Does anyone else think that the boyhood portraits of Wickham and Darcy in the BBC series were too far off?

[Stephen]

I tend to rewatch the BBC series quite a lot but it's always bugged me that the portraits we see when Lizzy is visiting Pemberly look so little like the actors who played the roles.

I recently watched all the "extras" on the deluxe DVD set that I got from the library and they never mentioned them at all. (I was hoping that they'd tell us that the portraits had actually been in the house or something) I was wondering if anyone knew the story behind why they looked so different.