Canon T6s vs Olympus E-M1

The Canon EOS Rebel T6s (called Canon 760D in some regions) and the Olympus OM-D E-M1 are two digital cameras that were officially introduced, respectively, in February 2015 and September 2013. The T6s is a DSLR, while the E-M1 is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (T6s) and a Four Thirds (E-M1) sensor. The Canon has a resolution of 24 megapixels, whereas the Olympus provides 15.9 MP.

Below is an overview of the main specs of the two cameras as a starting point for the comparison.

Headline Specifications

Canon T6s		Olympus E-M1
Digital single lens reflex		Mirrorless system camera
Canon EF mount lenses		Micro Four Thirds lenses
24 MP – APS-C sensor		15.9 MP – Four Thirds sensor
1080/30p Video		1080/30p Video
ISO 100-12,800 (100 - 25,600)		ISO 200-25,600
Optical viewfinder		Electronic viewfinder (2360k dots)
3.0" LCD – 1040k dots		3.0" LCD – 1037k dots
Swivel touchscreen		Tilting touchscreen
5 shutter flaps per second		10 shutter flaps per second
Lens stabilization only		In-body stabilization
not weather sealed		Weathersealed body
440 shots per battery charge		350 shots per battery charge
132 x 101 x 78 mm, 565 g		130 x 94 x 63 mm, 497 g

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Check E-M1 offers at
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Going beyond this snapshot of core features and characteristics, what are the differences between the Canon EOS Rebel T6s and the Olympus OM-D E-M1? Which one should you buy? Read on to find out how these two cameras compare with respect to their body size, their imaging sensors, their shooting features, their input-output connections, and their reception by expert reviewers.

Body comparison

An illustration of the physical size and weight of the Canon T6s and the Olympus E-M1 is provided in the side-by-side display below. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All width, height and depth measures are rounded to the nearest millimeter.

The E-M1 can be obtained in two different colors (black, silver), while the T6s is only available in black.

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Olympus E-M1 is notably smaller (8 percent) than the Canon T6s. Moreover, the E-M1 is markedly lighter (12 percent) than the T6s. It is noteworthy in this context that the E-M1 is splash and dust-proof, while the T6s does not feature any corresponding weather-sealing.

The above size and weight comparisons are to some extent incomplete since they do not consider the interchangeable lenses that both of these cameras require. A larger imaging sensor will tend to go along with bigger and heavier lenses, although exceptions exist. You can compare the optics available for the two cameras in the Canon EF Lens Catalog (T6s) and the Micro Four Thirds Lens Catalog (E-M1). Mirrorless cameras, such as the E-M1, have moreover the advantage that they can use many lenses from other systems via adapters, as they have a relatively short flange to focal plane distance.

Concerning battery life, the T6s gets 440 shots out of its LP-E17 battery, while the E-M1 can take 350 images on a single charge of its BLN-1 power pack.

The following table provides a synthesis of the main physical specifications of the two cameras and other similar ones. If you would like to visualize and compare a different camera combination, you can navigate to the CAM-parator app and make your selection from a broad list of cameras there.

Body Specifications

		Camera Model	Camera Width	Camera Height	Camera Depth	Camera Weight	Battery Life	Weather Sealing	Camera Launch	Launch Price (USD)	Street Price
1.		Canon T6s	132 mm	101 mm	78 mm	565 g	440	n	Feb 2015	649	ebay.com
2.		Olympus E-M1	130 mm	94 mm	63 mm	497 g	350	Y	Sep 2013	1,399	ebay.com
3.		Canon 77D	131 mm	100 mm	76 mm	540 g	600	n	Feb 2017	899	ebay.com
4.		Canon T7i	131 mm	100 mm	76 mm	532 g	600	n	Feb 2017	749	ebay.com
5.		Canon T6i	132 mm	101 mm	78 mm	555 g	440	n	Feb 2015	749	ebay.com
6.		Canon T5	130 mm	100 mm	78 mm	480 g	500	n	Feb 2014	449	ebay.com
7.		Canon T4i	133 mm	100 mm	79 mm	575 g	440	n	Jun 2012	849	ebay.com
8.		Canon T2i	129 mm	98 mm	62 mm	530 g	440	n	Feb 2010	699	ebay.com
9.		Canon T1i	129 mm	98 mm	62 mm	520 g	400	n	Mar 2009	799	ebay.com
10.		Canon XSi	129 mm	98 mm	62 mm	524 g	500	n	Jan 2008	799	ebay.com
11.		Canon XTi	127 mm	84 mm	65 mm	556 g	370	n	Aug 2006	799	ebay.com
12.		Canon XT	127 mm	94 mm	64 mm	540 g	400	n	Feb 2005	899	ebay.com
13.		Olympus E-M1 II	134 mm	91 mm	67 mm	574 g	440	Y	Sep 2016	1,999	ebay.com
14.		Olympus PEN-F	125 mm	72 mm	37 mm	427 g	330	n	Jan 2016	1,199	ebay.com
15.		Olympus E-M5 II	124 mm	85 mm	45 mm	469 g	310	Y	Feb 2015	1,099	ebay.com
16.		Olympus E-P5	122 mm	69 mm	37 mm	420 g	330	n	May 2013	999	ebay.com
17.		Olympus E-M5	122 mm	89 mm	43 mm	425 g	360	Y	Feb 2012	1,299	ebay.com
Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
Convert to Imperial

The price is, of course, an important factor in any camera decision. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The T6s was launched at a markedly lower price (by 54 percent) than the E-M1, which puts it into a different market segment. Usually, retail prices stay at first close to the launch price, but after several months, discounts become available. Later in the product cycle and, in particular, when the replacement model is about to appear, further discounting and stock clearance sales often push the camera price considerably down.

Sensor comparison

The size of the sensor inside a digital camera is one of the key determinants of image quality. A large sensor will generally have larger individual pixels that offer better low-light sensitivity, provide wider dynamic range, and have richer color-depth than smaller pixels in a sensor of the same technological generation. Moreover, a large sensor camera will give the photographer more control over depth-of-field in the image and, thus, the ability to better isolate a subject from the background. On the downside, larger sensors tend to be associated with larger, more expensive camera bodies and lenses.

Of the two cameras under consideration, the Canon T6s features an APS-C sensor and the Olympus E-M1 a Four Thirds sensor. The sensor area in the E-M1 is 32 percent smaller. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.6 and 2.0. The sensor in the T6s has a native 3:2 aspect ratio, while the one in the E-M1 offers a 4:3 aspect.

With 24MP, the T6s offers a higher resolution than the E-M1 (15.9MP), but the T6s has marginally smaller individual pixels (pixel pitch of 3.72μm versus 3.76μm for the E-M1). However, the T6s is a somewhat more recent model (by 1 year and 4 months) than the E-M1, and its sensor might have benefitted from technological advances during this time that enhance the light gathering capacity of its pixels. Coming back to sensor resolution, it should be mentioned that the E-M1 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The resolution advantage of the Canon T6s implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the T6s for good quality output (200 dots per inch) amounts to 30 x 20 inches or 76.2 x 50.8 cm, for very good quality (250 dpi) 24 x 16 inches or 61 x 40.6 cm, and for excellent quality (300 dpi) 20 x 13.3 inches or 50.8 x 33.9 cm. The corresponding values for the Olympus E-M1 are 23 x 17.3 inches or 58.5 x 43.9 cm for good quality, 18.4 x 13.8 inches or 46.8 x 35.1 cm for very good quality, and 15.4 x 11.5 inches or 39 x 29.3 cm for excellent quality prints.

The Canon EOS Rebel T6s has a native sensitivity range from ISO 100 to ISO 12800, which can be extended to ISO 100-25600. The corresponding ISO settings for the Olympus OM-D E-M1 are ISO 200 to ISO 25600, with the possibility to increase the ISO range to 100-25600.

Technology-wise, both cameras are equipped with CMOS (Complementary Metal–Oxide–Semiconductor) sensors. Both cameras use a Bayer filter for capturing RGB colors on a square grid of photosensors. This arrangement is found in most digital cameras.

Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. This service assesses and scores the color depth ("DXO Portrait"), dynamic range ("DXO Landscape"), and low-light sensitivity ("DXO Sports") of camera sensors, and also publishes an overall camera score. The Overall DXO ratings for the two cameras under consideration are close, suggesting that they provide similar imaging performance. The table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.

Sensor Characteristics

		Camera Model	Sensor Class	Resolution (MP)	Horiz. Pixels	Vert. Pixels	Video Format	DXO Portrait	DXO Landscape	DXO Sports	DXO Overall
1.		Canon T6s	APS-C	24.0	6000	4000	1080/30p	22.6	12.0	915	70
2.		Olympus E-M1	Four Thirds	15.9	4608	3456	1080/30p	23.0	12.7	757	73
3.		Canon 77D	APS-C	24.0	6000	4000	1080/60p	23.6	13.3	971	78
4.		Canon T7i	APS-C	24.0	6000	4000	1080/60p	23.7	13.1	1586	80
5.		Canon T6i	APS-C	24.0	6000	4000	1080/30p	22.7	12.0	919	71
6.		Canon T5	APS-C	17.9	5184	3456	1080/30p	21.9	11.3	724	63
7.		Canon T4i	APS-C	17.9	5184	3456	1080/30p	21.7	11.2	722	62
8.		Canon T2i	APS-C	17.9	5184	3456	1080/30p	22.1	11.5	784	66
9.		Canon T1i	APS-C	15.1	4752	3168	1080/20p	21.7	11.5	663	63
10.		Canon XSi	APS-C	12.2	4272	2848	none	21.9	10.8	692	61
11.		Canon XTi	APS-C	10.1	3888	2592	none	22.1	11.0	664	62
12.		Canon XT	APS-C	8.0	3456	2304	none	21.8	10.8	637	60
13.		Olympus E-M1 II	Four Thirds	20.2	5184	3888	4K/30p	23.7	12.8	1312	80
14.		Olympus PEN-F	Four Thirds	20.2	5184	3888	1080/60p	23.1	12.4	894	74
15.		Olympus E-M5 II	Four Thirds	15.9	4608	3456	1080/60p	23.0	12.5	842	73
16.		Olympus E-P5	Four Thirds	15.9	4608	3456	1080/30p	22.8	12.4	895	72
17.		Olympus E-M5	Four Thirds	15.9	4608	3456	1080/60i	22.8	12.3	826	71
Note: DXO values in italics represent estimates based on sensor size and age.

Many modern cameras cannot only take still pictures, but also record videos. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, and both provide the same movie specifications (1080/30p).

Feature comparison

Apart from body and sensor, cameras can and do differ across a range of features. For example, the E-M1 has an electronic viewfinder (2360k dots), while the T6s has an optical one. Both systems have their advantages, with the electronic viewfinder making it possible to project supplementary shooting information into the framing view, whereas the optical viewfinder offers lag-free viewing and a very clear framing image. The viewfinder in the E-M1 offers a wider field of view (100%) than the one in the T6s (95%), so that a larger proportion of the captured image is visible in the finder. In addition, the viewfinder of the E-M1 has a higher magnification (0.74x vs 0.51x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The following table reports on some other key feature differences and similarities of the Canon T6s, the Olympus E-M1, and comparable cameras.

Core Features

		Camera Model	Viewfinder (Type or 000 dots)	Control Panel (yes/no)	LCD Specifications (inch/000 dots)	LCD Attach- ment	Touch Screen (yes/no)	Max Shutter Speed *	Max Shutter Flaps *	Built-in Flash (yes/no)	Built-in Image Stab
1.		Canon T6s	optical	Y	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
2.		Olympus E-M1	2360	n	3.0 / 1037	tilting	Y	1/8000s	10.0/s	n	Y
3.		Canon 77D	optical	Y	3.0 / 1040	swivel	Y	1/4000s	6.0/s	Y	n
4.		Canon T7i	optical	n	3.0 / 1040	swivel	Y	1/4000s	6.0/s	Y	n
5.		Canon T6i	optical	n	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
6.		Canon T5	optical	n	3.0 / 460	fixed	n	1/4000s	3.0/s	Y	n
7.		Canon T4i	optical	n	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
8.		Canon T2i	optical	n	3.0 / 1040	fixed	n	1/4000s	3.7/s	Y	n
9.		Canon T1i	optical	n	3.0 / 920	fixed	n	1/4000s	3.4/s	Y	n
10.		Canon XSi	optical	n	3.0 / 230	fixed	n	1/4000s	3.5/s	Y	n
11.		Canon XTi	optical	n	2.5 / 230	fixed	n	1/4000s	3.0/s	Y	n
12.		Canon XT	optical	n	1.8 / 115	fixed	n	1/4000s	3.0/s	Y	n
13.		Olympus E-M1 II	2360	n	3.0 / 1037	swivel	Y	1/8000s	18.0/s	n	Y
14.		Olympus PEN-F	2360	n	3.0 / 1037	swivel	Y	1/8000s	10.0/s	n	Y
15.		Olympus E-M5 II	2360	n	3.0 / 1037	swivel	Y	1/8000s	10.0/s	n	Y
16.		Olympus E-P5	optional	n	3.0 / 1037	tilting	Y	1/8000s	9.0/s	Y	Y
17.		Olympus E-M5	1440	n	3.0 / 610	tilting	Y	1/4000s	9.0/s	n	Y
Notes: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One difference between the cameras concerns the presence of an on-board flash. The T6s has one, while the E-M1 does not. While the built-in flash of the T6s is not very powerful, it can at times be useful as a fill-in light.

The reported shutter speed information refers to the use of the mechanical shutter. Yet, some cameras only have an electronic shutter, while others have an electronic shutter in addition to a mechanical one. In fact, the E-M1 is one of those camera that have an additional electronic shutter, which makes completely silent shooting possible. However, this mode is less suitable for photographing moving objects (risk of rolling shutter) or shooting under artificial light sources (risk of flickering).

The Olympus E-M1 has an intervalometer built-in. This enables the photographer to capture time lapse sequences, such as flower blooming, a sunset or moon rise, without purchasing an external camera trigger and related software.

Concerning the storage of imaging data, both the T6s and the E-M1 write their files to SDXC cards. Both cameras can use UHS-I cards, which provide for Ultra High Speed data transfer of up to 104 MB/s.

Connectivity comparison

For some imaging applications, the extent to which a camera can communicate with its environment can be an important aspect in the camera decision process. The table below provides an overview of the connectivity of the Canon EOS Rebel T6s and Olympus OM-D E-M1 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

Input-Output Connections

		Camera Model	Hotshoe Port	Internal Mic / Speaker	Microphone Port	Headphone Port	HDMI Port	USB Port	WiFi Support	NFC Support	Bluetooth Support
1.		Canon T6s	Y	stereo / mono	Y	-	mini	2.0	Y	Y	-
2.		Olympus E-M1	Y	stereo / mono	Y	-	micro	2.0	Y	-	-
3.		Canon 77D	Y	stereo / mono	Y	-	mini	2.0	Y	Y	Y
4.		Canon T7i	Y	stereo / mono	Y	-	mini	2.0	Y	Y	Y
5.		Canon T6i	Y	stereo / mono	Y	-	mini	2.0	Y	Y	-
6.		Canon T5	Y	mono / mono	-	-	mini	2.0	-	-	-
7.		Canon T4i	Y	stereo / mono	Y	-	mini	2.0	-	-	-
8.		Canon T2i	Y	stereo / -	Y	-	mini	2.0	-	-	-
9.		Canon T1i	Y	mono / mono	-	-	mini	2.0	-	-	-
10.		Canon XSi	Y	- / -	-	-	mini	2.0	-	-	-
11.		Canon XTi	Y	- / -	-	-	-	2.0	-	-	-
12.		Canon XT	Y	- / -	-	-	-	2.0	-	-	-
13.		Olympus E-M1 II	Y	stereo / mono	Y	Y	micro	3.0	Y	-	-
14.		Olympus PEN-F	Y	stereo / mono	-	-	micro	2.0	Y	-	-
15.		Olympus E-M5 II	Y	stereo / mono	Y	-	micro	2.0	Y	-	-
16.		Olympus E-P5	Y	stereo / mono	-	-	micro	2.0	Y	-	-
17.		Olympus E-M5	Y	stereo / mono	-	-	mini	2.0	-	-	-

Studio photographers will appreciate that the Olympus E-M1 (unlike the T6s) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.

Both the T6s and the E-M1 have been discontinued, but can regularly be found used on ebay. The E-M1 was replaced by the Olympus E-M1 II, while the T6s was followed by the Canon 77D. Further information on the features and operation of the T6s and E-M1 can be found, respectively, in the Canon T6s Manual (free pdf) or the online Olympus E-M1 Manual.

Review summary

So what is the bottom line? Is there a clear favorite between the Canon T6s and the Olympus E-M1? Which camera is better? A synthesis of the relative strong points of each of the models is listed below.

Reasons to prefer the Canon EOS Rebel T6s:

• More detail: Offers more megapixels (24 vs 15.9MP) with a 25% higher linear resolution.
• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• Brighter framing: Features an optical viewfinder for clear, lag-free composition.
• Easier setting verification: Features an LCD display on top to control shooting parameters.
• More flexible LCD: Has a swivel screen for odd-angle shots in portrait or landscape orientation.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Longer lasting: Can take more shots (440 versus 350) on a single battery charge.
• Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
• Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
• More affordable: Was introduced into a lower priced category (54 percent cheaper at launch).
• More modern: Is somewhat more recent (announced 1 year and 4 months after the E-M1).

Arguments in favor of the Olympus OM-D E-M1:

• Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
• More dynamic range: Captures a broader range of light and dark details (0.7 EV of extra DR).
• More framing info: Has an electronic viewfinder that displays shooting data.
• More complete view: Has a viewfinder with a larger field of view (100% vs 95%).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.74x vs 0.51x).
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (10 vs 5 flaps/sec) to capture the decisive moment.
• Less disturbing: Has an electronic shutter option for completely silent shooting.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• Less heavy: Has a lower weight (by 68g or 12 percent) and is thus easier to take along.
• Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
• Sharper images: Has stabilization technology built-in to reduce the impact of hand-shake.
• More legacy lens friendly: Can use many non-native lenses via adapters.
• Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
• More heavily discounted: Has been on the market for longer (launched in September 2013).

If the count of individual advantages (bullet points above) is taken as a guide, the E-M1 is the clear winner of the contest (15 : 11 points). However, the relative importance of the various individual camera aspects will vary according to personal preferences and needs, so that you might like to apply corresponding weights to the particular features before making a decision on a new camera. A professional wedding photographer will view the differences between cameras in a way that diverges from the perspective of a travel photog, and a person interested in cityscapes has distinct needs from a macro shooter. Hence, the decision which camera is best and worth buying is often a very personal one.

How about other alternatives? Do the specifications of the Canon T6s and the Olympus E-M1 place the cameras among the top in their class? Find out in the latest Best DSLR Camera and Best Mirrorless Interchangeable Lens Camera listings whether the two cameras rank among the cream of the crop.

In any case, while the specs-based evaluation of cameras can be instructive in revealing their potential as photographic tools, it remains incomplete and does no justice, for example, to the way the T6s or the E-M1 perform in practice. User reviews that are available, for instance, at amazon can sometimes shed light on these issues, but such feedback is all too often partial, inconsistent, and inaccurate.

Expert reviews

This is where reviews by experts come in. The following table reports the overall ratings of the cameras as published by some of the major camera review sites (amateurphotographer [AP], cameralabs [CL], digitalcameraworld [DCW], dpreview [DPR], ephotozine [EPZ], photographyblog [PB]). As can be seen, the professional reviewers agree in many cases on the quality of different cameras, but sometimes their assessments diverge, reinforcing the earlier point that a camera decision is often a very personal choice.

Expert Camera Reviews

		Camera   Model	AP   score	CL   score	DCW   score	DPR   score	EPZ   score	PB   score	Camera Launch	Launch Price (USD)	Street Price
1.		Canon T6s	5/5	+	..	77/100	4.5/5	4.5/5	Feb 2015	649	ebay.com
2.		Olympus E-M1	5/5	+ +	..	84/100	4.5/5	4.5/5	Sep 2013	1,399	ebay.com
3.		Canon 77D	4.5/5	..	4/5	82/100	4.5/5	4/5	Feb 2017	899	ebay.com
4.		Canon T7i	4.5/5	..	3.5/5	80/100	4.5/5	4/5	Feb 2017	749	ebay.com
5.		Canon T6i	5/5	..	..	75/100	4.5/5	4.5/5	Feb 2015	749	ebay.com
6.		Canon T5	3/5	+	..	..	4/5	4.5/5	Feb 2014	449	ebay.com
7.		Canon T4i	4/5	+ +	..	77/100	4.5/5	4.5/5	Jun 2012	849	ebay.com
8.		Canon T2i	..	+ +	..	77/100	4/5	4.5/5	Feb 2010	699	ebay.com
9.		Canon T1i	..	+ +	..	74/100	4.5/5	4.5/5	Mar 2009	799	ebay.com
10.		Canon XSi	..	+ +	..	+ +	4/5	4.5/5	Jan 2008	799	ebay.com
11.		Canon XTi	..	+ +	..	+ +	o	4/5	Aug 2006	799	ebay.com
12.		Canon XT	..	80/100	..	+ +	o	..	Feb 2005	899	ebay.com
13.		Olympus E-M1 II	5/5	+ +	5/5	85/100	4.5/5	4.5/5	Sep 2016	1,999	ebay.com
14.		Olympus PEN-F	..	..	4/5	82/100	4.5/5	5/5	Jan 2016	1,199	ebay.com
15.		Olympus E-M5 II	5/5	+ +	4.5/5	81/100	5/5	5/5	Feb 2015	1,099	ebay.com
16.		Olympus E-P5	5/5	+ +	..	78/100	4.5/5	5/5	May 2013	999	ebay.com
17.		Olympus E-M5	4/5	+ +	..	80/100	4.5/5	5/5	Feb 2012	1,299	ebay.com
Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

Care should be taken when interpreting the review scores above, though. The ratings are only valid when referring to cameras in the same category and of the same age. Hence, a score should always be seen in the context of the camera's market launch date and its price, and comparisons of ratings among very different cameras or across long time periods have little meaning. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

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Other camera comparisons

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