Having just tried this, it appears that all this does is put the Session in the same directory as the original photo. It still creates a Session with the Session's database and the Session's related folders, including a copy of the original image. When I did some basic edits, I wound up with a very large directory side by side the original photo. If that's correct, this is a distinction without a difference. I also read a thread in which Capture One representative David Grover effectively says that there is in fact no way to get around this. Capture One requires either a Catalogue or a Session, there being no substantive difference between them for the purpose of this discussion.
If I'm missing something, I'd be delighted to know what.
That isn't how it works for me.
As I said it does add a Capture One folder to the same folder as the raw, but this isn't the session folder, it just holds the preview and edit information for the edits for raw files in that folder (this information needs to be stored somewhere).
And it does still creates a Session folder (wherever you told it to set up the session) but this just holds information related to the session management, it doesn't add a copy of the original raw, nor does it store the preview, so it remains very small. I keep the session on my SSD that holds the OS, but all my raws are on an external HDD
My "C1_viewer" session folder is still very small (compared to my proper session folders) even though it has been used to view and edit thousands of images.
I'm not sure what to advise, as I've given the same instructions to many people across several forums and the feedback has always been that its worked. No one has ever come back to say it didn't work as described, so I'm struggling to think of what might be wrong.
When you open a file from the system folder in C1, there shouldn't be any files added to the Capture folder, but it seems from what you are saying, the raw files are still being copied into the C1 session. Is that correct? It definitely doesn't happen with me.
You are sure you are opening the files from the C1 system folders directory, there shouldn't be any opportunity to copy the raw into the session, it should just open from its original position.
But, as I said I'm puzzled as to what might be happening.
As an aside I got this method from a David Grover video years ago, and have used it ever since, together with standard sessions when I want to keep raw files within the session.
Sorry,
Graham