Canon RF100-500mm F4.5-7.1 L IS USM

Where a 400mm lens runs out, 500mm brings a distant train a little closer, and the 100mm end still frames a station scene. Digital Camera World says the focal range gives flexibility when a subject moves closer or further away, which is the situation of every approaching train. The lens has a smooth-to-tight zoom ring adjustment, and the reviewers describe the L-series build and optics as among the best Canon zooms they have tested.

Mount first: this is an RF lens made for full-frame EOS R bodies. It also fits RF-S APS-C bodies with a narrower view, but the same site notes that full-frame RF lenses are usually a size and weight mismatch on small APS-C bodies. It is heavy: the reviewers had noticeable arm and hand ache after 20 minutes handheld on an EOS R, so a monopod suits a long wait at the lineside. The test body matters for tracking. On the EOS R, focusing on birds was hit and miss and the lens felt sluggish next to an EF 100-400mm on a DSLR; on the EOS R5, the reviewers report that autofocus acquired birds instantly and the hit rate rose to practically 100 per cent. Lab charts found excellent centre sharpness through the range, corners that become average at full zoom, and fringing that never becomes distracting. The aperture stays at f/5.6 until about 350mm and closes to f/7.1 at 500mm.

Expert pick · Digital Camera World: Digital Camera World called it a superb L-series super-telephoto zoom with a catch: the fastest autofocus needs an EOS R5 or R6, and autofocus was sluggish on the older EOS R and RP. Read the review

This lens suits photographers with an EOS R5, R6 or similar body who already know they want 500mm and a premium build. It is a weight to carry, so look elsewhere if you travel light, own an older EOS R or RP and expect the fastest tracking, or need a bright aperture at the long end. Canon lists it at about 1,370 g and 207.6 mm long, with a 77 mm filter thread, so plan for a bag that takes a long lens and a strap or monopod for long waits at the lineside.

The Canon RF100-400mm F5.6-8 IS USM gives up reach and aperture for a far lighter, cheaper lens. The Canon RF-S55-210mm F5-7.1 IS STM is a compact lens designed for APS-C bodies (on a full-frame body Canon lists it as usable with an automatic APS-C crop).

Photo: TheFredST / Wikimedia Commons · CC BY-SA 4.0 · source

Canon RF100-400mm F5.6-8 IS USM

Canon · Mid-range

A compact RF-mount 100-400mm telephoto zoom for trains photographed from a platform end or a public lineside vantage point.

Expert pick · Digital Camera World, Nov 2021

Why railfans pick itCheck price on Amazon (affiliate link, opens Amazon in a new tab)

Photo: Henry Söderlund / Wikimedia Commons · CC BY 2.0 · source

Canon RF-S55-210mm F5-7.1 IS STM

Canon · Budget

A very small RF-S telephoto zoom for Canon APS-C mirrorless bodies, giving a field of view equivalent to 88-336mm on full frame.

Expert pick · Digital Camera World, May 2023

Why railfans pick itCheck price on Amazon (affiliate link, opens Amazon in a new tab)