GIMP
Have you ever wished there were a free version of Photoshop? Well, there is — kind of. It’s called the GIMP, but it comes with a couple of provisos: You must have X11 installed on your Mac and you must be prepared for a steep learning curve. The GIMP is not exactly Photoshop, but it you may find it comes close enough.
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Image Tricks
Use the power of Tiger’s Core Image to apply a number of cool effects to your pictures. You can also generate original images.
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ImagePlay
Easily add effects to your images with ImagePlay. Reflect, shimmer, glow — the list goes on. And you’re not limited to just one effect. You can layer them one on top of the other. A guided tour makes learning easy.
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LiveQuartz
A free image editor based on layers and CoreImage filters. You have the layers on the left and the filters on the right of the window. To edit an image, just drag it into the layers’ list and it will be added as a new layer.
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PhotoRetouch DigiCam
PhotoRetouch DigiCam does indeed touch up your photos. Improve them or warp them for fun. This free version has a lot more features than you might expect.
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PixelNhance
PixelNhance is one of the best of the bunch, but it’s been hard to find since the developer has discontinued it. Caffeine Software has a download link that works as of this writing, but unfortunately it hasn’t been reliable in past. In addition to the link below, you can try this one at 5 star.
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Seashore
It’s full of cocoa and open source goodness, so Seashore is worth keeping an eye on this program as it develops to its potential — a free version of Photoshop?
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