White Balance in camera 101

Hi all,
I would like to have you opinions on white balance setting in camera. My camera is a 40d, but I guess they all have a similar white balance option.

I am looking for a cheap and efficient way to do my custom white balance in camera (not at the post processing stage). So far I have two basic options.

1. Coffee filter: I take a picture through a coffee filter on the lens. I then set the custom white balance to that picture. (see http://www.flickr.com …iscuss/72157603​805698706/)

2. I take a picture of a white object (in my case it is a piece of white paper in my lens cap) and use it to set the white balance.

I found some difference of opinion on how to set the white balance. Should we take the picture in direction of what we want to take picture, or take a picture in direction of the "photographer" position in order to receive the same light as the photographed object will receive.

Let me know what work best for you,

Is setting WB "to taste" out of the question, i.e. you have some professional task or you want consistency across a large group? I would get a gray card for those cases, making sure that if lighting changes I take a new shot of the gray card.

Then, in Digital Photo Pro, just click the WB eyedropper on a part of that gray card and save that as a recipe. Done.

Taking a picture of a white object won't work. You want a gray object. Keep in mind that if your gray balance photo is noisy, chroma noise might throw the values from one gray pixel to the next. Also, if the gray card isn't lit like the subject of your photo, gray values may be off again. Even lighting on the gray card is the best.

Well, hang on -- white will work as well as gray as long as the "target" is "color-neutral".

The idea is to get the scene lighting -- either the target in the scene or, as you mentioned, something like a coffee filter or an ExpoDisk that will let the scene lighting into an exposure.

Just make sure the target light fills up a good portion of your view and use it to set the Custom White Balance. Or, as was selected, you can use it in post processing, but you said you didn't want to go that route...

I just shoot raw and adjust to taste in post. Nothing I shoot would be considered color critical so I really don't care if I nail it in-camera or not.

I am having an issue where whenever I do a custom white balance the color turns green...the white balance for some reason is green...

Any ideas?

Umm, either you're getting the target way off or you need to send your camera in?

SleepingPachuco wrote in post #13197443
I am having an issue where whenever I do a custom white balance the color turns green...the white balance for some reason is green...

Any ideas?

Mine does too, but it's intentional because I use the Uni-WB custom. Green cast is an indication that no WB is being applied, that is the native color before WB because the sensor is much more sensitive to green than to red or blue. (Uni-WB is a way to trick the camera into doing a zero WB.)

Describe how you do a custom WB.

http://www.bhphotovide​o.com …k_1903061_Gray_​Cards.html

http://www.bhphotovide​o.com …m_White_Balance​_Lens.html

I aim towards subject

I prefer the coffee filter method.. (Except I use the translucent white lids that fast food outlets provide with their paper drink cups ).. Grey cards work, (I have one of those too), but I find the 'coffee filter' is better for wide open spaces with light coming from many directions.

When I did that for the first time with my 40D, I was confused, too. I thought it might have been the flourescent lighting I was trying to white balance under.

SleepingPachuco wrote in post #13197443
I am having an issue where whenever I do a custom white balance the color turns green...the white balance for some reason is green...

Any ideas?

SleepingPachuco wrote in post #13197443
I am having an issue where whenever I do a custom white balance the color turns green...the white balance for some reason is green...

Any ideas?

Hi,

I had this happen as well when using an ice surface to set a custom WB. I was told to shoot at 1/60th of a sec to sync with the arena lights. That worked for me - but not sure if it is applicable in your case.


TB

tzalman wrote in post #13197685
Mine does too, but it's intentional because I use the Uni-WB custom. Green cast is an indication that no WB is being applied, that is the native color before WB because the sensor is much more sensitive to green than to red or blue. (Uni-WB is a way to trick the camera into doing a zero WB.)

Describe how you do a custom WB.

Hi,

Why would you want to do a zero WB?

General_T wrote in post #13199647
Hi,

Why would you want to do a zero WB?

Because it gives you an unbiased histogram when used in conjunction with a neutral camera style.

An unbiased histogram allows you to be sure you are capturing the maximum dynamic range.

General_T wrote in post #13199647
Hi,

Why would you want to do a zero WB?

Because RAW is not white balanced. Moreover, when the image is white balanced during jpg construction the method used is to multiply the red and blue channels. For sunlight, shade, etc., blue is moderately boosted but red values are more than doubled. For tungsten lighting it is the opposite. If red is doubled, for instance, any original exposure value that would have been more than 128 should become more than 256, but can't do so because the limit is 255. In other words the red channel is clipped, the histogram runs off the right end and the review jpg starts blinking. But it's not real clipping, the capture exposure is fine and the WB has caused the clipping. Since I am shooting with RAW, if I know that the capture is not overexposed, I will be able to control the effect of the WB during conversion from the RAW.

The camera blindly applies WB without caring about the result; in RAW conversion I control the process. I can control it better if I have an accurate histogram of the RAW data. This is doubly important if I am placing the brightest part of the image as close as is possible to clipping, but without clipping, in order to maximize exposure in the shadow areas and thus maximize DR and minimize shadow noise.

wallace1837 wrote in post #13195951
Hi all,
I would like to have you opinions on white balance setting in camera. My camera is a 40d, but I guess they all have a similar white balance option.

I am looking for a cheap and efficient way to do my custom white balance in camera (not at the post processing stage). So far I have two basic options.

1. Coffee filter: I take a picture through a coffee filter on the lens. I then set the custom white balance to that picture. (see http://www.flickr.com …iscuss/72157603​805698706/)

2. I take a picture of a white object (in my case it is a piece of white paper in my lens cap) and use it to set the white balance.

I found some difference of opinion on how to set the white balance. Should we take the picture in direction of what we want to take picture, or take a picture in direction of the "photographer" position in order to receive the same light as the photographed object will receive.

Let me know what work best for you,

I take a picture of a white card/object (but large enough to fill - or nearly fill - the viewfinder) and its generally placed in the target area not pointed at the photogs position.

I have had great success with this.