This will give current 5D owners a good idea of what to expect if they decide to upgrade, and also give Canon users an idea of what (if anything) the extra money for the EOS-1Ds Mark III might buy them in terms of image quality. First we will compare the 5D Mark II with the original 5D, then to the EOS-1Ds Mark III, which has a similar sensor and shares the 5D Mark II's 21 million pixel count. In this comparison we are only looking at full frame DSLR cameras. There is now a lot of choice for those looking for a compact, relatively inexpensive full frame DSLR.
All this in essentially the same size body as the original, and at a similar price to the Sony and Nikon cameras. The new camera promises to compete with the D700 on ISO performance (with a range from 50 to 25600), and with the A900 on resolution. In answer to these, Canon finally announced the long awaited follow up to the EOS 5D in September 2008. In other words, a camera that aims to leapfrog both its direct rivals, either in terms of resolution (in the case of the D700) or features (in the case of the DSLR-A900.
Later that year at Photokina, Sony joined the party with the A900. So here is the 5D Mark II, which punches high in terms of both resolution and features, headlining: 21 megapixels, 1080p video, 3.0' VGA LCD, Live view, higher capacity battery. In 2008 Nikon entered the full frame market with the D3, quickly followed by the D700. When the original 5D was released 3 years ago, it stood alone as the only 'compact' full frame camera available, and for almost 3 years was also the only 'affordable' option for users who wanted the benefits of a full frame camera without the high price of a Canon 1Ds series body.