Opteka 500Mm1000Mm F8 Manual Telephoto Lens Compatible With Canon Efmount Eos 90D 80D 77D 70D 60D 60Da 1Ds Mark Iii IiThe Opteka 500Mm 1000Mm F8 Manual Focus Preset Lens Is A Classic Refractorstyle Tmount Lens With An Aperture Diaphragm In The Middle Of The Lens Body To Stop Down The Aperture When Necessary However It Is Assumed That Much Of The..