Thanks for the suggestion.
The link below will connect you to a lot of material that I have provided on my YouTube channel.
The Spherical projection, or any equirectangular image is based on some simple procedurals and quality rules. I hope my series will support your efforts.
The combination of images with 3D and compositing (as in Ae, Fusion or NUKE, etc) is based on images that have more a reproduction quality than an artistic direction—if not art directed from the start for a specific project.
I have discussed different storage formats as well. My suggestion, create your own material, based on a precise pipeline and with material you know, which condition they were produced.
The key is often just to find a middle ground object as seam, between fore and background. This can be fences, plants, buildings and other objets given naturally in architectural visualization, and those elements are more often than not a nice connection between a 3D model and the spherical “panorama”.
In the Cineversity J.E.T. series, I have discussed a lot of those options as well, as the spherical work only to a certain degree, and camera projection of just images need to be understood for each project and where to place them, e.g., based on parallax or the distance to it where it doesn’t count so much anymore.
If you have any questions - please start a new thread in the Q&A forum. If possible provide a sketch of the target scene, so I can share what ever is possible for me. (I have thought such stuff way over a decade ago and use it over two decades by now.
In the Cineversity “Integration” series, I have discussed ten main areas for compositing of practical and CG based content. All there source that I have named are based on practical projects or experience thereof and most of them got awards or were at least an “Official Selection” on International Film Festivals. Being as well an architect, I certainly know what is needed for the projects in question.
My best wishes and enjoy the “Photography for 3D Artists” series.