Canon vs Olympus for wildlife photography

There are lots of videos on YouTube and web articles on the merits or otherwise of the new Olympus OM-D E-M1 III with the PRO 300mm lens for wildlife photography. None of these really give me the information to tell me how good they are in compared to my existing Canon EOS 5D IV gear so I thought I’d do a ‘real world’ practical non-scientific comparison of various setups.

Quick conclusion – if you want a lightweight solution with a long telephoto then the Olympus gear wins out, particularly with the excellent image stabilisation it offers. If image quality is your primary concern then the the Canon full frame body and lenses are better every time, but at a higher financial cost and substantially greater weight. Olympus micro four-thirds provides a great set of lightweight tools for the kit bag of the travelling birder, but I don’t understand why professional wildlife photographers would be wanting to swap from their SLR equipment.

All images from RAW files and adjusted for exposure in Adobe Lightroom but not sharpened or otherwise ‘improved’.

Original picture (sized to 1800px) @ ISO400

Olympus OM-D E-M1 III + 300mm f4
Olympus OM-D E-M1 III + 300mm f4 + 1.4x (420mm)
Canon EOS 5D IV + 100-400mm f4-5.6 II
Canon EOS 5D IV + 300mm f2.8 + 1.4x (equiv. 420mm)
Canon EOS 5D IV + 500mm f4 (equiv. 500mm)
Canon EOS 5D IV + 500mm f4 + 1.4x (equiv. 700mm)

Cropped 1cm square sized to 1800mm

Olympus OM-D E-M1 III + 300mm f4
Olympus OM-D E-M1 III + 300mm f4 + 1.4x
Canon EOS 5D IV + 100-400mm f4-5.6 II (equiv. 400mm)
Canon EOS 5D IV + 300mm f2.8 + 1.4x
Canon EOS 5D IV + 500mm f4 (equiv. 500mm)
Canon EOS 5D IV + 500mm f4 + 1.4x


  • Canon colour definition better than Olympus.
  • Canon 5D IV + 500mm (with or without teleconverter) better detail resolution than 5D IV + 300mm. There is very slight colour-fringing with the 1.4x converter which should be removed with one click in Lightroom.
  • 5D IV + 300mm + 1.4x better detail resolution than Olympus OM-D E-M1 III + 300mm (with or without teleconverter).
  • Image quality of the Canon + 100-400mm is better than Olympus + 300mm until you need to extrapolate increase image size (as in the image above). So where a large telephoto is required Olympus wins, where the 400mm of the Canon is adequate the 100-400mm wins, and the full frame 5D will always give a cleaner image. Both the Canon 100-400mm and Olympus 300mm have a very good close focus making them useful for ‘macro’ shots (butterflies, dragonflies, etc.)
  • The Olympus + 300mm is much lighter than the other Canon combinations. Only the use of the 100-400mm comes close (and has inferior image stabilisation). The Canon with the 300mm + 1.4 does give a better quality image but is twice the weight of the Olympus rig and more than twice the price.
  • Note: This assessment was based on photographs taken at ISO400. With the benefits associated with full frame sensors it would be expected that the image quality would tend more in favour of Canon at higher ISO settings.
IS (stops)7.57.543-4*33-4*33-4*3
Weight (g)*1211322152687423352785505
*1 Note the additional weight of a tripod is required when using the 500mm lens.
*2 rating based on comparison of images normalised at 1800px images. Where extrapolation is not required the Canon 5D IV + 100-400mm lens jumps from 6th to 4th in the list.
*3 I think the Mk I versions of these lenses only had 3 stop IS, current version has 4 stop.