17
Curve
If your original is too dark or too light, you lose vital detail
after scanning. You can fix them up using curves.
Curve function is applicable to grayscale and 24/48-bit
color images. Simply put, if you knew how to use Adobe®
Photoshop® or any other equivalent softwares’ curve
function, you can safely skip this section.
Applying a curve to an image is to enhance favored
brightness ranges at cost of others. Like you can enhance
the shadow at cost of the highlight and midtone. If done
properly, you can energize a dull image using curves without
sacrificing the overall image quality. To write a curve, simply
place an anchor on the diagonal line and adjust its position.
Add more anchors if you have to write a more complex
curve. You can also remove anchors.
To emphasis shadow, raise the anchor; to emphasis highlight,
lower the anchor; to emphasis midtone, write an S-shaped
curve; to decrease contrast, write an inverted S-curve.
Experts apply curves to individual channels to color-correct
an image. Usually this is done to a CMYK image to be
printed.
add/remove anchors
