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Forum » Tin tức » Tin công nghệ » Canon EOS Rebel T6s (EOS 760D / EOS 8000D) (Canon EOS Rebel T6s (EOS 760D / EOS 8000D))
Canon EOS Rebel T6s (EOS 760D / EOS 8000D)
NguyenHoangDate: Thursday, 2017-04-13, 3:18 PM | Message # 1
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EOS Rebel T6s (760D) key features
  • 24.2MP APS-C CMOS sensor
  • 19-point autofocus system
  • Hybrid CMOS AF III focus system (live view)
  • 7560 pixel RGB + IR metering sensor with skin tone detection
  • 3" fully articulating touchscreen LCD
  • Eye sensor for use with optical viewfinder
  • LCD information display on top plate
  • Quick control dial on rear
  • 5 fps continuous shooting
  • 1080/30p video
  • Servo AF in live view
  • Wi-Fi with NFC

Other advancements come in the form of built-in Wi-Fi with NFC - a first in the EOS DSLRs range - and Flicker detection, first seen in the Canon EOS 7D Mark II, which also makes its way into both models.
The camera also retains several features from the Rebel T5i, including a fully articulating 3" touchscreen LCD, 5 fps continuous shooting, and 1080/30p video.
Specs comparedWhile the T6s shares many core features with the T6i, the user experience on the T6s/760D is aimed toward more advanced users. The T6s will cost $100/£50/€60 more than the T6i, and offer users a nice list of features to make that extra money spent worth it. These include a a top LCD screen - the first on any Rebel - a Quick Control dial on the back, and an eye sensor to shut off the LCD panel when you're shooting with the viewfinder. The T6s also offers Servo AF in Live View which allows for continuous AF in burst mode. The final advantage is the T6s' ability to record HDR movies in real time, a potentially nifty feature for budding film makers.
Before we get to those differences in detail, let's see how the the T6s compares with the T6i, as well as the Rebel T5i (700D) that is now the low-end model in Canon's DSLR lineup.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:19 PM | Message # 2
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Probably the biggest difference between the T6s and the T5i is the sensor. It's no secret that Canon has been using the same (or very similar) 18 Megapixel sensor since the Rebel T2i (EOS 550D). The new 24.2MP sensor catches up with the latest DSLRs from Nikon, Pentax, and Sony.
The other major addition is Wi-Fi with 'active' NFC.  If you're using an NFC-equipped phone (iPhone 6's don't count) then you can tap it against the camera to pair. If you don't, it's not terribly difficult. Once that's done you can remotely control the camera from your phone, transfer photos, and then share them with friends and family. If you set up Canon's Image Gateway service you can choose where photos go (and add comments) right on the camera.
The T6s (right) offers several things over the T6i, including an LCD info display, locking mode dial, and quick control dial (not pictured).Pricing and availabilityThe Rebel T6s (760D) is priced at $849/£649/€859 body only and $1199 bundled with an 18-135mm STM lens.
Available accessories include a battery grip (BG-E18), numerous viewfinder knick-knacks, and wired and wireless remotes. Both cameras will be available in April.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:22 PM | Message # 3
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Body & DesignRebel T6s / EOS 760DRebel T6i / EOS 750DThe design of the Rebel T6s is very similar to it's sibling, the T6i. We present both here so that you can make a visual comparison between the two.In general, the design of the Rebel T6s (760D) adheres close to the norm set by 2013's T5i (700D). The main differences are on the top plate, as you'll see in a minute. The T6s is a compact DSLR with an aluminum alloy and polycarbonate chassis and a composite shell. While it doesn't feel as solid as, say, the EOS 70D, the T6s don't feel cheap. As with earlier Canon DSLRs in this class, the grip on this model may be too small for those with larger hands.
On the front of the cameras you'll find an IR receiver, AF-assist lamp, and stereo microphone. On the left you'll see the SD card slot, while the I/O ports sit on the opposite side. The back of the T6s is loaded with buttons, and also includes a 'quick control' thumb dial in addition to the standard control near the shutter release.
If you want a more complete look at the T6s, try our new 360-degree view:
 
NguyenHoangDate: Thursday, 2017-04-13, 3:23 PM | Message # 4
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In your hand
In this photo of the 760D you can see just how compact it is. It's close in size to the Nikon D5500 but not quite as large as the Canon EOS 70D or Nikon's D7100. With one of Canon's smaller primes attached, you can practically carry the T6s in a purse or small bag.
Body elementsThe T6s has an all-new 24MP CMOS sensor, up from 18MP on every Rebel since the T3i.

It also uses Canon's EF-S mount, which is designed for APS-C-size sensors. Don't worry, your regular EF lenses will work too. 

The crop factor on this and all Canon APS-C cameras is 1.6x.It also has a pop-up flash with a guide number of 12 meters at ISO 100. 

You can use this flash to control multiple Canon EX Speedlites, if you wish.

The flash also serves as the camera's AF-assist lamp, which means that it must be popped up in order to use that feature.As with the T5i (700D) before, the T6s (760D) has a fully articulating 3" LCD with 1.04M dots.

The display is touch-sensitive and allows for focusing, picture-taking, menu operation, and image playback.The viewfinder has 95% coverage and a magnification of 0.82x. 

The T6s also has an eye sensor, which turns off whatever is on the LCD.The T6s has jacks for A/V out, HDMI (of the mini variety), an external mic, and a wired remote control.The T6s uses the new LP-E17 lithium-ion battery. You can take 440 shots (CIPA) per charge while using the optical viewfinder.

If you're using live view full-time then expect just 180 shots per charge.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:23 PM | Message # 5
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Shooting ExperienceBy Dale BaskinThe original Canon EOS Digital Rebel holds a special place in history for many photographers. It was the first digital SLR to cost less than $1,000, and became the portal through which many photographers were able to experience serious digital photography for the first time. As a photographer who was inspired by that original Rebel myself, I was excited to try out the newest generation of the series to see how the Rebel has evolved over the past 12 years.
Two RebelsOf course, this time Canon threw us a loop and introduced not one, but two, new Rebels. Although there are a few differences in physical layout and features, at their core both 'T6' Rebels are different flavors of the same camera, built around a new Canon-designed 24.2MP CMOS sensor.
Side by side, it's virtually impossible to tell the T6i apart from its predecessor, the T5i. The only obvious difference is the addition of two buttons: the AF Area selection button and the Display button (which toggles the LCD on and off). Suffice it to say, if you've shot with the T5i (or the T4i, T3i, etc.) you should feel right at home on the T6i.
Despite a handful of design differences, the T6s and T6i are built around the same imaging sensor and AF system.In contrast, the T6s seems to inherit some of its DNA from the enthusiast-oriented EOS 70D, including a top plate LCD screen, a mode dial repositioned to the left side of the camera, and most notably the addition of a rear thumb wheel in place of directional buttons. While it may be tempting to look at the T6s and think of it as a 'baby 70D', it lacks the build quality and some of the important features of that higher end camera.
So, do the differences between the two T6 bodies actually have a real world impact on the shooting experience? Read on to find out.
Build Quality and ErgonomicsThe T6i and T6s have typical EOS Rebel build quality. Their largely polycarbonate bodies won't be mistaken for pro level equipment, but they nevertheless feel solid in your hand. Ergonomically, the two cameras are similar to previous Rebels. Most controls are well positioned and within easy reach (with one notable exception I discuss below). Basically, if you've picked up any of the recent generations of Rebels you have a pretty good baseline for how it's going to feel in your hand.
One characteristic of Canon's Rebels that I've never really cared for, and which continues on the T6 models, is the rather minimalist grip, which is narrow and not very deep. One could argue that it's difficult to build a good grip on a camera body this small, except that other manufacturers have done it; by comparison, the grip on the similarly sized Nikon D5500 feels much more comfortable and secure in my hands.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:24 PM | Message # 6
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HandlingYou won't notice a lot of differences between the T6s and T6i just by holding them in your hands. However, the differences become more pronounced once you start shooting, as I discovered when I headed off to Seattle's famous Pike Place Market with both cameras in my pack.
One of the challenges of shooting at the market is the sometimes tricky lighting, due to the indoor/outdoor nature of the place. It's a location where I constantly use exposure compensation to bump exposure up or down a bit as conditions dictate.
I wanted to bring up the shadows in this image a bit, so I added +1/3 stop of exposure compensation on the T6i.The T6i follows the 'classic' Rebel approach for setting exposure compensation: reach over and press the exposure comp button with your thumb, then make EV adjustments with the control dial. It's a two step process that makes redundant use of one control, but it works. Looking at the two cameras sitting on my desk, I decided in advance that I would prefer using the T6s due to the thumb wheel on the back, though this turned out to be only partially true.
The thumb wheel on the T6s is located fairly low on the back of the camera, and I found that I always needed to twist my hand in an awkward way to reach it. To be fair, this is one of those things that will vary person to person, depending on the size of your hands, how you hold the camera, and potentially other factors, so your mileage may vary.
The Rebel T6s gets a thumb wheel with integrated four-way controller instead of the T6i's standard buttons. It's a nice addition, though it's placement low on the back of the camera may be awkward for some people to reach.The wheel also doubles as a four way controller on the back of the camera. In a nice design move, the eye sensor above the viewfinder on the T6s disables the buttons under the wheel when you use the optical viewfinder to avoid accidental menu selections.
Overall, the thumb wheel is a nice addition to the T6s, but given its placement and small size it may not appeal to everyone.
It was also helpful to have the top plate LCD on the T6s. It definitely makes it easier to look down and see your settings at a glance, though all the same information can be displayed on the rear LCD if you want to get by without it.
AutofocusAfter several generations of using the same 9 point 'red dot' focusing system, the Rebel line inherits Canon's 19 point, all cross type, AF system. It's essentially the same system that first appeared in the EOS 7D and which is also used in the more recent 70D.
This AF system may not be groundbreaking by today's standards, but it performs quickly and without hesitation, even in low light conditions that called for shooting at ISO 12,800 and F2.8. In addition to performance improvements over previous Rebels, the updated AF system also supports zone focusing.
The T6s and T6i focus better in low light than previous Rebels thanks to their updated AF system. I shot this drummer and his dog in very dim conditions at ISO 12,800.Previous Rebels had two basic AF modes: automatic or manual AF point selection. The new 19 point system adds the ability to assign focus to one of five zones. This is a useful addition and I found it helpful for certain types of shots, particularly when I was trying to shoot a moving subject such as an approaching cyclist or a pet that moved a bit fast to keep under a single AF point.
Switching between focus modes is quick and easy, thanks to the new AF Area selection button located near the control dial on both cameras. Pressing the button cycles through focusing modes and the rear four-way controller can be used to select your desired AF point or zone. As with other EOS bodies, you can change your selected AF point on the fly using the AF point selection button on the right shoulder of the camera.
Another important addition to the Rebels' focus system is a 7,560 pixel RGB + IR metering sensor for more accurate metering. To be clear, this is nothing like the 150,000 pixel sensor on the 7D Mark II, nor do the Rebels claim to support face detection or Canon's iTR (intelligent recognition and tracking). However, the metering sensor does support 'color tone detection', which should allow the camera to at least identify and focus on skin tones.
I found 'color tone detection' to work fairly effectively when using One Shot or AI focus and automatic AF point selection enabled. In most cases the system did a good job of identifying and focusing on people. Unfortunately, in One Shot mode there's no ability to track the subject, so if your subject moves you need to refocus.
The RGB + IR metering sensor in the Rebel T6s and T6i uses 'color tone detection' to help identify skin tones in the scene, however it lacks Canon's iTR (intelligent tracking and recognition) technology which helps identify patterns and faces. In the photo above, you can see that the AF system focused on Dan's hand even though his face is clearly visible in the center of the photo.If you really want to track moving subjects you'll need to switch to AI Servo focus mode. In AI Servo you initiate focus with a single AF point and the system tries to track your subject by automatically selecting AF points to stay on top of it anywhere in the frame. I found this to be very hit or miss, even with well isolated subjects. At best the AF system would stay on the subject around 50% of the time, and mostly when it moved slowly.
As I noted above, the Rebels don't include Canon's iTR system for subject tracking, however one might have expected some rudimentary subject tracking due to the presence of the RGB + IR metering sensor. Instead, the cameras appear to only use depth information to track subjects across the frame, which offers limited success. As a result, you may be better off just turning off tracking and using a single AF point or zone to track your subject.
This is disappointing as cameras in the Rebels' peer group do a much better job in this department. The Nikon D5500, for example, employs Nikon's 3D tracking and does an impressive job of tracking subjects in the optical viewfinder. Similarly, mirrorless ILCs such as the Sony A6000 do a good job of subject tracking as well, so I was disappointed that Canon still lags in this area.
While reviewing my images after a few days of shooting I uncovered one problem that I hadn't noticed while viewing images in camera. A couple of the lenses I used were front focusing, particularly the 70-200mm F2.8L, on the T6s. You can see this in the photo of the sailboat below. The AF points were right on top of the sail, but if you look at the full size image the plane of focus appears in front of the boat. This behavior was consistent and showed up in almost every shot I took of the sailboats.
In this photo taken with the Canon 70-200 F2.8 IS L lens the autofocus points were right on top of the sail, but on closer inspection the plane of focus appears to be in front of the boat in the water.Unfortunately, the Rebels don't offer the ability to perform AF microadjustments, so there's really no way to correct for this short of sending your equipment to Canon for calibration. (For the record, the Nikon D5500 doesn't support microadjustments either.) The cynic inside me wants to pass this off as a limitation of entry level cameras. After all, the thinking goes, most people who buy this camera will probably only ever use a kit lens and shoot at F5.6 or smaller, so they will never run into this problem.
While there may be some truth to this logic, I don't think this gives enough credit to consumers. I've known plenty of enthusiasts, and even pros, who use Rebels for various purposes, and the inability to perform microadjustments is a significant handicap. In fact, this is one area where mirrorless cameras have a distinct advantage over entry level DSLRs as they generally don't suffer from AF accuracy issues.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:24 PM | Message # 7
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Auto ISOBoth Rebels support Auto ISO, but the implementation doesn't offer much flexibility. Basically, your only option is to select the maximum ISO you want the camera to shoot at.
With Auto ISO enabled I was frustrated by the camera's insistence on using the absolute slowest shutter speed possible for any given lens. The system seems to follow the one over focal length rule of thumb, so it's aware of what focal length you're shooting at, but I often wished that I could get it to shoot at a higher shutter speed in aperture priority mode.
Auto ISO on the Rebels works well, but both cameras lack advanced settings such as the ability to specify a minimum shutter speed. As a result, almost all images shot using Auto ISO in aperture priority mode will use the lowest recommended shutter speed for the focal length being used, down to 1/30 sec.By way of example, when shooting with the EF-S 24mm F2.8 STM lens I was pretty much relegated to shooting at 1/30 sec in aperture priority mode (except for the occasional shot where I was generously granted a shutter speed of 1/40 sec). Unfortunately, that's a bit slow for many real world situations such as a parent trying to photograph moving kids. I would have been happy to let the ISO creep up a bit in exchange for faster shutter speeds, but there's no mechanism to do that. As a result I often found myself using manual ISO.
An alternative would have been to shoot in M mode with Auto ISO, where I could select both the shutter speed and aperture. Unfortunately though, the Rebels don't support exposure compensation via auto ISO in M mode, so I have no control over image brightness shooting this way.
Live ViewThere aren't a lot of surprises when it comes to live view shooting. Both cameras have touch screens with the usual array of features, including tap-to-shoot functionality. The big improvement from previous models is the inclusion of Canon's Hybrid CMOS AF III focusing system, which includes more sensor-based phase detection AF points than previous Rebel iterations. Canon claims the AF system's performance should be close, but not quite up, to cameras using its dual-pixel AF system.
I think Canon's claim is reasonably accurate. Live view focus is not quite as buttery smooth and natural as on Canon bodies with dual-pixel autofocus, such as the EOS 70D and 7DII. However, AF is generally more pleasing than on systems that rely only on contrast detect autofocus. The Rebels still have a tendency to ratchet focus a bit at the last moment before focus is achieved - a common side effect of contrast detect AF systems. While this will affect continuous shooting, stills of moving subjects, and video shooting, the implementation is still quite usable.
One AF feature worth calling out is subject tracking. When shooting in live view, both Rebels offer face detection as well as a tap-to-track feature that draws a box around your desired subject. It works really well. Find a face or tap a subject and the AF system sticks to it like glue. Not only is it better than the T5i, but it's at least as good, and possibly better, than the same feature on the relatively recent EOS 7D II. Subject tracking may not work well when using the Rebels' optical viewfinders, but live view is a different story.
For this photo of the fire dancer I placed the T6s on a tripod and pre-focused the camera on him in live view before he started dancing.Where the two cameras differ significantly in live view is support for AI Servo focusing, which is included on the T6s but not the T6i. This has a very real impact on how well live view shooting works. On the T6i the camera tries to keep the subject in focus, however when the shutter button is pressed the camera needs to reconfirm focus before taking the shot. This means that by the time the camera has actually taken the photo, your subject may have moved. Basically, live view focusing doesn't really work for moving subjects on the T6i.
In contrast, the T6s offers a very different experience. Thanks to AI Servo focusing the T6s has much better subject tracking than the T6i. Since it keeps your subject in focus the camera is ready to shoot right away when you press the shutter button. It's much more useful, and in fact may be the most compelling difference between the two cameras. If I planned to use live view often, particularly for moving subjects such as kids, this feature alone would steer me to the T6s.
Finally, its worth noting that unlike the 7D II and other Canon bodies, the Rebels' screens don't black out during continuous shooting in live view. Instead, the camera shows the last shot frame before returning to a live feed. There's still a pause every time a photo is taken in live view, but I'm glad to see this change.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:24 PM | Message # 8
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Image QualityLet me preface this section to set expectations. Undoubtedly, the biggest question on a lot of people's minds regards the performance of the new 24.2MP Canon sensor. Everything included in this Shooting Experience article is a purely subjective overview of what I've seen following several days of shooting. Make sure to look at our Studio Test Scene for a detailed objective analysis of the Rebel's image quality.
In general, I'm happy with the images from this camera; they have the pleasing color and natural skin tones that I'm used to seeing from Canon cameras. As expected, they deliver more resolution than previous Rebels, and this this additional resolution finally brings them on par with mid-range APS-C cameras from the likes of Nikon, Sony, and Pentax.
The Rebel T6s and T6i deliver pleasing colors and natural skin tones.Despite the increased resolution, the new sensor subjectively outperforms the 18MP sensors that have been the mainstay of the Rebel line for many years. In fact, from a noise perspective the Rebels appear competitive with similar 24MP APS-C models from other manufacturers, even at high ISO. They may not be quite as good as the class leaders, but there's not a lot of difference when looking at Raw files.
OK, I can practically hear the voices screaming by now. "Dynamic range! Just tell us about dynamic range!!!"
You'll have to read our Dynamic Range Lab Report for a truly objective analysis of dynamic range, but for anyone hoping that these new sensors would be Canon's answer to Sony's excellent dynamic range sensors, you're probably going to be disappointed. However, based on informal image comparisons it does appear that Canon is continuing to make small, incremental improvements to the DR of their sensors, so at least the trend is moving in the right direction.
Out of camera JPEGAdobe Camera RawThe photo I took of this fish stand at the market was significantly underexposed. I was able to recover quite a bit of detail in Adobe Camera Raw by increasing exposure 2.3 stops and adding +66 to the shadowsFinal ThoughtsI didn't expect a lot of surprises on these cameras, and I didn't get any. The Rebel series has has been a reliable bookend to Canon's EOS line of cameras for many years. Each new model tends to involve more evolution than revolution, most of which is understandably reserved for Canon's more advanced cameras. That said, they bring some nice additions to the series.
Most notable is the additional resolution from the 24.2 MP sensor. While it may not have the dynamic range we've come to expect (and desire) from recent Sony sensors, the new Canon is capable of providing very nice results. Even with the additional resolution, overall image quality appears to be an improvement compared to previous Rebels.
The biggest question some people may have is which Rebel to get. From a practical standpoint there's not a lot of difference between them, but in my opinion two things stand out.
The first is whether you prefer to adjust settings on the fly with buttons or a thumb wheel. I generally prefer a thumb wheel, but the awkward position of the wheel on the T6s (awkward for me, at least) made this choice a bit less obvious. This is one where you may need to try it out in person to know for sure.
Second, if you plan to do a lot of live view shooting the T6s is the obvious choice thanks to its support for Servo AF in live view mode. It speeds up shooting by keeping your subject in focus, doesn't require the camera to reconfirm focus on every shot, and is much more pleasant to use. In fact, this may be the single biggest reason to choose the T6s over the T6i. If it's a feature you'll use, it's easily worth the extra money.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:25 PM | Message # 9
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Viewfinder shootingThe optical viewfinder on the T6s has a magnification of 0.82x, which on an APS-C camera makes for a somewhat small viewing image. While this is similar to previous Rebel models, small optical viewfinders are starting to feel a bit dated. Maybe we've been spoiled by all the large, high quality EVFs to come across our desks in recent years, but the T6s viewfinder feels a bit smallish nonetheless.
The good news is that with the T6s (and its sibling, the T6i) Canon has finally updated the basic 9-point AF system that has been a staple of the Rebel line for years with a 'new' 19-point, all cross-type AF system. We call it 'new' because, despite the fact that it's new on the Rebel T6s, it's not a new system for Canon. In fact, this basic AF system was first introduced in the EOS 7D in 2009. While not cutting edge by today's standards, it has performed well on past models and brings some welcome improvement to the Rebel line.
The 19-point, all cross-type AF system on the Rebel T6s (and T6i) is a noticeable improvement over previous Rebels.One of those improvements is that there are now three AF point selection options: manual point selection, automatic selection, and zone selection. Zone AF allows you to select one of five AF zones (center, left, right, top, or bottom) and can be useful for some types of shooting, such as keeping AF points on top of a moving subject.
One thing to note: auto AF point selection, which is something we'd expect many typical Rebel users to wish to default to, is oddly implemented in continuous AF (AI servo). Previous Rebels would allow continuous AF with the camera automatically picking the starting AF point, but on the T6s, you must start with one AF point over your subject, after which the camera will automatically track your subject by choosing the appropriate AF points to remain on your subject as it moves.
While this is fine for a lot of users, it would've made sense to offer a mode where the camera can automatically select the AF point from the get-go, using skin-tone detection to focus on a human subject, for example (more on this later). As it is, if you want continuous AF and wish the camera to worry about focus point selection, you'll have to use AI Focus. And we found AI Focus - which tries to automatically decide if you have a moving subject that requires continuous AF - is very laggy in realizing your subject's actually moving. This means that quite often your subject will have moved quite a bit before your camera even realizes it should attempt to refocus. For moving subjects, you're better off selecting your own AF point (manual selection), and keeping it over your subject by constantly reframing, especially as 'auto selection' in continuous AF can be unreliable as we explain below.
Continuous AF performanceContinuous, intelligent AF performance to understand what it is you wish to focus on, and then reliably focus on that subject (even if it's moving), are features being increasingly offered in cameras these days. One might argue such features are especially important for the demographic using cameras like the Rebel - first time parents and first time shooters generally may not wish to take full control over focus, rather expecting that getting a DSLR should mean that the camera should just focus on their running child. This requires intelligent subject recognition, and good continuous AF performance, so we look at these in-depth below.
 
NguyenHoangDate: Thursday, 2017-04-13, 3:25 PM | Message # 10
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Real world trackingWe'll first start with a real world example of something that should be relatively straightforward for a modern AF system: an approaching subject well isolated with respect to depth (there aren't many other moving objects at a similar distance that might otherwise distract the AF system), that doesn't move too much from side-to-side.
Let's start off by saying that simple distance or depth tracking of subjects - e.g. subjects moving toward or away from you - tends to work very well on cameras with dedicated phase-detect systems, and here the Rebel T6s is no exception. Even when shooting at the maximum fps burst rate, the camera generally kept up with subjects moving toward or away from the camera. But our cycling example below tests a little more than that - we let the camera automatically select AF points to stay on the initially chosen subject (Richard on a bike). In the sequence below, while the T6s generally kept up with the subject, a good 6 shots or so are not optimally focused. Since the camera's depth tracking abilities are very good, what went wrong here?
1
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v
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While the highlighted AF points indicate the camera ostensibly stayed with the subject, there were instances in our multiple runs where the AF points wandered off. In other words, the subject tracking system is sometimes easily confused. The out-of-focus shots in the example above likely have less to do with the depth-tracking capabilities of the camera, and more to do with its ability to know what exactly to continue focusing on.
And how does the T6s know what to continue focusing on in AI Servo? The phase-detect AF module knows the distance of your subject initially when you half-press the shutter button, after which the system selects any AF point that reports a subject with similar distance (it's a bit more complicated, as the system also looks for contiguous movement across points, and any distance patterns indicating approaching or receding subjects). You might imagine that such a system might be easily tripped up by other nearby objects entering or leaving the scene, and might not have enough accuracy to differentiate Richard's face from his jersey from his bike handlebars (none of which are at drastically different distances from the camera). And you'd be right - a more advanced subject tracking system can use more information, like actual color or pattern recognition of a subject, to understand and stick with it.
In fact, it's likely the better subject tracking performance of the Nikon D5500's '3D tracking' system, which uses information from its 2,016-pixel RGB metering sensor to understand and stick to your subject, that gave it better performance in our similar test with that camera. This raises the question: what sort of subject recognition and tracking capabilities does the Rebel T6s have?
Subject recognition and trackingThese days mirrorless cameras offer sophisticated subject recognition by, for example, recognizing the nearest face and tracking it, no matter where that face ends up in the frame after subject, or camera, movement. DSLRs have traditionally struggled in this regard, as they don't have the advantage of an image sensor to constantly analyze during through-the-viewfinder shooting. DSLRs have, though, traditionally always sent a portion of the incoming light to a multi-zone metering sensor for accurate exposure. Recently, in some DSLRs, these metering sensors have seen a transition to full color, RGB array sensors - much like image sensors themselves - that can help analyze the scene and understand the subject for better tracking (and metering). Amongst DSLRs, Nikon offers the most accurate subject tracking we've seen to date, across most of their lineup. Canon hasn't been sitting still, though, and has made similar attempts with their metering sensors in the 1D X, 7D Mark II, and 5DS.
Some of that technology now filters down in limited form to the Rebel T6s, which sees the addition of a 7,560 pixel RGB+IR metering sensor. The implementation of the RGB+IR metering sensor on the T6s is a bit less sophisticated than on some other cameras, however. Instead of supporting face detection or pattern recognition for subject tracking, the T6s uses 'color tone detection' only to help initially select an AF point. In essence, it's designed to identify skin tones, making the assumption that skin tones probably represent the most likely target in any particular scene. While it does a reasonably good job of identifying subjects, skin tone detection can be fooled. In the shot of Dan from our shooting experience you can see how the camera focused on his hand instead of his face, assuming that the closest subject with skin tone was the desired subject.
Unfortunately, color tone detection only works in a narrow set of circumstances: shooting in one shot or AI Focus (not in AI Servo) with automatic AF point selection turned on. It doesn't use color, or the metering sensor, at all to track a subject once it starts moving, instead relying primarily on depth information to understand where your moving subject is in the frame (like the 7D/70D). Without pattern recognition or face detection, subject tracking tends to be pretty hit or miss on the T6s, as we demonstrate in the video below. It can work somewhat well when you have a subject well isolated with respect to depth (like our cycling example above), but is ultimately generally speaking unreliable enough that you're probably not going to want to trust it over simply selecting an AF point (or zone) yourself and reframing to stay on your moving subject.
 
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