Replying to How bad is bad enough?

I just got some new skis, went out riding and realized that i have a few scratches on my base. Now I've gotten scratches before but not cared because they were older skis etc. But with my new pair i want to preserve them as long as possible. So i know scratches are bad for you base but how do you distinguish a deep scratch from shallow one. Is there a certain depth that you should go to a ski shop and get them fixed? Any help for me being a newby would be greatly appreciated !