Tas_mania wrote:
I think of Krita as software that replaces a sketchpad but maybe I'm wrong?
Doing a traditional sketch/watercolor and then photographing it with a digital camera essentially digitizes it producing a result similar to Krita.

A 'sketchpad' is not really covering it - Krita is a full art creation and editing suite these days.
Krita actually can do pretty much everything that GIMP can, at least for my usage. It has a smaller selection of custom filters than the latter and don't have the long history and big community of scripters etc. But things like GMic are available as a menu item. The only thing I really lack is the ability to clone between layers (but I think that was being looked at).
Overall though, Krita's main focus is on _creating_ artwork - digital painting, drawing and the like. It also has quite powerful animation features. Unless that changed recently, as far as I know, Gimp devs have stated quite clearly that their primary focus is on photo manipulation; that is, _editing_ existing artwork rather than creating it.

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Griatch