The white point is important when it comes to getting the colors correct in an image. This is because, with the human eye, everything is relative. In particular, the human eye relates tone and color to the brightest point in an image.
White Point
The point of minimum density i.e. Dmin in traditional photoprocessing parlance."
White Balance ...
White Point: The white point option determines the color of white used for the monitor. Similar in function to the white balance option on your camera, the white point specifies the color temperature the monitor should be calibrated to.
White Point
A term used to describe color temperature as it relates to the luminance of the brightest white that a device can display. It also refers to the reference (or target) white of the illuminant.
White point. In image editing, the lightest pixel in the highlight area of an image.
White point adjustment
An adjustment made that will determine the amount of highlight detail in an image. It is considered proper to set the white point so that the lightest part of an image will only just have zero detail.
White Point
- 2500 - 7500 K in 100 K steps (depending on selected Lighting)
Lighting ...
The White Point, Black Point and Gamma are the most important sliders for realism effects. Increase Gamma to make the images look more real.
Select the white point in the Blue curve, and use the arrow keys to move the point to the left (Figure 14). Watch the #2 sampler numbers, and stop when B=245. This one move has cleaned up the white and improved the overall contrast of the image.
Check the white point color balance.
This one is not so easy. If there is something that is obviously white in your image, then it's a little easier. If there isn't, then you'll have to use trial and error.
Same for the new white point. About half way to the right hand start point of the graph would do nicely for a new white point.
White point
[edit] References
^ Phyllis Davis (2000). The Gimp for Linux and Unix. Peachpit Press, 134. ISBN 0201702533.
^ Adobe Creative Team (2000). Adobe Photoshop 6.0. Adobe Press, 278. ISBN 0201710161.
^ Blain Brown (2002).
Instead, Adobe provided us a hidden solution to tell accurately what is going on as we move black and white point sliders. With the "Preview" box checked, hold down the Alt-key (Option key on the Mac).
- The next section includes White Point, Black Point and Gamma. White Point affects highlights-use caution with it. Black Point adjusts the blacks in the photo-be sure they're strong enough.
Colorimetric comes in two versions, relative and absolute (the difference is based on whether the white point is adjusted or not).
26 Bring the white point arrow in to 185. Then Option click the white point arrow to split them, pulling one half of the arrow back to 205. Click OK.
27 If necessary, the opacity may
be varied to reach your desired adjustment.
The Exposure slider is very much like the white point slider in the PS levels dialog.
You are going to set the white point by adjusting the contrast and the black point by adjusting the brightness controls on the monitor (CRT) and you do this while looking at four white blocks and then four black blocks.
(lower right hand corner, far right eye dropper)Set White point and you are now a pro because no matter what light your using it will come out crisp and very real white with the other colors balanced to that white point.
In auto mode, complex algorithms in the camera decide where the white point is. This is usually fairly accurate, though under cloudy conditions it may cause blue-tinged images.
'Black Point' and 'White Point' set the high and low clipping levels in the image. Again, I tweaked them slightly from the default.
Most good digital cameras let you set the white balance - the assumed white point - of your subject at will. The EOS digital D-series cameras all let you use auto white balance settings or preset settings for common lighting situations.
You can simply adjust your white point to change the color balance. For example, if you lower the white point to, say, 3200, you are telling the camera that you want yellowish light to be shown as white noon-type daylight.
This increases the contrast of the area, as the white point of the histogram matches the white point of the area, and the same with the black point.
With Levels, you can change the black point, white point, and midpoint (aka gamma). With the possibility of doing this for each of the channels separately, this is often all the control you need.
Synthetic profile
An ICC profile created in Photoshop with specific gamma, white point, and primary values, used for correcting images with severe exposure problems.
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Using Adobe Photoshop's Black and White Point Adjustments
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A good functioned digital cameras may have "white preset" which measure the "white point" from a white sheet of paper or card and use it to correct all images unless you reset it.
Use the Quick Selection Tool to select the sky. Add a Levels Adjustment Layer via Layer>New Adjustment Layer>Levels. Drag the White Point slider to the left to brighten the highlights and modify the midtones with the central (Gamma) slider.
This rendering intent is most often used in proofing. It preserves the native device white point of the source image.
RGB
RGB ...
black point
scanned color that produces values of 0, 0, 0 in a acanner. (Ideally, black point is 0% neutral reflectance or transmittance), also refer to white point.
lens reflex) camera with a long lens rather than using a point-and-shoot or a single-use "disposable" film camera. In fact, with a point-and-shoot or single-use camera, you can get an image of the moon but it will likely be a tiny white point rather ...
 See also: Image, Photoshop, Light, Camera, Time
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