Do you mean CTRL + G which is the shortcut for the Insert
Image dialogue?
Inserting the images that way, you are inserting a copy of
the original so the resolution cannot change. It sounds like your
originals are jpgs with a high number of colours and as if your
images are going in as GIF files as they have a limit of 256
colours. I can't see how inserting them using the dialogue box can
change them so check the file format of your originals and the
format of the files in the project and post back.
If you were inserting using cut and paste, that would be
different.
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