Is it possible to have 2 different backup systems for different external hard drives? 1) I want to plug in an external hard drive and then download all of the photographs that I take in RAW format on my Canon 7D camera onto this external hard drive, and then backup these photos onto a second external hard drive. These photos would NOT be held on my MacBook Pro. 
2) I then want to backup everything on my MacBook Pro to an external hard drive (but NOT the same external hard drive as the one the RAW photos will be held on).

So is it possible please to set up these two different systems? At the moment I use Time Machine to backup everything on my MacBook Pro - but I need to have two  different systems as I outlined above- can Time machine be setup for this or is there a different way to do it? Any help would be gratefully received. Thanks
Yes, Time Machine can do this. All you need to do is connect at least two hard drives to your Mac. One hard drive will be for you to download your raw photos on to manually as you wish. The other hard drive will be your TM hard drive. Because your first HD for your photos is connected to your Mac, it wil also be backed up whenever TM does a backup. Those TM backups will backup what's on your Mac and what's on your photos HD, but you also have the option to select anything you want to exclude from the backup by going into the Options on TM.