When you choose
a different color mode for an image (Image > Mode >
[image mode]
), you permanently change the color values in the image.
You might want to convert into a different mode for several reasons.
For example, you may have an old scanned photo in grayscale mode
in which you want to add color, so you would need to convert it
into RGB mode. Before converting images, it’s best to do the following:
-
Edit as much as possible in RGB mode.
-
Save a backup copy before converting. Be sure to save a copy
of your image that includes all layers in order to edit the original
version of the image after the conversion.
-
Flatten the file before converting it. The interaction of
colors between layer blending modes will change when the mode changes.
Note: Hidden
layers are discarded and images are flattened automatically when
you convert them into bitmap or indexed-color mode, because these
modes do not support layers.