On July 23rd, 2012, Canon announced the beginnings of the EOS-M system with a new mount, two lenses, and an EF adapter.
This is the kit zoom lens, the 18-55 that was announced with the starting kit. This lens features a full frame focal range of 29 to 88mm and provided the initial kit zoom for the birth of the EOS M system.
Canon had this to say about the lens when they released it;
Two new EF-M lenses offer portability and high performance when using the new model – the EF-M 18-55mm f/3.5-5.6 IS STM standard zoom and the EF-M 22mm f/2 STM pancake lens. Both feature new Stepper Motor technology for exceptionally smooth AF performance, as well as precision Canon optics, while their compact designs offer the perfect form-factor to complement the camera’s pocket-sized body.
|CIPA IS rating
||3 aspheric elements
||Lead screw Stepper Motor
|Full time manual
||Graphite or Silver
This lens is an all-purpose zoom lens, consisting of a metal shell and a metal mount, and industrial plastic interior. It measures 61mm x 61mm and weighs a diminutive 210g. The filter size is 52mm. The barrel extends out while zooming and the mechanical assembly is tight, there is little wiggle or play in the barrel when extended.
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, which means that electronically the lens detects if you are spinning the focus wheel and moves the lens accordingly electronically. 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.
The optical design is 13 elements in 11 groups featuring three aspherical elements, making it a relatively complex kit lens. It has a minimum focus distance of 25cm, giving it an excellent .25x magnification.
The 18-55mm steadily reaches a minimum aperture of 5.6 from 3.5 from 18 to 45mm. It remains a constant minimum aperture of 5.6 from 45mm to 55mm.
Zoom Aperture Comparison
When compared to the other kit lenses, we see that the 18-55mm is close to the 18-150 and better than the 15-45 in between 18 and 55mm.
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 charts suggest that for a high ratio zoom lens, the EF-M 18-55mm will deliver good wide-open sharpness in the center, tailing off to the extremities, and very good performance stopped down to F/8. Telephoto at 55mm is also good with good contrast and sharpness throughout the frame. Contrast is good at 18mm throughout the frame, and tails off to the extremities, and improves significantly as you stop down the lens. Looking at the MTF, this lens is better as you increase the focal length.
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 well removing all traces of heavy CA especially at 18mm.
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 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.
As we can see from our example, it conforms well to the MTF diagram. The corners are good wide open the lens sharpens up in the corners as you stop down the lens. Center performance is excellent throughout the zoom range.
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.
A special note about the infrared test images. It's very common because lenses aren't designed to focus infrared light instead of visible light at the lenses are softer than what you'd see normally with color images. Depending on your filter choice, there's also a lot less RGB pixels receiving light, therefore, less sharpness. For infrared images, very aggressive sharpening and contrast curves are used to bring out as much as possible from the image. For a good judge of the image characteristics, click on the 2:1 button to reduce the image magnification down to 50%. We usually find most infrared images look exceptional at around 50% magnification. For each image, you can download and view to your own satisfaction.
Hot Spot Performance
There is a very distinct hotspot at all focal lengths and at most apertures. 28mm to 35mm is most likely the best infrared performance for this lens, however, even then, by F8 a hotspot will appear.
While the 18-55, shows good performance under color photography the same cannot be said for infrared. With the strong color cast in normal color photography, it gets exasperated even more under infrared. Resolution falls off, and at 18mm some slight smearing exists.
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.
The EF-M 18-55 has moderate vignetting wide open at 18mm and decreases as you increase both the aperture and also the focal length.
The 18-55 was one of the first lenses that came out for the EOS M system when it was announced in July 2012, however, Canon has very quietly discontinued use of this lens over the past 2 years since the 15-45 was released. Part of me thinks this was a bad move because for color photography it’s an excellent performer, only showing a slight color cast that under most circumstances unless you are shooting grey cards for a living, isn’t even noticeable in the real world.
You still source the lens new or lightly used on eBay and with some overseas sellers. With a definitive hot spot forming under some focal lengths, this is a lens to skip if you are shooting infrared. For those that only worry about color photography, this is a lens for you to pick up.