Worth a careful try. Nothing better than convincing yourself. The prerequisite is that you have a good backup. Possibly your PC still can function as such.
Delete a few pics from Finder and see if they still are in iPhoto. If yes, delete a few more. If stell yes, cross your fingers and delete all. If some are totally disappearing, just get them again from your PC.
Speaking of backup: it seems vitally important that you know how to backup the contents of iPhoto. And how to restore them. And even how to restore them on a PC. Suppose your Mac suddenly breaks down and all you have is a backup you can't read on anything else, because it needs iPhoto. You wouldn't like that, would you?
Kees
So I recently got a macbook pro and transferred all my pictures from my pc to my mac. On the pc, it organizes all my pictures into separate folders in the pictures folder in windows explorer. Now on my mac, I just copied over those folders into the pictures folder in finder. Then I imported them into iPhoto. I have a large picture library, at least 40-45 GBs but my mac is saying I have like double that! (and I have to be frugal with my HD space because I only have the 256 SSD) Is it showing such a large number because they pictures are both in iPhoto AND the folders in the pictures folder? If so, can i just delete the folders in Finder since the pictures are in iPhoto?

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