A while back I bought a set of filters. The filters are from some place in Eastern Europe but the main reason for buying them were the two step up rings [40.5 and 52] that I just happened to need. The filters worked just fine and I guess are of reasonable quality. They've been mostly used with the 35mm camera's meter so I didn't really worry too much with exposure. On the camera with the broken meter I just used the filter factor that's on the filters. Everything worked fine so I didn't worry.
Well today I decided to check the filters with the meter to see if the filter factors actually match. At first the numbers seemed way out of wack. Then I noticed I was holding them wrong way out. Flipping them over the numbers matched up nicely. I then checked some Hoyas [Are these made in Georgetown?-)] and they also did the same thing. Is this normal? Is this just one more case that I shouldn't check things to avoid confusing my self? Or does this mean the quality of the filter is lacking?