Given that the effective focal length on APS-C format Fujifilm X and Sony E is a monstrous 1,350mm (1,440mm for Canon M system cameras), you’ll need a shutter speed of around 1/1500th of a second and preferably more, for a decent hit rate in handheld shooting. Both of these can be deal-breakers if you’re after a super-tele lens for shooting anything other than static subjects. It’s also reasonably compact for stowage, thanks to a retractable design.Īs a fully manual lens, the Tokina has neither autofocus nor optical stabilization. And the Canon is full-frame compatible rather than being limited to APS-C crop sensor cameras, as well as sporting super-fast autofocus and highly effective optical image stabilization. That said, the Canon RF 800mm f/11 IS STM is a regular lens with the same fixed aperture rating and weighs in at a modest 1,206g, less than double the Tokina’s 725g. As such, this Tokina is relatively tiny and only a fraction of the weight and cost of most conventional super-telephoto lenses. So why would a lens designer want to mess about with mirrors? The short answer is that by twice ‘folding’ the image in on itself, the size and weight of the complete lens can be dramatically reduced, along with the cost of manufacturing it. The design always carries the risk that image quality will lose something in the translation along the way. As such, light enters through a ring around the circumference of the lens at the front, is bounced back by a curved mirror at the rear, and then focused onto the camera’s image sensor by an additional mirror positioned front and center. As with other reflex lenses, it uses curved mirrors in conjunction with clear glass elements to bounce light backwards and forwards within the barrel. Literally holding up a mirror to subject matter, Tokina’s new ‘PRO’ reflex lenses follow a fairly archaic principle. Tokina SZ 900mmPRO Reflex F11 MF CF at Amazon for $499.Lens construction: 7 elements in 7 groupsĪngle of view: 1.8 degrees (1.7 degrees Canon) (Image credit: Matthew Richards) Specifications Shown here on the right, the 900mm is noticeably larger than Tokina’s 600mm reflex lens and dwarfs the 300mm, but it’s still pretty lightweight at 725g.
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