[ausastronomer (John Bambury)]

Here is a picture of the 80A and the 82A filters. They are both described as light blue but as you can see the 82A (on the right) is a lot lighter than the 80A. As to them both having 30% light transmission ? Rubbish !!!!

Both of these filters are 2" (48mm threads) Hoya filters. These are made in Japan and at the top end in terms of quality.