AllSync & AllDup

I am a new user of AllDup, and I have a basic question regarding the settings to use to find similar photos in different source folders.

In Folder A, I have several photos, and no subfolders.

In Folder B, I have many photos, grouped in several subfolders. I know there are photos similar to each other in any of the subfolders in Folder B.

I would like to use AllDup to compare the photos in Folder A against the photos in all the subfolders of Folder B. I do not want to search for similar photos between and among the subfolders in Folder B. So far, the only way that I have been able to do this is to check Folder A as a one source folder, and each subfolder in Folder B as a second source folder, run the search, and then repeat the process separately for each subfolder in Folder B. This is very tedious.

Is there a more efficient way to do this?

The settings I am using are:
Comparison Method: Compare only files between different source folders
Search Method: Find similar pictures (using dHash)

Thanks.

There is no other way to do this.

Are A & B in the same directory tree?

/pics/A
/pics/B
/pics/B/1/
/pics/B/2/
/pics/B/3/

If that's the case, simply move A outside of /pics/ [temporarily] then it should work (with Compare only files between different source folders).

move /pics/A /outside/A

With that, you'll then have:

/outside/A
/pics/B
/pics/B/1/
/pics/B/2/
/pics/B/3/

& that should work, no?

Thank you very much for your very quick reply, and for your detailed suggestion. I will try it.

Thanks again.