Well, my intention When I bought this filter what to have a diferent look from my 720mm infrared filter (same brand). But it does not work with my A65 or with a friend of mine's A77. No matter how long the exposure, the image which almost black. No mention about that in the product description. So I returned the item.
Be aware thatthis filter will not work with all cameras and the only way to find out if it will work with yours is AFTER you get your hands on it and make a real test. Do not assume That where a 720mm works this filter will work too, cause cameras have diferent wavelentghs sensibilities.