Hi, is there any way to retime a camera (or an alembic with camera) with the retime node? I would like to link the retime of a simulation cache to retime a camera move for bullet time effects. I can extract the transform point from a camera and connect that to a retime, and link it to a new camera with a null. This kinda works, but I don't know how to extract camera rotations. Any ideas?

You shouldn't have to use SOPs. The CHOP context is made for this and even has a retime node. The object and fetch nodes can be used to get the transforms and zoom animation respectively. Chops can then export the modified channels to a new camera, or the original camera if it doesn't have any parents. You can technically use the original camera even if it has parents, but in that case constraints need to be used rather than chop exports, which is a slightly different code path that replaces the object's transform completely.

Retime node in chops is not the same, as the one in sops. Is difficult to link them.

The retime sop can be used in ‘time’ mode, then the chop containing the time curve can be exported to that parameter as well as connected to the retime chop. When the retime SOP is in linear interpolation mode, it should match chops interpolation.