Below is a list of the camera equipment I use, and a little reason why I chose it:

  • Canon EOS 6D (Full-frame): I chose this camera body for a few reasons. The first being, it was a Canon and all my lenses are EF mount. Changing manufacturers would be incredibly expensive since I'd have to buy all new lenses. The second being, I wanted a full-frame camera body to take advantage of the better image quality and lower ISO-to-noise ratios. Finally, a full-frame sensor gives more options when it comes to wide angle work, because it's not cropping the light (image) projected by the lens. This is quite helpful with landscape photography.

  • Canon EF 16-35mm f/2.8L II USM: I love taking pictures of landscapes and the night sky, and needed a new wide angle lens. My old lens minimum focal length was 28mm and just wasn't wide enough. Although there are many lenses to chose from, this lens got fantastic reviews and covered the focal lengths I was interested in. It's a stunning lens. The only draw back is it's a bit soft wide open at 2.8 when near 16mm and 35mm, but quickly corrects stopping down one stop.

  • Canon EF 100mm f/2.8 USM Macro: I bought this years ago, and use it on occasion when doing stuff other than landscapes. While I do enjoy macro photography, my heart is much more set on landscapes.

  • Canon EF 28-135mm f/3.5-5.6 IS USM: I bought this lens about 15 years ago with my first Canon Elan film body when I first got semi serious about photography. A the time, it was a good point-and-shoot lens that covered many of the more common focal lengths. I rarely use it anymore.

  • Canon EF 100-400mm f/4.5-5.6L IS II USM: This is my newest purchase. I spent many nights comparing this lens to the Sigma 150-600mm f/5-6.3 DG OS HSM Sport and I made up my mind only after writing down the pros and the cons for the type of photography I'm interested in. But right from the start, let me say both lenses are great and will produce very good results. I wrote my reasons below based on the research I performed (others may be interested):

Pros

  1. The Canon is more than a couple pounds lighter. This will make a big difference when hiking and packing for trips.
  2. The Canon is shorter in length and won't be as out-of-balance when fully zoomed (extended).
  3. The Canon will fit in my existing camera travel bag. The sigma would have to be packed in its own additional bag (for hikes).
  4. The Canon's Image Stabilization gets up to 4 stops as opposed to the Sigma's 2 stops. This will make a big difference when hand-holding.
  5. The Canon will be much easier to hand-hold than the sigma. The Sigma is a huge beast and will require a mono-pod or tripod, especially with smaller apertures.
  6. The Canon slightly edges out the Sigma on sharpness.
  7. The Canon is much better with distortion and vignetting (light falloff in the corners). The Sigma needs to go to f/11 before it gets better.
  8. The Canon is f/4.5 and holds that aperture over a larger focal length than the Sigma. The Sigma is f/5.0.
  9. I could always get a 1.4x Teleconverter and increase the focal length to 560mm, almost matching that of the Sigma. Could also get a 2.0x teleconverter for an effective 800mm focal length (would sacrafice image quality, though).
  10. The minimum focus distance is much shorter on the Canon (3.2 feet) than the Sigma (8.5 feet).

Cons

  1. The Canon is slightly more expensive.
  2. The Canon is 400mm rather than the Sigma's 600mm.
  3. If using a teleconverter to increase the focal length to match the Sigma, the autofocus on the Canon 6D won't work anymore.
  4. If using a teleconverter, the Canon will lose some of its sharpness and IQ, but it should still be really close to the Sigma.