I am planning to get new canon telephoto lens from Calumet photo and I have been their customer for many years and spend great amount money buying cameras, lenses, light system in the past, I called 800 225 8638 this morning spoke to sales rep. name Kevin, I am trying to find out some information before place my order online, he said " I am not going to provide you free education!! go somewhere else if you are not going to buy something from me today" I am very disappointed after being a loyal customer of calumet for many years... I will not going back again!!