Canon Mount Adapter EF-EOS R (New)

This is an excellent product if you have a Canon R series mirrorless camera and would like to continue to use your EF as well as EF-S lenses. Here's an interesting point....If you're using this adapter on a Canon FULL frame R series camera with the adapter and are attaching a Canon EF-S lens, the full frame camera senses this and switches into "cropped mode". What this does is temporarily change the full frame camera into an APS-C camera while an EF-S lens is attached to the adapter. Here's an example...If you're using a full frame Canon R5 (45 mp sensor) and want to use an EF-S lens, the result will be a lower resolution image. In "crop mode" the R5 would produce a 17.5 mp image because the crop factor (1.6) is applied to BOTH the vertical as well as the horizontal. The result is 45/(1.6 x 1.6) = 17.5 mp. 17.5 mp is still a sizeable image but you should be aware of the downsizing of the image. This ONLY applies when using a Canon FULL frame R series camera with the adapter and an EF-S lens. There is NO image megapixel loss when using standard EF lenses with the Canon R series cameras and the adapter.