Facebook Pixel dPS Writer’s Favorite Lens - the Canon 100-400mm f/4.5-5.6 L-Series Lens

dPS Writer’s Favorite Lens – the Canon 100-400mm f/4.5-5.6 L-Series Lens

Last August I bought the Canon 100-400mm f/4.5-5.6L IS II USM L-series lens for myself as a birthday gift. Since then it’s been in almost constant use as I’ve photographed horses and wildlife in Arizona, Florida, Georgia, Illinois, Nevada, and Utah. I’ve made more than 14,000 images with it in the last five months! Read on to learn more about why I love this lens so much.

Favorite Lens Canon 100-400mm

Salt River wild horse yearling with ferns – 5D Mark III, Canon 100-400mm @ 248mm, 1/350th, f/5.6, ISO 8000.

Canon 100-400mm f/4.5-5.6L IS II USM technical specs:

  • Focal Length: 100-400mm
  • Maximum Aperture: f/4.5-5.6, variable
  • Minimum Focusing Distance: 3.2 feet (0.98m)
  • Zoom: Rotation
  • Filter Size: 77mm
  • Weight: 3.62 pounds (1.64kg)
  • Price: $2,049.00 USD (at the time of writing this article)

Compared to the Canon 200-400mm

Compared to other lenses of similar focal length the Canon 100-400mm is a bargain, especially since there’s no sacrifice to image quality. Compare it to the Canon flagship telephoto lens, the 200-400mm f/4 which is a whopping $10,999. The 100-400mm lens is a moderate $2,049. Of course, the 100-400mm is one to two stops slower than the 200-400mm but for an $8,800 price reduction, I can handle the loss. I think you probably can too.

Favorite Lens Canon 100-400mm

Salt River wild horse with bird, monochrome – Canon 5D Mark III, 100-400mm lens @ 400mm, 1/1000th, f/8, ISO 500.

Those of you who know long lenses also know that the 200-400mm has a built-in 1.4x extender. Sold separately, those are about $500 so if you invest in one (and you should) your savings between the two lenses is now $8,300. In other words, you still save a small fortune by shooting with the 100-400mm lens instead of the 200-400mm.

Lastly, the 200-400mm weighs in at almost 8 pounds (3.63 kg). By shooting with the 100-400mm, you also save your back, neck, hands, and shoulders from a lot of wear and tear. I personally can’t hand hold an 8-pound lens, which means to use the 200-400mm I’d also have to carry a heavy monopod with a gimbal head. My always-aching upper body thanked me for buying the 100-400mm instead.

Favorite Lens Canon 100-400mm

Peeking Salt River wild foal – Canon 5D Mark III, 100-400mm lens @ 340mm, 1/350th, f/8, ISO 500.

Practical size

For a telephoto lens of its focal length, the 100-400mm is a relatively compact, hand-holdable, and practical lens. I can attach it to my Canon 7DII or Canon 5DIII camera bodies and shoot with it all day long without using a monopod or tripod. The combination with either camera weighs in at about 6 pounds (2.72 kg). Note that that’s a whole 2 pounds (907g) less than just the weight alone of the 200-400mm lens. It’s a lot of focal length, in a fairly small package.

Favorite Lens Canon 100-400mm

Splashing Salt River wild stallion, monochrome – Canon 5D Mark III, 100-400mm lens @ 278mm, 1/750th, f/6.7, ISO 500.

The 100-400mm lens also easily fits into my Kata backpack (now manufactured by Manfrotto). When I pack for an equine and wildlife photography trip, I cram the 100-400mm, 70-200mm, 24-105mm, extender, both my camera bodies, laptop, hard drives and a slew of accessories into this bag. Yes, it’s a great bag and holds a lot for its size but the point is, the 100-400mm fits in it. Larger lenses like the 200-400mm would not.

The 100-400mm is on the left; accessories like batteries, cards, and a rocket blower fit in the same divider, tucked in at the top of the bag. 7DII is in the middle with 24-105mm attached, the open divider is for the 5DIII camera body (which I used to take the pic). 70-200mm lens is on the right; 1.4x extender fits in the same divider in its own little case, tucked in at the top of the bag.

Same arrangement, top view.

Bag zips!

Features of the Mark II version

If you’ve shot with the original 100-400mm lens, the Mark II has some great new features and I’d recommend upgrading. The original was more of a pumping action when you extended it. The Mark II extends with a twisting action. Twisting to extend is faster and easier to use than the original mechanism. There’s also a ring that you can tighten or loosen, increasing or decreasing the torque on the twisting mechanism. In other words, if you want to rapidly zoom in and out, you loosen the ring to reduce the torque. If you want to keep the lens zoomed at a specific focal length, or locked into its most compact position, you can tighten the ring and increase the torque.

It’s a very intuitive motion. As you use the lens, you’ll find your hand easily moves from the rubber grip used to adjust the focus to the grip used to extend the focal length and to the adjustment ring.

Favorite Lens Canon 100-400mm

Cumberland Island wild horse in the live oak shadows, monochrome – Canon 5D Mark III, 100-400mm lens @ 400mm, 1/350th, f/9.5, ISO 320.

Built to last

The Canon 100-400mm lens is also built to last. The metal, weather-sealed build is why I always invest in original, L-series Canon lenses. I trip, I fall, I drop things. It’s just part of who I am. When I invest in a lens that I plan to use all the time, it can’t be a fragile little thing that needs to be babied. It has to be able to withstand my clumsiness plus dusty, desert winds, and driving snowstorms.

Favorite Lens Canon 100-400mm

Antelope Valley wild horse snuggles – Canon 7D Mark II, 100-400mm lens with 1.4x III extender @ 560mm, 1/200th, f/8, ISO 200.

Just a few weeks ago I was shooting in very snowy, wet, conditions in Nevada. When I made it back to the car, I was soaked. My camera and lens were also dripping with melting snow. I toweled everything off and had a moment of panic when the inside of the lens fogged just a tiny bit. Happily, 15 minutes later, the slight condensation dissipated. If the lens hadn’t had such excellent weather sealing, that snow storm might have ended my shoot. A lens with a cheaper build may have been out of commission for days.

Favorite Lens Canon 100-400mm

Wild horse blizzard in Antelope Valley – Canon 7D Mark II, 100-400 @ 400mm, 1/250th, f/9, ISO 800.

Superfast autofocus

This lens focuses quickly, especially on my 7DII. I rarely miss a fleeting moment. I’ve actually captured images other people in my group are surprised to see. I credit that both to the fast focusing ability and the maneuverability of the 100-400mm lens.

Favorite Lens Canon 100-400mm

Antelope Valley wild horses snow globe – Canon 7D Mark II, 100-400mm with 1.4x III extender @ 560mm, 1/4000th, f/8, ISO 1000.

On occasion, I do have trouble focusing due to low contrast. Let’s face it, that happens to all of us. With this lens, I pull back a bit to 200mm or 300mm, grab the manual focus ring and dial in until I start to feel like I have an edge. Once I do, I use back-button focus to lock in sharpness. Once I’m focused, I zoom back to 400mm. The focus holds through this transition and I grab the shot. It’s quick and magical. None of the other long lenses I’ve used have quite the same intuitive feel for focusing.

Favorite Lens Canon 100-400mm

Antelope Valley winter white wild stallion – Canon 7D Mark II, 100-400 @ 400mm, 1/4000th, f/5.6, ISO 500.


One of my favorite aspects of this lens is its flexibility. I use all focal lengths and apertures of this lens without hesitation. For a standard 100-400mm, I attach it to my full frame 5DIII. For a little extra reach, I attach it to my crop sensor 7DII.

On a crop sensor, the effective focal length of the 100-400mm increases to 160-640mm (1.6x). If I need even more reach, I add the Canon 1.4x Extender and the effective focal length on my 7DII increases to 224-896mm. The extender also increases the total weight by about 8 ounces, but I don’t even notice it.

Note: For Canon crop sensor cameras, multiply the focal length by the 1.6x crop factor to determine the effective focal length. Read more here: Crop Factor Explained.

With the Canon 1.4x Extender

Favorite Lens Canon 100-400mm

Antelope Valley band of wild horses running in the snow – Canon 7D Mark II, 100-400mm with 1.4x III extender @ 560mm, 1/1000th, f/8, ISO 1000.

I love using an extender with this lens. At 400mm, the minimum aperture is f/8, which is my preferred wildlife setting anyway. Autofocus is still blazing fast, although it is limited to the center focus point when the extender is attached. I haven’t seen a significant loss of quality or sharpness with the extender. Since I can still handhold this combination, even if there was a slight loss, I’d be more than okay with it. A slight loss of sharpness is always preferred (in my book at least) to missing a shot because you were fiddling with your tripod or just didn’t have the reach you needed.

Note: Read more about extenders here: The Pros and Cons of Using Teleconverters (Extenders) on your DSLR.


Favorite Lens Canon 100-400mm

Salt River stallion and son eating eel grass in the river – Canon 5D Mark III, 100-400mm @ 400mm, f/9.5, 1/125th, ISO 320.

My job as a photographer is to put myself in the right place at the right time, to find the beauty once I’ve put myself in that place, and to understand the light and compose my image. My gear gives me the technical boost I need to pull all that off.

I’m going to be honest here, I’ve rarely shot with third-party lenses. I can’t compare Canon lens IS (Image Stabilization) to other brands. But, what I can tell you is that when I find myself shooting at 400mm with a 1.4 extender at a relatively slow shutter speed of 1/250th, it’s not my steady hands ensuring that my shot is in focus – it’s Canon’s. Their IS in this lens is like a super power. It is exactly the technical boost I need to make the images I want to make.

Even works for panoramas

Favorite Lens Canon 100-400mm

Ely County Nevada Open Range, panorama – Canon 7D Mark II, 100-400mm @ 100, 1/320th, f/11, ISO 250.

I’ve even used this lens to create panoramas – handheld, no less. If I’m using the 100-400mm and I see a gorgeous vista, I set the lens to 100mm. I create a very secure hold by pressing together my elbows and locking them into my chest. Then I slowly click my way through the scene. Lightroom or Photoshop both do an amazing job of stitching and correcting perspective issues. If you’re a landscape photographer you might be horrified at this method but if you’re a wildlife photographer, it’s truly another practical tool in your photographic arsenal.

Image quality

Favorite Lens Canon 100-400mm

Salt River wild mare silhouette at sunset – Canon 5D Mark III, 100-400mm lens @ 400mm, 1/8000th, f/11, ISO 600.

With all this technical talk, you might be wondering why I haven’t said all that much about image quality. I’ve included over a dozen images here and I hope that speaks for itself. Details render crisply. I haven’t discovered any artifacts or unusual aberration in any of the 14,000+ images I’ve shot with this lens.

In wildlife images, I prefer a creamy blurred background rather than a bubbly bokeh background since I find that big, bokeh circles detract from my subject. This lens renders the sort of backgrounds that I prefer.

Favorite Lens Canon 100-400mm

Backlit Cumberland Island wild horse at sunset – Canon 5D Mark III, 100-400mm lens @ 100mm, 1/500th, f/4.5, ISO 2000.

Shooting into the sun for a backlit image produces just the right amount of lens flair. Shooting with the sun at my back or off to my side produces just the right amount of contrast. With bright overcast skies, the lens still shapes the light beautifully.

The Canon 100-400mm lens renders color in a very neutral way. While it’s fun that some lenses render brighter or more vivid colors, I prefer to have a more neutral starting point when I begin to edit my RAW images.

Over to you

In all, this is the absolute best birthday gift I’ve ever given myself. I even wish I’d bought it before I upgraded my 70-200mm.

What about you? Have you used either the original or Mark II version of the Canon 100-400mm lens? Or do you have another favorite telephoto zoom lens? Share your feedback on your favorite lens with the dPS community in the comments below.

Shop for the Canon 100-400mm lens here:

Favorite Lens Canon 100-400mm

Mom!! – Canon 7D Mark II, 100-400mm lens with 1.4x III extender @ 560mm, 1/1250th, f/8 ISO 800.

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Lara Joy Brynildssen
Lara Joy Brynildssen

is an avid equine, wildlife, nature and travel photographer. She is crazy about her cats, loves her Canon 5D Mark IV, and never refuses a sip of limoncello. More seriously, LJ is working on several series of wild horse images, writes about and teaches photography and exhibits her work in the Chicagoland area. Follow her at www.LaraJoy.us.

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