I'm still getting to grips with and especially having trouble getting
the white balance in indoors situations right. Any tips on that one?
Yellow pictures are driving me mad
Ohhh, your pictures are outstanding. How did you do that? Personally I have difficulties to balance skin colors with SPP because of that tiny color wheel.
Underexposing and color sometimes bite, you already found it out. The X3F sensor is assumed to see in a different color room than we do, and some color amounts spill over from one primary color into the other. Therefore a color transformation and subtraction of the spill over colors are needed (I hear that, beware). The color transformation can clip values in some situations, and underexposed channels make subtractions difficult, thus introducing noise from the very underexposed channel into the other (does this make sense?). Some folk discovered that under natural light high ISO is pretty good with X3F sensors, and indoors B&W conversions as well.
The conclusion of this is not to expose very close to the limits of the sensor. The histogram is not exactly that what the sensor receives, because it is RGB, after transformation. Unfortunately the three channels are not on display before transformation.
The X3F sensor is balanced for daylight. Under artifical light the contribution of the blue channel (the hard light important for contrasts) is becoming lower with color temperature. You can check this with the histogram. While the red channel is near clipping the blue channel is very weak.
To improve the balance between the channels a blue filter (transmissive for blue light and attenuating red light) helps. You will loose some of the red light while you can lengthen exposure to bring up the blue light for a better balance then.
Another difficult situation is mixed light. You can get it when you shoot indoors in incandescent light (which is very red) and using a flash. For a good color balance you will have to compensate the flash light with a red filter (gel) in front of your flash, while you have a blue filter on your lens. If you don't people close to the flash have ghost-white faces while skin more behind is near natural, or you have natural skin tone in the front and yellow/red faces behind. It is your choice
But why don't you shoot under sun light or even better flash light if you want what people assume to be the best white balance? Using expo dish and similar material will not give you the mood of the situation, because together with the color picker or the camera WB it will adjust colors for daylight. Still you can adjust with the color picker and adjust the color back to 2900K or what color your light had before.
Very unsatisfying results come from flourescent light which has strong peaks in the green. Avoid it when possible.
With Lightroom, probably also Photoshop color balancing is mostly easy. SPP takes longer time, but sometimes results from SPP are superior.
Best regards
Wolfgang
