picture for the next custom white balance)

but, as kevinottawa says, maybe the camera reads the "white balance in" from the JPG metadata and compensates for that

in any case, it's easy to test this out:
* take your white balance card out, take 4 pictures of it, using different settings: "RAW+daylight", "RAW+tungsten", "JPG+daylight", "JPG+tungsten"
* record four short clips of your white balance card, using each of those pictures as custom white balance
* compare those short clips (it should be quite easy, you can just look at them on the camera's LCD: if they are not the same, they will differ by a huge amount)
* if they are all be the same, you've proved "white balance in" doesn't affect "white balance out"

I don't have my camera with me right now, can somebody test this?
 
My understanding is that the white balance is done after the image is captured, so the camera starts from the same place no matter what the preset is.

I have never had an issue customizing white balance no matter what preset the camera was using.
 
I've always used AWB to set the Custom White balance and it seems to work. This sunny morning, I went on a white balance test rampage. I shot using Auto White Balance, Custom WB with a Grey card, I used the Daylight preset and also the 5400k and 5600k settings.

I tried it several times a piece and I noticed that Custom was the best and Auto White balance was the 2nd closest. All the presets looked VERY OFF to me. None were even close IMO.

The Flo Light 4000k preset for some reason is pretty color accurate with Tungsten lights. I have never been able to Custom WB to Tungsten on the 7D. It always comes out green no matter what. And my friends 7D is exactly the same way.
 
You must log in or register to reply here.
Back
Top