Overlay layer on photo, and export result at higher resolution than the native display.

Question

I want to take a photo with the device's camera, overlay a CALayer on top of it, and export the photo at the native resolution of the device's camera.

The best solution i could come up with so far, was to overlay the CALayer on top of the UIView, and capture the current view state using [CALayer renderInContext:]. However the result of this will be at the devices native screen resolution, not the original resolution of the camera.

Any better suggestions?

Thanks as always