May 16, 2025

Which is better Canon RF 100-400 or RF 100-500 L?

by Cesar

Canon RF 100-400mm vs RF 100-500mm: Budget Powerhouse or Pro Precision

If you’ve read my review of the Canon RF 100-400mm f/5.6-8 IS USM, you already know I’m a fan of that lens for its sharp optics and lightweight versatility. But after spending time with both the 100-400 and Canon’s flagship RF 100-500mm f/4.5-7.1L IS USM on both the EOS R7 and R8, I wanted to take the comparison a step further.

This shootout aims to help you decide which telephoto zoom is right for your needs—and your budget.

Price Breakdown (As of May 2025)

Lens	Current Price	Image Stabilization	Weather Sealing	Weight
RF 100-400mm f/5.6-8 IS USM	$649.99	Yes (5 stops)	No	635g
RF 100-500mm f/4.5-7.1L IS USM	$2,699.99	Yes (up to 6 stops)	Yes	1370g

Build Quality & Handling

There’s no denying the 100-500mm is built like a tank. From its weather sealing to the smooth tension-adjustable zoom ring and tripod collar, everything screams premium. It balances beautifully on the R8, especially with a battery grip or monopod.

The 100-400mm is featherlight by comparison—perfect for all-day handheld shooting, hiking, or travel. Its build is surprisingly solid despite the plastic exterior, and it’s a stealthy, approachable lens that doesn’t draw attention.

Image Quality

Let’s cut to it: both lenses produce sharp, contrasty images, but there are key differences:

The 100-500mm delivers better sharpness wide open and superior edge performance at 400mm and beyond.
The 100-400mm can hold its own through much of the range, especially from 100–300mm, but begins to soften slightly past 350mm, especially on high-res sensors like the R7.

Great blue heron gliding low across a vivid green pond, wings fully extended. — A great blue heron captured in flight over a Florida pond, showcasing the RF 100–400mm’s tracking capabilities paired with Canon R7.

Autofocus & Tracking

Both lenses benefit from Canon’s speedy Nano USM autofocus, but the 100-500mm tracks better in complex bird-in-flight (BIF) scenarios—especially on the R8’s full-frame sensor. I noticed more consistent hit rates in challenging light and cluttered backgrounds.

Still, the 100-400mm performs admirably—especially considering the price.

Anhinga launching from a wooden post with wings outstretched and mouth open. — The moment an anhinga takes flight—snagged with precision using the RF 100–400mm on the EOS R8.

Osprey flying with wings arched and eyes locked forward, against a soft forest background. — A mid-flight osprey captured at 1/2000s with tack-sharp focus on the Canon R7 paired with the RF 100-500 —highlighting the lens’s edge clarity at 500mm also at high ISO in relatively low light ISO 6400 on this shot.

Reach & Versatility

That extra 100mm reach matters, especially if you’re photographing distant wildlife like eagles, owls, or wary waders in Florida wetlands. The 100-500mm gives you more detail and compression, often letting you avoid cropping in post.

That said, for many backyard birders, zoo trips, and travel photography, the 100-400mm delivers more than enough reach in a dramatically smaller, more affordable package.

Alligator partially submerged in calm green water, with head and eyes above the surface. — Florida’s wild lurking below the surface—this gator was photographed with the Canon R7 paired with the RF 100–400mm from a safe distance.

Which Should You Buy?

Choose the RF 100-400mm if:

You’re on a budget and want incredible value
You need a lightweight lens for travel or handheld work
You don’t often shoot in challenging light or at extreme distances

Choose the RF 100-500mm if:

You shoot wildlife or sports seriously and regularly
You want L-series image quality, weather sealing, and low-light confidence
You already own a full-frame Canon mirrorless body

Final Thoughts

The Canon RF 100-400mm is one of the best deals in the entire RF lineup. But when you’ve experienced the extra reach, premium build, and consistent optical performance of the RF 100-500mm, is it hard to go back? Not really the 100-400 is an exceptional lens for a wide variety of situations and its budget price and compact size a light weight make it a perfect lens to carry with you everywhere you go.

I’ve used both lenses extensively on real-world shoots around Central Florida, and I’ll continue using both. The 100-400 is my go-to for spontaneous birding and light travel. It’s what I take with me everywhere I go, my daily driver. The 100-500 comes out when I need every ounce of performance.