Introduction

On October 15th, 2015 Canon announced the Canon EF-M 15-45, replacing the larger original Canon EF-M 18-55 as the official kit lens of the Canon EOS M system.

Canon had this to say about the EF-M 15-45;

The EF-M 15–45mm f/3.5–6.3 IS STM is a compact, stylish zoom lens for EOS M series digital cameras. A special retraction mechanism shortens the length of the lens to just 1.76 inches (44.5mm) when the camera is off, to help make carrying and storing the lens and camera even easier. The quiet stepping motor (STM) design helps ensure low-noise focusing that’s ideal for recording movies. The 35mm-equivalent 24–72mm range combines a wide angle for landscapes and big group photos, with a telephoto zoom for close-ups and detailed headshots. Carefully designed lens placement and special Canon coatings help keep ghosting and other lens flare from your images.

Specifications

Core Specifications
Lens Type Zoom lens
Format Size APS-C
Focal Length 15-45mm
Image Stablization Yes
CIPA IS rating 3.5 stops
Lens Mount Canon EF-M
Aperture
Max Aperture F3.5-6.3
Min Aperature F22-40
Aperture Ring No
Diaphragm Blades 7
Optics
Elements 10
Groups 9
Focus
Minimum focus 25cm
Maximum magnification .25x
Autofocus Yes
Motor type STM Stepper motor
Full time manual Yes
Focus Method Internal
Distance Scale No
DoF Scale No
Physical
Weight 130g
Diameter 61mm
Length 45mm
Sealing No
Color Graphite or Silver
Zoom Method Rotary (extending)
Power Zoom No
Zoom lock No
Filter Thread 49mm
Hood Supplied No

Design

Exterior

Most likely to keep both the weight and cost low, the EF-M 15-45 is primarily composed of a plastic exterior and also a plastic mount.   Even though it's made of "cheaper" parts, the zoom is smooth.

To make the lens as small as possible, it compacts down to a smaller size than it's operational size.  There is a lock on the side, where a user must move the switch up and twist the lens slightly to move it to it's starting 15mm position.  If an EOS-M camera detects that the lens is in its locked and closed position, the camera will warn the user.

 

Focus

The STM motor used in this lens is a lead screw STM motor and offers fast AF.

The manual focus adjustment is focus by wire, with a small manual focus ring at the end of the lens.  Focus by wire means that electronically the lens detects if you are spinning the focus wheel and moves the lens accordingly.  As you move the wheel faster or slower, will depend on how quickly the focus adjustment occurs.  Many people dislike this focus method because it lacks the tactile feel and consistency that you get with mechanically coupled focus rings.

 

Elements

The EF-M 15-45 contains 10 elements in 9 groupings and no special elements.

Zoom Aperture

The EF-M 15-45 is a relatively slow lens, progressively moving towards its maximum aperture of 6.3. It reaches 6.3 at 40mm and stays at maximum aperture until the end of the zoom at 45mm.

Zoom Aperture Comparison

Comparatively the EF-M 15-45 is the slowest kit lens that Canon has made for the EOS-M system.  While there isn't necessarily that much poorer than the other kit lenses, attempting to make the lens as small as possible has certainly compromised its aperture performance even when compared against its peers.

Color Performance

Summary - MTF

The MTF (or Modulation Transfer Function) provides a way to measure lens performance. Atypically this is computer generated based upon models, the lone exception being Zeiss that shows their MTF’s based upon a production lens sample.

For a detailed explanation of MTF and specifically how Canon shows their charts, refer to the article in Canon’s Digital Learning Center here.

Reading MTF Charts

The MTF charts indicate that that 15mm wide open is the worst performing, with the outer extremities improving as you stop down to F8, with F8 performance being quite good across the zoom range.  Wide open at 45mm is quite good, and excellent as you stop down to F8.

Our copy, like many copies of this lens, didn't match well against the MTF.  This lens has a great deal of sample variation.  This is the second 15-45mm that we have tested, with similar results.  Good copies do exist, however, I have yet to get my hands on one.

 

 

Samples

Our sample is decentered with the left side being the worst. At 15mm the corners are a hot mess with a combination of heavy vignetting and low resolution turning them into soup.  Center performance is quite good throughout the focal range.  Our copy struggles mightily in the corners across all focal lengths and generally is at it's best at F/8.  Using F/8 lowers your overall resolution because of diffraction however you can mitigate that somewhat by using DLO.

If you are not prone to pixel peeping the results, the lens is mostly perfect adequate for a walk around lens stopped down one stop from wide open.  For critical results in the corners, either have an amazing copy of this lens or stop it down significantly.

Canon’s DPP and some of Canon’s later camera bodies contain DLO, Digital Lens Optimizer, which can be used to correct various aberrations with any of the supported cameras and lens combinations.  All the EF-M lenses have DLO “configurations” allowing you to further improve the characteristics of the lens.  Using DLO with this EOS-M lens is highly recommended as it clears up a lot of aberrations and the resultant images are excellent.  As you can see from our DLO samples below it sharpens up this lens and removes all traces of CA especially at 15mm.

If you are interested in learning more about DLO, Canon has a DLO mini-website, located at https://global.canon/en/imaging/dlo/

Sharpening for non DLO images is set at USM Strength 2 Fineness 2 and Threshold 1 and for DLO images, USM Strength 1 Fineness 2 Threshold 1 with DLO strength set to 50.

 mm  F stop 

Center

Bottom Left Corner

Filename EF-M15-45-HOT-15-35.jpg
ISO 100
Shutter Speed 1/1250
Aperture f3.5

Infrared Performance

Summary

We tested this lens on a full spectrum modified Canon M5.  The conversion was done by Kolari Vision, who in our opinion, one of the leading vendors of infrared modified cameras and filters.

Converting your camera allows it to be more sensitive to infrared wavelengths, that are normally reduced by your sensor’s IR/UV cut filter.  IR conversion removes that cut filter, and replaces it with an infrared filter, or in the case of full spectrum, clear glass.  This allows the camera to be far more sensitive to various wavelengths that normally a camera is not.  Because normally cameras are not sensitive to these wavelengths, lenses are also not designed around these wavelengths.  Various problems may occur with complex lens designs, including hotspots (a center area of the lens brighter than the peripheral, more noticeable as you stop down the lens) and wavelength smearing which atypically shows up as a loss of resolution in the periphery of the lens.  Lenses are also more prone to flare.

Each test is performed using Kolari Vision slim PRO anti-reflective infrared filters, which we find to show the best characteristics and contrast of any filters we have tried.  They also have Teflon coated filter threads which we find to be extremely useful when we are swapping filters frequently during testing.  While any filters will show an adequate final image, since each photo you are taking with a converted camera has a filter, we recommend using the highest of quality filters that you can afford.

Hot Spot Performance

This lens exhibits slight hotspot behavior at F16-22, however, it's pretty minimal and nothing to really worry about unless you shoot consistently at the smaller apertures.

 

 mm  F stop 

Samples

This lens exhibits some smearing at 15mm for infrared photography, but generally outside of that delivers adequate results.

Center resolution, as with color is excellent, and also the same as with color, your best results are when you stop down to around F/8.

Sharpening is set to an aggressive USM Strength 6 fineness 6 threshold 2 for non-DLO images and set to USM Strength 4 fineness 5 threshold 2 with DLO images, with DLO strength set to 100.

 

 nm   mm  F stop 

Center

Bottom Left Corner

Filename EF-M15-45-590-15-35.jpg
ISO 100
Shutter Speed 1/1000
Aperture f3.5

Vignetting

Vignetting is quite high at 15mm, typical given its small size of a lens.  Vignetting continues to be high until after 24mm, or until you stop down the lens considerably.

While vignetting is correctable to this extent; in the corners, it does lower the dynamic range and increases noise.

 

 mm  F stop 

Conclusion

This lens is a mixed performer.  If you win the lottery and have one of the pink unicorn versions of this lens, then hold onto it and never let it go.  If you are a mere mortal like the rest of us, be prepared to stop down this lens a lot to get any reasonable performance out of it.

 

EOS Mirrorless Reviews is not affiliated with Canon Inc. or any of their subsidiaries.