browndog

That's a good question. They're too close together to be 15mm rails but they do look like they are for some kind of attachment. It will be interesting to see as more information is released.

I don't think those are for rails. If I'm shooting with the base then I will need a battery, external recorder, likely an external monitor, matte box with ND filters, focus gear or remote focus motors, audio gear, etc., To support all of this, the rails need to extend through the base and provide the flexibility to mount some of the gear on the rear. Screwing rails into the front would not be sufficient for this kind of setup. I'd be concerned about putting a big zoom or even a heavy anamorphic like a Lomo 35mm Roundfront on rails that are screwed into the base. Also, if I mount the rails below the base, then they will be a long way from the lens and I'll have to mount another set of rails higher in the front with an adapter. This complicates things when they could just include 15mm holes in the body of the base adapter. This camera is a game changer, but we need to learn more about how the camera can be rigged to adapt to various production environments.

This base would be much more useful if Panasonic had thought to include holes and clamps for rails. It will be difficult to rig this camera with a matte box, focus gear, and other accessories. I'm curious to see what solutions people come up with to address this. Ideally, the brick could have been designed with cables, so that it could be mounted somewhere other than directly underneath the camera. All in all this is an incredibly exciting camera.