I recently bought an Orion (US) violet blocking filter for use on my short
tube 80mm achromat. Not being able to afford an apo, I wanted to see how
this works on bright objects like the moon and Planets. It truely does
reduce the purple fringing found on teh limbs of these objects!

Some can say that there is a very slight yellow cast seen, but it is very
slight, adn actually helps on subjects Like Saturn adn Jupiter. For those
who want better color correction on their refractor but cant spend teh money
for an apo, these filters seem to work well!

Matthew Andrew