In your honest opinion is there much of a difference between manufacturers of digital SLR cameras? Is it better to look only at the two biggest being Canon and Nikon or are the other ones worthy of a look too like Olympus and Sony?
As usual in photography, it depends 🙂 While Canon and Nikon dominate the professional DSLR market, other manufactuers including Fuji, Leica, Olympus, Pentax, and Sony have some nice products. If you are looking to buy a camera and one lens for recreational photograhy, all of them are worth of consideration.
On the other hand, if you’re an advanced amateur or plan to get into professional photography, you should carefully consider the range of lenses that the manufacturer offers. One of the primary advantages of the DSLR is that you can change lenses: You might want an ultra wide lens for landscapes, a long telephoto for nature, and something inbetween for portraits. If you do a lot of photography in low light, you may want f2.8 zoom lenses or even faster prime lenses.
In the consumer space, people generally buy a camera, while professionals buy a system. Once you have purchased a bunch of expenses lenses, the last thing you want to do is change camera manufacturers. Nikon and Canon both offer an extensive range of lenses, and other lens manufacturers like Sigma offer lenses for Nikon and Canon cameras.
When it comes to Nikon and Canon, both have some great products. There are historical, practical, personal, and religious reasons why some photogs choose one over the other, and fierce competition results in a perpetual game of leapfrog. I personally shoot Nikon, but I’ve tested a few Canon DSLRs and had good results.
I tested a Pentax DSLR a year or so ago, and it produced images comparable with other DSLRs in it’s price range. I also tested an Olympus DSLR and it produced really nice images. Olympus introduced the first DSLR with live viewing on an LCD monitor that can be folded out for viewing from above like a waist-level viewfinder, which was great for photographing the kids. Other manufacturers have also introduced features that might interest you.
In summary, if you’re comparing apples to apples, you might not notice a big difference between manufacturers, especially in entry-level DSLRs. The brand differences emerges when you’re looking for higher-end gear and a wide variety of lenses.