MichaelT
20th June 2004, 04:13 PM
This FAQ will be expanded with screen shots and pictures over the next few days. Please stop back. It will be marked as updated as thigs are added.
Draft 1.0 20 June
It is essential in the digital photographic world to achieve a proper White Balance in your pictures. This assure that the entire color "balance" of the picture is correct. The reason for the need for a White Balance, is that unlike our eyes which automatically adjust to the color of the light and always render neutral (white and gray) objects as neutral, the sensors and circuitry in digital cameras do not. So they "see" the color of the light. As such a a photograph taken in tungsten light will be rendered as "orange" and a picture taken in daylight will be render towards Blue. While cameras have an "auto" White Balance feature, they are close but no cigar in many instances. Especially when shooting in low Kelvin environments such as Tungsten light.
WhiBal works in the following way. The Gray cards in the WhiBal have been engineered such that they will always reflect exactly the colors that are bounced off of them. They are precisely neutral. So if the light is a bit orange they will precisely reflect that orange light to the camera. So in effect we are able to "capture" the exact lighting conditions that existed in the scene that you were photographing.
In practice, a WhiBal exposure is made by photographing the WhiBal under the same light that your main subject will be in. This then become a reference photograph that is used later in the production process. After the WhiBal shot is taken, the card can be put away and the normal photographs are taken.
If you are shooting in JPEG mode, you should try to match the camera WB setting as closely as you can to the lighting conditions. Alternately you can use the Auto WB setting if the camera works well in that mode. In any case the object is to have the JPEG capture be as close to the real WB as possible so that the changes that will be made when the WhiBal reference shot is used to fine tune the White Balance will be as small as possible.
If, however, you are shooting in the RAW mode, it does not matter what the camera WB is set to. It will have no effect on the quality or ability to set a PERFECT White Balance using the WhiBal reference shot. However by setting the camera close to the color of the light in the scene, the photographs will look closer to reality before the WB process is done, so this might help in the selection process, or if you need to get quick proofs out before the fine tuning is done. The important thing to note about using RAW is that a PERFECT WB can be achived with NO loss of quality, where in JPEG mode a perfect WB cannot always be achived, and there will always be a loss of quality when tuning the White Balance of a JPEG.
JPEG Production
In Photoshop or other image editor, load the WhiBal picture that was taken under the same lighting conditions as the pictures that you wish to White Balance properly. Using the Curves, or Levels tool (according to what is available in your image editor), select the "Gray point" eyedropper. Click on the DARK Gray WhiBal card. The picture should now relfect the proper White Balance for that scene and lighting. Save this setting and label it appropriately. Now whenever you are editing a photo taken under the same light, load that curves or levels setting and that same WB correction will be applied to the new photograph.
RAW Production
Within your RAW conversion software, simply load the WhiBal shot and use the WB click or pick tool and click on the WhiBal LIGHT Gray card. This picture will now be perfectly White Balanced. Of course if you wish to tweak if ro personal taste most RAW software will allow you to do this from the perfect starting point. Now use the ApplyTo function or the copy setting function to copy the WB setting to all of the pictures taken under the same lighting conditions as the WhiBal shot. Done!
More will be added to this post and a specific workflow will be shown for JPEG, C1 RAW Conversion Software, as well as Photoshop CS.
Draft 1.0 20 June
It is essential in the digital photographic world to achieve a proper White Balance in your pictures. This assure that the entire color "balance" of the picture is correct. The reason for the need for a White Balance, is that unlike our eyes which automatically adjust to the color of the light and always render neutral (white and gray) objects as neutral, the sensors and circuitry in digital cameras do not. So they "see" the color of the light. As such a a photograph taken in tungsten light will be rendered as "orange" and a picture taken in daylight will be render towards Blue. While cameras have an "auto" White Balance feature, they are close but no cigar in many instances. Especially when shooting in low Kelvin environments such as Tungsten light.
WhiBal works in the following way. The Gray cards in the WhiBal have been engineered such that they will always reflect exactly the colors that are bounced off of them. They are precisely neutral. So if the light is a bit orange they will precisely reflect that orange light to the camera. So in effect we are able to "capture" the exact lighting conditions that existed in the scene that you were photographing.
In practice, a WhiBal exposure is made by photographing the WhiBal under the same light that your main subject will be in. This then become a reference photograph that is used later in the production process. After the WhiBal shot is taken, the card can be put away and the normal photographs are taken.
If you are shooting in JPEG mode, you should try to match the camera WB setting as closely as you can to the lighting conditions. Alternately you can use the Auto WB setting if the camera works well in that mode. In any case the object is to have the JPEG capture be as close to the real WB as possible so that the changes that will be made when the WhiBal reference shot is used to fine tune the White Balance will be as small as possible.
If, however, you are shooting in the RAW mode, it does not matter what the camera WB is set to. It will have no effect on the quality or ability to set a PERFECT White Balance using the WhiBal reference shot. However by setting the camera close to the color of the light in the scene, the photographs will look closer to reality before the WB process is done, so this might help in the selection process, or if you need to get quick proofs out before the fine tuning is done. The important thing to note about using RAW is that a PERFECT WB can be achived with NO loss of quality, where in JPEG mode a perfect WB cannot always be achived, and there will always be a loss of quality when tuning the White Balance of a JPEG.
JPEG Production
In Photoshop or other image editor, load the WhiBal picture that was taken under the same lighting conditions as the pictures that you wish to White Balance properly. Using the Curves, or Levels tool (according to what is available in your image editor), select the "Gray point" eyedropper. Click on the DARK Gray WhiBal card. The picture should now relfect the proper White Balance for that scene and lighting. Save this setting and label it appropriately. Now whenever you are editing a photo taken under the same light, load that curves or levels setting and that same WB correction will be applied to the new photograph.
RAW Production
Within your RAW conversion software, simply load the WhiBal shot and use the WB click or pick tool and click on the WhiBal LIGHT Gray card. This picture will now be perfectly White Balanced. Of course if you wish to tweak if ro personal taste most RAW software will allow you to do this from the perfect starting point. Now use the ApplyTo function or the copy setting function to copy the WB setting to all of the pictures taken under the same lighting conditions as the WhiBal shot. Done!
More will be added to this post and a specific workflow will be shown for JPEG, C1 RAW Conversion Software, as well as Photoshop CS.