This expensive filter has been abused and neglected for the last 20 years. I just did like the way it dimed stars.
Its strength is in showing Faint Nebulae.
I have no doubt that the filter is useful, but after cleaning it twice, it still looked somewhat dirty, if though it still needed a clean. Not terrible, but nevertheless, this is not a buy for the purist that want items to be in prime condition.
Priced accordingly:
$50 posted anywhere in Oz.
PS: Sorry for the reflection of my smart phone at the top of the filter.