Poke around my website and you'll find only a few images from mirrorless cameras. And yet I've been shooting mirrorless Olympus and Panasonic Micro 4/3 since 2011. They served as my point 'n shoot cameras and portability was the main attraction. DSLRs ruled my landscape, stage travel and video work, but snaps at the pub or along the road to work were the domain of my mirrorless cameras.
Micro 4/3 ergonomics and image quality fell short for me so I switched to an EOS SL1 as my light kit. The SL1 was refreshingly fast and easy to use, but with EOS M3 prices in free-fall due to the M5 and M6, I snagged a M3 kit with EF-M 18-55 3.5-5.6 IS STM and EVF-DC1 viewfinder. It's similar in size to an Olympus Pen but more intuitive and ergonomic. Is it as easy to use as the diminutive SL1? No, but it's smaller!
The M3 is tiny: barely larger than a Canon S100 point 'n shoot. With an EF-M 22 2.0 STM pancake lens, it squeezes in a pant pocket. Okay, not skinny jeans, but an easy carry in a purse or coat pocket. Needless to say, the M3 is probably not a good choice for those with large hands.
This petite Japan made camera feels like quality: magnesium body, matte black paint, and contoured grip. It's a slim 366 grams, about the same weight as a Rebel SL1 (370 grams), but lighter and smaller than an Olympus Pen E-P5 (420 grams) and E-P3 (369 grams). It feels cramped in my medium hands—more cramped than my old Pen E-P3—and I have to squeeze more to keep from dropping it. Obviously a Rebel, 6D or 80D is more comfortable for long sessions or use with larger optics but I bought the M3 for snapshots so I don't need to hold it very long.
Canon EOS M3 & EF-M 22mm 2.0 STM and Olympus Pen E-P3 and 17mm 2.8. The contoured grip makes the M3 fatter than Pen models but easier to hold.
The M3 is not as handsome nor as retro in styling as an Olympus Pen-F or E-P3. Not that it's ugly. It looks like a PowerShot S-series point 'n shoot: petite, modern and understated.
Canon EOS M3 | Photo courtesy Canon Inc.
The EF-M lens mount is similar to the EF mount on EOS DSLRs but smaller and not directly compatible. As of this writing, there are only seven EF-M AF lenses available (eight if you count the Tamron 18-200). With that said, I love the EF-M 22mm 2.0 STM and EF-M 18-55 3.5-5.6 IS STM: sharp, small and cover my snapshot needs perfectly.
With an adapter, M series cameras can use EF and EF-S lenses with full AF and auto diaphragm compatibility. And AF performance is as good as a native EF-M lens. My only nibble with the adapter is it's incompatible with system sleep when a lens with Image Stabilization (IS) is used: activate AF and IS runs continuously until the battery dies! In other words, system sleep doesn’t turn IS off. Oddly, even LCD/EVF sleep is delayed by several minutes. The workaround is to disable IS on the EF/EF-s lens (or turn the camera off) but it's easy to forget to do since I’m used to EF-M lenses sleeping within 30 seconds.
Ergonomically the M3 is a couple levels below the speed and comfort of a Canon DSLR but easier to use than Canon S series and Olympus Pens. What makes the M3 harder to use than a Canon DSLR? It's mostly about the size: small grip, small controls and fewer physical controls make it less user friendly.
Unlike a DSLR, the M3 is frustratingly slow to wake from sleep mode and requires the extra step of pressing the on-off switch rather than simply touching the shutter button. The 2-second delay of the EVF or LCD illuminating after system sleep has cost me many a shot.
Holding That Darn Thing
The first EOS M, like early S series, was shaped like a rounded off bar of soap. There just wasn't much to hold on to. However, the EOS M3 has a substantial grip, improving greatly on M/M2 ergonomics. Nevertheless, even after several months of practice, I can't hold the M3 as consistently steady as my 80D and 6D. The grip is so close to the lens, my fingertips hit the lens, preventing a secure wrap around grip posture. In other words, I'm holding the camera mainly with fingertips rather than with fingers and palm wrapped around the camera. Less weight and grip area result in more camera shake and, thus, a higher percentage of blurred images compared to larger and heavier cameras.
Wee Honey Bee | EOS M3 and EF-M 28 3.5 Macro IS
STM
Controls
The two input wheels are small but work well by feel while looking through the EVF. I especially like the topside exposure compensation dial. Rear buttons are small, set flush and tightly spaced, so tricky to use unless looking at them. The tiny video start and playback buttons are difficult to use: set flush, positioned awkwardly on the thumb rest and hard to press.
Many button functions can be changed to fit individual preferences, e.g., move AF start to the * button. I have AF mode assigned to the M-Fn button as I toggle between modes frequently.
Canon EOS M3 | Photo courtesy Canon Inc.
Manual, semi-auto and auto modes exposure modes are set with a large knurled topside dial: Program (P), Aperture Priority (Av), Shutter Priority (Tv) and Manual (M) and assorted Full Auto modes. If you've owned a prior EOS model the interface is similar and you won't need to crack the manual.
The LCD has a tabbed menu: four icons organized by category. Menus are color coded and sport four or five numbered submenus. One menu is reserved for for quick access to favorite settings. Only six favorites are allowed and the body of selections is needlessly curtailed: "format" can't be chosen as a favorite.
I'm a guitar player so my fingertips are tough and smooth and don't work well on many touch screens, including the M3 at default. Fortunately, the M3 has adjustable touch sensitivity. With sensitivity set to the highest level, touch screen operation is silky smooth and responsive! I noticed the LCD is prone to fingerprints: the M3 lacks the anti-smudge coating found on the 80D LCD. Nevertheless, LCD clarity is excellent, albeit, like all LCDs, is difficult to see outdoors during the day. I use the EVF-DC1 Electronic Viewfinder most of the time so no problem composing even on white sand beaches!
Canon EOS M3 | LCD can be reversed above or below the camera for easy video blogging or selfies | Photo courtesy Canon Inc.
While the LCD can tilt and flip, the angles are odd as they require removal of the EVF (or Speedlite) or prevent the use of a tripod. Unlike the 60D/70D/80D, the LCD doesn't swing out to the side, the preferred position for video shooting on a tripod or shoulder rig. However, the top and bottom flip positions are ideal for arm's length selfie and video blogging.
The immediate display of an image after shooting can be disabled. Nothing worse than being in the heat of the moment and having the image you just took appear on the LCD or EVF, delaying and befuddling the composition of the next frame. Go to the "Camera 1" tab, select "Image Review" and set "No image display after shots." You now have to press the playback button to see the last shot but the LCD/EVF is clean and immediately available for composition.
Unlike recent Canon DSLRs with both phase-detect and contrast-based AF, the M3 only employs contrast-based AF. Under ideal lighting conditions, contrast-based AF is slightly more accurate than phase-detect AF and, unlike phase-detect AF, never needs AFMA calibration. Contrast-based AF is also more intelligent than phase-detect AF, able to recognize faces more readily. Sadly, contrast-based AF stumbles in low light and low contrast situations phase-detect AF has no problems with. Also the M3's contrast-based AF is much slower than phase-detect AF, so not a good choice for sports.
The M3 has two AF area options: Face with Tracking (49 points) or one-point. Face mode automatically locks onto a face. If a face isn't present, it switches to an auto-area option. Tap the screen in Face Tracking mode and an AF point follows it on screen. Choose One-point and the AF area can be positioned using the rocker switch or touch-screen. One-point AF is my preferred method of focus. Why? AF is faster and more sure-footed, the camera doesn't second guess my subject choice and I get more sharp images.
Auto focus—Hybrid CMOS AF III—is accurate and faster than the original M or the SL1's live view Hybrid focus. No problem tracking moving cars or bicycles in good light with Servo mode. On the other hand, the SL1's 9-point AF array (viewfinder AF) buries the M3 in terms of speed and low light use. Compared to my 2011 Pen E-P3 with 17mm 2.8 pancake, the M3 and 22mm 2.0 pancake focus a little faster. So serviceable AF but not class defining and significantly slower than Rebels and mid priced DSLRs such as the 70D and 80D.
One thing that bothered me initially was continuous focus (servo) was always on in still picture modes. In other words, the darn thing focused automatically, rather than when the shutter button was half-pressed. Smartphone users may love this feature but I found it distracting: often focused on something besides my subject. A visit to the menu disabled automatic continuous focus and now, like my DSLR, I half press the shutter button to focus. Less frustration and the battery lasts longer!
Wired Pigeons | Canon EOS M3 and EF-M 22 2.0 STM
One oddity with single point AF is difficulty locking on horizontal lines, e.g., black line on a white wall or telephone wire across a blue sky. Single axis AF points on DSLRs of yesteryear suffered the same disability. This problem vaporized with the introduction of cross AF-points sensitive to both horizontal and vertical lines. Luckily there's a fast workaround: tilt the M3 slightly, lock AF on the horizontal line (keep shutter button half-depressed), recompose and take the shot. In fairness, you may not notice this problem in 49-point AF mode as the M3 usually focuses on something else besides the horizontal line.
If you shoot wide angle landscapes with big sky, AF has difficulty with clouds even in bright light. I'm used to DSLRs easily locking on clouds this behavior surprised me. The fastest workaround is to use the AE lock (*) button to lock exposure for the sky, use the shutter button to lock AF on a contrasty land object at infinity, and recompose with big sky and clouds in viewfinder. If you're shooting a lot of big sky images, M mode is better you don't have to monkey with two buttons.
In low light an AF assist light is projected so focus is reasonably peppy for close subjects. However, once out of range of the AF assist light, hybrid focus struggles in low light and any entry level Rebel will whip it good. My workaround is to select a single AF point and lock on a point of contrast, e.g., a streetlight, or use manual focus. Manual focus is well implemented once you enable focus peaking and magnification in the menus.
Low light focus is faster and more sure-footed with large aperture lenses. The EF-M 22 2.0 STM focuses significantly faster and more reliably in low light than the EF-M 18-55 3.5-5.6 IS STM. In single point mode, it rarely misses. Hopefully more fast primes will be available soon.
The bottom line is AF is fine for snapshots and macro in good light. With a fast prime and thoughtful use of single point AF mode it does okay in most low light situations. However, if you mainly point 'n shoot in full auto and multi-point AF mode, expect constant focusing problems in low light (and cussing).
M3 image quality is excellent: vivid, detailed and well focused. The 24.2MP CMOS is a step up from the 18MP CMOS in the SL1 and nipping at the toes of the 80D. RAW files process well in Canon DPP and Apple's Aperture and Photos apps. Raw files even open in Apple's Preview (system level RAW support).
Since I own another 24.2 CMOS sensor Canon camera, the EOS 80D, I'll offer a few observations. In decent light, both cameras are nearly identical in terms of image quality. However, the one-year newer 80D tolerates shadow lifting and hard core image processing better. Also, blue skies and high ISO are noticeably cleaner on the 80D. For my image taste—save for photo emergencies—I avoid using the M3 at ISO settings beyond 1600.
Flash
Deploy the popup flash by sliding a spring-loaded side button (auto erects in Intelligent Auto Mode). The switch is stiff so inadvertent enabling should be rare. Since the M3 has an AF assist lamp, the popup is not used for AF assist.
M3 Slow Sync Flash | Canon EOS M3 and EF-M 22 2.0 STM | Popup flash balances subject with background light.
Popup flash range is limited to GN5m but works fine for close work and fill. Press the flash icon on the rocker switch and turn the rear wheel to choose from auto fill, always on and slow sync flash modes. And flash exposure compensation (FEC) isn't buried in a menu: input FEC by pressing the flash icon rocker and turning the wheel around the shutter button. These features are only available with a flash in the shoe or popup engaged.
Flash is generally well-exposed in both fill-in and main light modes. However, in really dim light, using slow sync mode, the M3 over exposes both flash and ambient light. Thus, in dim light, I need to input -1/3 to -1.0 EV flash exposure compensation (FEC) to offset slow sync flash overexposure. And, the dimmer the light, the more FEC needed. Ambient light is similar when flash is used: the darker the conditions, the more exposure compensation (EC) needed, typically -2/3 to 1.0 EV. With flash mode off, ambient exposure is accurate or slightly over exposed. If you shoot in dim bars and casinos, you'll get lots of practice diddling EC and FEC.
Wireless flash is available only with a master capable Speedlite or controller. I used a 90EX to trigger a 430EX II and it worked fine for both bounce and direct flash.
Canon EOS M3 | Photo courtesy Canon Inc.
Auto ISO and Flash
M3 auto ISO in flash mode gave me a pleasant surprise. Most Canon cameras default to ISO 400 when flash is activated in Auto ISO mode. If using fill flash in bright light, the background blows out due to the combination of low maximum sync speed (1/200 sec.) and high ISO. In dim light, ISO 400 often results in camera shake. M3 Auto ISO mode solves this problem by setting ISO appropriate to the situation. For example, for fill flash in bright sunlight, it sets ISO 100. In dim restaurants I frequently saw ISO 800. Not sure why Canon engineers didn't implement this improvement in the 80D and other DSLRs but it's a very welcome feature of the M3.
I don't use the M3 for concert or music videos. But I love M3 video for travel and casual use. Like the 80D and SL1, the M3 features Movie Servo: camcorder-like follow focus. A great feature for casual video shooters. Movie Servo works well but feels less snappy and sure-footed than the 80D, but more responsive than the SL1.
Canon was really stingy with video features as M3 video quality tops out with 1080p at 30fps. There are two video exposure modes: auto and manual. So no semi-auto modes like Av or Tv. The built-in mono mic isn't very good but there's a stereo input for an external microphone if you wish to up the audio quality.
HD video quality is very good to my eyes but quality falls short of my 70D and 80D due to lower bit rates and higher compression. M3 video options are considerably fewer than the 80D and, at default, appear over sharpened. M3 video really starts to show its weakness in dim light, taking on a gritty appearance.
The most negative thing about M3 video is the microscopic video start button: a flush red dot near the thumb rest. Not easy to use when you need it but prone to being pressed when you don't!
One thing I love about shooting video on the M3 is the tilting EVF. With camera braced against my face and elbows in my chest, I can precisely compose and pan silky smooth with my body, something nearly impossible to do with a camera at arm's length. For video, a tilting EVF is much more desirable than a fixed EVF and one of the reasons I choose this camera over the M5.
Battery
The original M and SL1 use LP-E12 batteries whereas the M3, M5, M6 and T6i/T6s use the LP-E17. Although these two batteries are nearly identical in appearance and specs, they are not interchangeable. Why a different battery? I suspect it's because the LP-E12 was easy to clone and inexpensive batteries from Wasabi, STK and others were stealing Canon's thunder.
The LP-E17 and it's charger (LC-E17) were "improved" with a chip to discourage use of aftermarket batteries. Thus, LP-E17 clones will not charge in Canon chargers. Place a clone battery in a M3 and the LCD displays "Battery communication error." It asks "does this battery display the Canon logo?" You must tap no (yes, turns off the camera). The next screen proclaims "Canon does not guarantee the performance or safety of this battery. Continue use?" If you tap yes, the camera and battery will work fine. If you tap no, the camera shuts off.
The final battery bugaboo is LP-E17 clones disable the M3 level indicator (the battery icon disappears). So carrying a spare battery is essential. Eventually, somebody will reverse engineer Canon's battery chip and dance around the before mentioned problems until the next battery redesign.
At camera defaults, I got about 250 RAW images per charge with basic chimping and no video or Wi-Fi use. With continuous focus disabled and EVF (LCD switching disabled) I can squeeze out about 350 RAWs. In contrast, my 6D and 80D bang out 1200+ while my Olympus E-P5 barely got 300. So carry a spare battery. At $60 a pop, OME batteries are expensive. Short battery life is the M3's biggest fault and why I don't use this camera on stage.
Canon LP-E17 Battery Pack | Photo courtesy Canon Inc.
Arca Compatible Quick Release Plate
My tripods and monopods are fitted with Arca-compatible clamps so I needed a quick release plate for the M3. There are no dedicated M3 plates from RRS, Kirk or ProMedia and most universal plates are too large and block the battery door. I found a few fitted L-brackets on Ebay sold direct from China. However, I wanted to keep my M3 slim and petite. I tried a RRS BPnS, a small 38mm bidirectional plate, but it was too big: covered the battery door and impeded LCD movements. So I mounted a ProMedia PX1 I had laying around, a tiny 25mm Arca compatible plate for point-n-shoots, and it fit perfectly: battery access, no interference with the articulating LCD and maintains a slim profile. Oddly, that little bump on the bottom gives me a little more secure grip when handling the camera.
The Sunwayfoto DP-26 also fits the M3 and allows battery access. Most 25 or 26mm plates should fit as long as they have an offset mounting hole. If the hole is centered, the plate will block the battery door.
Canon EOS M3 with EVF-DC1 and ProMedia Arca-compatible plate
Musings
I carried the M3 in my messenger bag for months and is so light I barely noticed it. I enjoyed using it for snaps along the road and found it a wonderful supplement to my Canon DSLRs. It's my 5th mirrorless camera and the first one I was able to get mostly sharp images with: intuitive operation, no shutter shock blur and great image quality. I'm not a fan of composing at arm's length so the EVF-DC1 Electronic Viewfinder is a must-have, albeit a mediocre design. I wrote a separate review of the EVF-DC1 here.
Nevertheless, the M3 is a niche product, appealing mainly to EOS DSLR owners wanting a small camera with high image quality for casual use. The M3 is not a good DSLR replacement due to a lack of lens choices, short battery life and mediocre AF. However, it's a nice upgrade to a point 'n shoot or smartphone. The tilting LCD and EVF make it ideal for ground level macro and shooting small products. Put it on a tripod and it's an excellent poor man's landscape camera.
If you're looking for one camera to do everything from sports to low light, the SL2, T7i, 77D, 70D and 80D are better choices: slightly better image quality but significantly better AF (phase-detect and contrast AF), frame rate, ergonomics and lens choices. Plus, you can operate them in Live View mode like a mirrorless camera and their Dual Pixel AF is significantly better than the M3's Hybrid CMOS AF III. Of course they're larger than the M3. If small is important but you need faster phase-detect AF, the SL1 is the same weigh as the M3 and strikes a nice compromise between size and features.
2/26/2020 Update: The replacement model for the M3, the M6, has significantly better Dual Pixel AF, albeit image quality is only slightly improved. And it can focus on clouds! It is a better alternative to the M3, especially as a closeout or refurb in 2020. The M6 MK II, the current model, is even better but at much higher price.
Final Blurb
The uniqueness of the M3 is it's PowerShot sized, sports DSLR image quality and uses interchangeable lenses. If you're an EOS DSLR user looking for a small as possible APS-C camera for snapshots and kicking around town this may be the camera for you.
Major Features
• Sensor: 24.2 MP CMOS | 22.3mm x 14.9mm (APS-C) | 6000 x 4000
• 49-Point AF Hybrid Contrast and Phase Detect array
• AF modes: Multi-area, Selective single-point, Tracking, Touch, Face Detection
• Metering: 384 Zone Evaluative, center
weighted, partial (10%) and spot (2%)