Hello Harry,
Great to hear that you've decided to visit Ireland. There are certainly plenty of interesting and photogenic routes. As 7-days is a not a very long time, could you tell us more about what kind of photography you are interested in and if you prefer urban/nature or coastal/inland?
You could take a look at the
Trip Ideas page to get a feel for the different areas and routes.
The 10 most Instagrammed places in Ireland article could give hints on what other people are finding photo-worthy.
Happy to give more pointers with some additional information.
Cheers,
Lauri