Its about 15 000 pixels, I know c4d can handle a image this size, the thing is that I use a local render farm and I redistribute the render through team render. If I render 15k straight is very slow to render and some clients just stop or refuse to render. If I use camera tile rig it renders incredibly fast.
So, that camera rig in my opinion is the best "tool" regarding render speed in large scale still images. Its a shame now with the update not working that well 😞