(Here are the three most basic things you need to know to get you started. 1) You must focus the lens manually by turning the lens focus barrel. 2) You must set the focal range (420mm, 600mm, 800mm, etc.) manually by sliding the lens focus barrel to the desired range.
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Viltrox EF-E5 Sony E Lens Adapter Auto Focus Full Frame 0.71x Speed Booster for Canon EF Lens to A1 A7C A7R IV A7iii A6400 A6600
Aliexpress UK
Ultra Multi Coating: Adopts multi-coated technology to reduce flare and ghost to get vivid color and clear images. Premium optical glass lens provides high light transmittance. Universal 1/4 Mounting: The base with 1/4 screw thread down the lens makes wide application on tripod and monopod, the base with can rotate, convenient to install in seconds.
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K&F Concept EF to EOS R Adapter Auto Focus Lens Mount Adapter for Canon EF EF-S Lens to Canon EOS R/RF R3 R6 R50 Mount Cameras
Aliexpress UK
This includes Canon EOS 1D, 5D, 7D, 10D, 20D, 30D, 40D, 50D, 60D, 70D, 80D, 90D. all the way to EOS 4000D. For sale is a Canon EF fit Lightdow 420-800mm lens. The item you receive will be new.
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EF-EOS R Lens Adapter Electronic Auto-Focus EF to R Mount Adapter for Canon EF/EF-S Lens to EOS R Series Mirrorless Cameras
Aliexpress UK
EOS 100D Rebel SL1. EOS 400D Digital Rebel XTi. The incredible 420-800mm focal range gives extraordinary "reach" and allows you to zoom in on distant subjects that normal lenses just can't get close to.
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Auto Focus Camera Lens Adapter with Drop In Variable ND Filter ND3-ND500 Lens Converter Ring for Canon EF/EF-S Lens To EOS R RP
Aliexpress UK
Although lens is fully manual if you set your Canon DSLR to AV mode, exposure will be automatic.
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For Canon EF / EF-S Cap Set Rear Lens Cap + Camera Body Lens Cap for Canon EOS EF mount With Canon Logo / Without Canon Logo
Aliexpress UK
(It also has an adjustable tripod mount for image stability. Mount: Canon EF. Here are the three most basic things you need to know to get you started. 1) You must focus the lens manually using the lens focus barrel.
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Viltrox EF-EOS M Autofocus Lens Electronic Adapter Ring For Adapting Canon Lenses EF/EF-S to EOS M EF-M Cameras M2 M3 M5 M6 M10
Aliexpress UK
Although lens is fully manual if you set your Canon DSLR to AV mode, exposure will be automatic.
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Lightdow 420-800mm f/8.3-16 Manual Telephoto Zoom Lens for Canon RF Canon EF Nikon F Nikon Z Sony A Sony E Mount Camera
Aliexpress UK
The incredible 420 to 800mm focal range gives extraordinary "reach" and allows you to zoom in on distant subjects that normal lenses just can't get close to. I have personally used this lens on my Canon 80d, a Sony A6300 and a Panasonic G6 and GH5!
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Canon EF-S 55-250mm f/4-5.6 IS II Lens
Aliexpress UK