Perfect! I was looking at those at HD yesterday but unsure if I needed to thread it to something from the hole in the wall. With 1/2" EMT should the
single hole straps be sufficient or do I need double? I'm also gonna need to use a
90 degree elbow. Do I need a waterproof one? I using the Dahua PFA137 box to mount the camera on the wall, but as
@hmjgriffon brought up in another thread, the gap is pretty large between the camera body and the frame that I can easily see water getting in there...
Single hole straps for 1/2" EMT are fine. Look at the 1/2"
LB conduit body instead of the one you linked. A gasket between the cover and conduit body will make it weather tight. I think it comes with a gasket, if not you can buy it separately. Then use
these EMT rain tight connectors. I'm not familiar with Dahua junction boxes, but it appears from the pictures that the outlets/holes, or hubs, are 1/2" USA trade size ? Maybe someone else here can confirm.
If you can enter into the back of the junction box then no need for a conduit body and EMT. Then just caulk the back of the junction to the wall surface.
I would as many have recommended to use the coax seal tape, rubber vulcanizing tape, to wrap your connections in the junction box to protect it from the elements. That way, if water or condensation gets in the junction box no harm done.
EDIT: just noticed your link to a conduit elbow was for an inside corner, if this is so, then use this
LR conduit body.