CS4 Camera RAW White Point

Question

Setting White Point in Camera RAW 5.7 CS4
I am trying to make pictures out of scanned old slides/negatives which often have colour casts.
Some pictures do not have a suitable white spot for setting the point.
I often find that the "As Shot" or any of the default settings do not look right.
Please what is the best way to set the white point for these ?

Answer 1

Photoshop, or even Elements, would have more options than Lightroom for fixing colors or a color-cast in images that have not been added by the scanner, but is already in the images, themselves, a color cast usually caused by different rates of deterioration of the various pigments in the photo paper or film.
Trying the different Options in the Photoshop Levels command can be helpful. 
You can tweak the RGB channels differently in Photoshop Curves.
Elements has a Remove Color Cast command that works for simple cases and is similar to the Auto WB in LR or ACR.
Sometimes you need to duplicate one of the color channels and substitute it for one of the other color channels.  For example if the red is entirely faded, then duplicate the blue channel and paste it into the red channel and see how things look, or perhaps use the green channel, instead, depending on the mix of colors in the original.  There are techniques for adjusting skintones at the expense of other colors in the image.
There are tutorials for fixing underwater images that would be somewhat applicable to photos heavily faded by prolonged exposure to sunlight or indoor UV sources.
Tweaking the HSL sliders in LR or ACR can be helpful if the image is mostly fixed by prior adjustments.