CanonRumors.com has been entertaining rumors of a crop sensor camera to come for the RF mount. Now it putting its weight behind the assessment that a particular rumor is true; in particular that such a body will be released in the late parts of 2022.
Crop bodies – ones that have a smaller sensor than the traditional “full frame,” 35-millimeter format – have traditionally been used to save manufacturing costs. Especially early in digital photography, when one wafer of sensors at the factory would often have problems on its service, and having smaller sensors etched into that wafer meant a much lower rate of ruined sensors. At this time, the sensor was often a third or more of the cost of materials for a full frame camera.
Today’s manufacturing methods have decreased the spoilage areas on wafers, reducing the relative cost between full frame and crop sensors, but because crop sensors are smaller, there will always be more crop sensors fitting on a single wafer, and the cost per chip will be lower – just not by as dramatic an amount.
There are two continuing reasons why some people prefer crop sensors. They effectively act like a teleconverter, increasing magnification at the expense of having fewer photons per photo site. For reach-limited uses, like wildlife photography, this can be convenient. The crop bodies are also often smaller – and perhaps more importantly – the lenses they use can be significantly smaller, and potentially cheaper.
Canon’s previous crop lens line never really pushed the high-performance angle, although users of the 7D series did sometimes employ full frame lenses on crop bodies to enjoy the extra magnification. Canon primarily sold crop bodies as entry level cameras, and produced crop lenses designed to be cheap. It was third party vendors that made very high quality crop-designed glass, such as Sigma’s famous 18-35mm Art lens, still a favorite among filmmakers.
It remains very unclear if an upcoming Canon crop camera would come to serve the 7D series audience or the entry level audience. Today’s entry level cameras in the RF mount sell for just uncer $1,000 and use relatively old full frame sensor. A crop version of that could knock down some tens of dollars off that bill of materials, but Canon might also price such a camera a few hundred dollars lower just as a means of price stratifying their camera lines. This is perhaps the more likely outcome, which would mean that any crop-only lenses would likely be variable-aperture kit lenses.