GIMP is poor man’s Photoshop. If we consider a simple task such as editing a digital photograph, it’s clear that Photoshop and GIMP can provide very similar working environments but is this free image editing software a good alternative to Photoshop CS3.
For many people, GIMP offers all the image manipulation tools they need so ZDNet examines how far a serious (professional or semi-professional) user can get with GIMP vs Adobe Photoshop.
Although Photoshop just installs out of the box and is ready to go, to get advanced functionality out of GIMP requires some effort on the part of the user. Some standard Photoshop features are possible in GIMP, but require the installation of additional software.
If you use Photoshop to create artwork for print, then you can forget about replacing it with GIMP for now, as GIMP supports only RGB colour. CMYK support is due to be added, but for now it’s not available.
So can free software really compete with Photoshop? For the vast majority of ordinary users the short answer is certainly ‘yes’. However, for graphics professionals — that is, Photoshop’s target market — the answer has to be a resounding ‘no’. Link.