Hi, there! How trustworthy are perforation gauge apps? I was organizing some stamps and decided to use one of these softwares. At one point, the app indicated that a 1c Franklin had a 11,5x10,5. So I've checked the values and they were rounded up. According to the software the unrounded perf was 11,36x10,5. Again I've compared it to a perforation gauge I have and it did fit better 11,5 not completely but better than 11.
Now how do you solve that? What can you tell me? How would you classify it? Comments welcomed!