I carry a Nikon D5000 digital single lens reflex camera. Actually I carry two. I found when I carried one camera I was constantly wishing I had a different lens attached. For a time, I carried extra lenses, but that was only somewhat better since when the opportunity came to shoot a subject that I would prefer with the other lens, I still had to stop, fish out the alternate, remove lens one and put it away, then install lens #2. So, unless the subject was perfectly static, more often than not it was too late. Even with landscape photos the light can change, a cloud come over and the photo seen in my mind is gone.

So I acquired a second camera body; this one I found gently used for about half of the cost when my camera was new. I intentionally chose a second unit precisely like the first so the controls and settings available would be identical between the two.....when switching cameras, there would be no confusion and which unit could perform which function. I carry one with an 18 - 55 mm variable for panoramic scenes or shots requiring little if any magnification. The other camera is a variable long lens, 80 - 300 mm. The telephoto lens is actually quite useful for shooting flowers --- I get really nice close-ups of blooms without needing to stand right on top of the subject.

I invested in a vest that allows me to carry one camera on my chest and the other on my belt. each camera is held in place by a button attached to the bottom of the camera battery plus a safety strap for extra security. My hands are free when walking, but either camera is immediately at hand when the next "money shot" presents itself.