Canon RF 15-30mm f/4.5-6.3 IS STM Lens Review & Results

By Jean Rydberg

If you’re looking for an inexpensive and all-around shooter, the Canon RF 15-30mm F/4.5-6.3 IS STM wide angle zoom may be right for you.

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/100 • f/7.1 • ISO 100 © Ikelite Underwater Systems

Image Quality & Autofocus

When we refer to wide angle in underwater photography, we’re generally including anything wider than 24mm. A wide angle lens is crucial for shooting divers, big animals, landscapes, and wrecks underwater.

This lens has an equivalent focal range of 15-30mm. When used on an APS-C camera like the Canon EOS R7, R10, or R100, the equivalent focal range will be the equivalent of 24-48mm due to the 1.6x crop of the camera’s image sensor. The diagonal field of view of 86 degrees on an APS-C camera or 110 degrees on a full frame camera. This is about 10 degrees wider than Canon’s 18-45mm kit lens which will allow you to get closer to your subject to improve color and clarity in your images.

What’s more is that the overall image is sharper behind a dome port. Compared to the 18-45mm, the RF 15-30mm is significantly sharper edge to edge. 

Canon RF 15-30mm f/4.5-6.3 IS STM Lens © Scott Shew

We also find that autofocus performance is improved over Canon’s kit lens, particularly at the farthest reaches of its zoom range. The 15-30mm complements Canon’s AI-driven autofocus tracking well and we that this lens makes it easy to find and lock focus in situations where the kit lens may struggle.

Some may be put off initially by the maximum aperture range of f/4.5-6.3 though this is typical for a lens in this price category. Fast lenses are not necessary underwater. You’ll want to keep your apertures as small as possible to maximize sharpness across your image- with any wide angle lens we typically recommend f/8 or smaller. 

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/120 • f/16 • ISO 640 © Steve Miller

Who’s It For?

The 15-30mm definitely isn’t the widest option for underwater shooting, but we find that it’s a comfortable range to shoot in the majority of situations we run into underwater. The 30mm end is tight enough to compose great images of smaller subjects like angelfish and turtles.

The wide end can be used for divers, big animals, and even wreck shots. We find that 15mm is a more accessible focal length for the novice wide angle photographer. That’s because you can frame your subject in a pleasing manner from a comfortable working distance. Conversely, with an ultra-wide 10mm rectilinear or fisheye lens you generally need to be within a few inches from your subject to create an impactful image. 

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/125 • f/16 • ISO 460 © Steve Miller

Size & Price

Compared to Canon’s high end L-series lenses like the popular Canon RF 15-35mm F2.8 L IS USM, the 15-30mm is much smaller and lighter. It extends only about 1/4” when zoomed. This is good news when shooting behind a dome port because it means edge sharpness will be consistent throughout the zoom range. The lens is 3” diameter by 3.5” long (76.6 x 88.4 mm) and weighs 13.8 oz (390g).

The RF 15-30mm f/4.5-6.3 retails between $450-550 in the US, making it just a third of the price of Canon’s RF 15-35mm f/2.8L lens.

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/100 • f/9 • ISO 200 © Ikelite Underwater Systems

Summary

The RF 15-30mm f/4.5-6.3 IS STM is an affordable and impactful upgrade for anyone currently shooting an 18-45mm kit lens. The 15-30mm will provide a wider field of view, better edge sharpness, and improved autofocus performance. The extra angle of coverage allows you to get closer to your subject and is a great range for shooting turtles, sharks, reefscapes, and your dive buddy. When zoomed in the lens has a fairly short minimum focus distance and can be used to shoot clownfish, crabs, shrimps, and other smaller critters.

For full frame underwater shooters, the RF 15-30mm is a very capable alternative to the heavier and much more expensive RF 15-35mm f/2.8L. 

Image Gallery 

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/125 • f/13 • ISO 640 © Ikelite Underwater Systems

Canon RF 15-30mm f/4.5-6.3 IS STM Lens © Scott Shew

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/125 • f/13 • ISO 640 © Steve Miller

Canon RF 15-30mm f/4.5-6.3 IS STM Lens © Scott Shew

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/60 • f/5.6 • ISO 100 © Ikelite Underwater Systems

Canon RF 15-30mm f/4.5-6.3 IS STM Lens © Scott Shew

Canon RF 15-30mm f/4.5-6.3 IS STM Lens © Scott Shew

Canon RF 15-30mm f/4.5-6.3 IS STM Lens • 1/200 • f/10 • ISO 640 © Steve Miller

Canon RF 15-30mm f/4.5-6.3 IS STM Lens © Scott Shew

Additional Reading

Close Focus Wide Angle In Depth

Rectilinear vs Fisheye Lenses for Underwater Wide Angle Photography [VIDEO]

Canon RF 15-30mm Installation 200DLM/D Underwater Housings [VIDEO]

How To Get the Best Shots When Shooting Wrecks

How to Find Something to Photograph Underwater

Jean Rydberg is the President & CEO of Ikelite. She has lived her whole life in landlocked Indianapolis, Indiana, but is no stranger to the water as a daughter of Ikelite’s founder Ike Brigham. She has traveled around the world shooting and testing gear and enjoys new challenges in both photography and diving. Jean loves to learn about the creative ways photographers achieve their visions. More than anything she wants to show aspiring underwater photographers that excellence is attainable with any system. When she's not working she's spending time with her husband and two daughters.

Ambassador Steve Miller has been a passionate teacher of underwater photography since 1980. In addition to creating aspirational photos as an ambassador, he leads the Ikelite Photo School, conducts equipment testing, contributes content and photography, represents us at dive shows and events, provides one-on-one photo advice to customers, and participates in product research and development. Steve also works as a Guest Experience Manager for the Wakatobi Dive Resort in Indonesia. In his "free" time he busies himself tweaking his very own Backyard Underwater Photo Studio which he's built for testing equipment and techniques. Read more...

Scott Shew took a 30 year surface interval and dove back into underwater photographer in January of 2024. Scott start shooting in 1991 as a hobby with the Nikonos V and a single strobe but after 4 years of occasional shooting on local dives life got in the way. He recently booked a trip to the Maldives which reignited his passion for underwater photography. Today he shoots the Canon R5 and dual strobes with a renewed excitement. "What a difference 30 years makes!"