I'm assuming that you are querying tags to find the images? I did notice a image that shows up under "Kodak Gold 200", but when you visit the flickr page it is clearly "Kodak Colorplus 200" (yes apparently they are different film stocks.) Unfortunately there is limited consistency in tagging film stocks.
Yes, that's right. The querying based on tags has its limitations considering the consistency. Some people even post b/w pictures and take color films. I have currently not found a better way to query it but I will def think about it.