GIMP is a free program for such photo retouching, image composition and image authoring. Essentially it's the closest thing to Photoshop you can get for free.
GIMP vs Clip Studio Paint opinions
Lack of important options and optimization for drawing, and really poorly and ugly UI
Krita is a professional Free and open source (FOSS) painting program. It is made by artists that want to see affordable art tools for everyone within concept art, texture and matte painters, illustrations and comics.
Krita vs Clip Studio Paint opinions
a great software for poor artist but very powerfull to drew . i'm like it
It has a full list of features, and it's free!
I have been using Krita for 4 years and just jumped to Photoshop . The features are very similar to Photoshop so It really made me feel right at home after I jumped from it. Best alternative to Photoshop.
Completely free and very powerful
I really like the fact that it includes animation, even though it's so much cheaper than clip studio paint!
Krita's developers are also working on the animation function of Krita. It's good for animating without audio, since the audio function may not always work for your device. Jesse J. Jones made a nice tutorial on Youtube for Krita.
Inkscape is an Open Source vector graphics editor, with capabilities similar to Illustrator, CorelDraw, or Xara X, using the W3C standard Scalable Vector Graphics (SVG) file format.
Inkscape vs Clip Studio Paint opinions
inkscape is nothing like manga studio at all
Inkscape does vector. Clip Studio does bitmap.
Inkscape is an Open Source Vector Graphics Editor as the description implies. However, Clip Studio Paint main focus is bitmap. Inkscape is similar to Illustrator, Corel Draw and other vector graphics editors and is a good software on it's category, but it doesn't possess the same features for bitmap drawing as Clip Studio Paint, Paint Tool Sai or even Photoshop
Inkscape is primarily a a Vector Graphics Editor, not predominantly bitmap like Clip Studio Paint. While CSP does have "Vector Brushes" and uses a selection of vector objects to create speech and thought balloons, these are really ways of applying brush tips and shapes in a rescaleable way, and a full set of vector manipulation is not available.
Inkscape is more an Alternative to Corel Draw and Adobe Illustrator, NOT Clip Studio Paint.
it is a good alternative because it possesses almost all the same functions that clip studio paint and for free
MyPaint is a fast painting program with an emphasis on full-screen use. It lets you focus on the art instead of the program. You work on your canvas with minimum distractions, bringing up the interface only when you need it.
MyPaint vs Clip Studio Paint opinions
not made for drawing manga
Storyboarder makes it easy to visualize a story as fast you can draw stick figures. Quickly draw to test if a story idea works. Create and show animatics to others. Express your story idea without making a movie.
GPS (aka Gimp Paint Studio) is a collection of brushes, patterns, color gradients, accompanying tool presets and dynamics. Tool presets are a simply saved tool options, highly useful feature of the GIMP.Discontinued
The project seems to be no longer developed. Last version, 2.0, released in August 2013, can be still downloaded from GitHub.
Gimp Paint Studio vs Clip Studio Paint opinions
It's NOT discontinued. They just release 2.10 earlier this year.
Qaquarelle is a very young opensource Qt4-based painting application that is supposed to provide a native way of painting with emulated traditional instruments, including watercolor simulation, full support for tablets and OpenGL-based processing in GPU.
Latest vsersion: 0.0.4 from 2010-02-09. See https://sourceforge.net/projects/qaquarelle/files/
Paintstorm Studio is created for professional digital painting. And a major role in this program play the brushes. We did our best so that you can easily and quickly adjust the brushes suitable for your painting style.
gpaint (aka GNU Paint), a small-scale painting program for GNOME, the GNU Desktop Environment. gpaint does not attempt to compete with GIMP, it is just a simple drawing package based on xpaint, along the lines of Microsoft Paint.