Camera features and accessories

What is mirror lockup?

Nearly all SLRs use a flip-up mirror mechanism. When you take a photo the mirror flips up out of the way to expose the film or digital image sensor. Unfortunately this mirror motion induces slight vibrations in the camera, which can result in slight blurring appearing in the photo, particularly with extremely long telephoto lenses. Cameras contain foam bumpers to reduce this mirror slap, but some vibration is inevitable in a moving reflex mirror camera.

The simple solution to avoid blur caused by mirror slap is to flip up the mirror, wait at least a second or two to let the vibrations die down and then take the photo. There are two basic ways that cameras can do this.

Some cameras offer true mirror lockup. Such cameras let you flip up the mirror whenever you like. They may be purely mechanical mirror lock mechanisms or they may be electro-mechanical. Most of Canon’s high-end cameras offer true mirror lockup.

Other cameras offer what’s often known as mirror pre-fire. These cameras flip up the mirror a couple of seconds before taking the picture when the camera is in self-timer mode but don’t let you lock up the mirror at will. Most of Canon’s midrange cameras offer mirror prefire in conjunction with the self-timer or an infrared remote control.

Obviously there’s a significant drawback to mirror lockup - you can’t look through the viewfinder when the mirror is locked up. For that reason mirror lockup is really only used in slow-paced picture-taking conditions, such as landscape photography when using a tripod, and so on. Canon are also notorious for hiding mirror lockup or prefire access in the camera custom function area, which makes it inconvenient and slow to access. (unless your camera has a C mode on the command dial) However, don’t worry unduly if your camera lacks the feature. For most applications it doesn’t make a massive difference in camera blurring, and Canon cameras have fairly well-damped mirrors.

What is a pellicle mirror?

As noted above, most SLRs contain moving reflex mirrors which flip up to let light from the lens expose the surface of the film or the digital image sensor. However some SLRs use fixed mirrors instead. Canon have made a number of such cameras over the years - the EOS RT and EOS 1N RS being the most recent models.

These cameras have “pellicle” mirrors which are essentially fixed half-silvered mirrors which send some light up to the viewfinder while passing the rest through to the shutter. The result is a camera which can shoot instantly with no mirror blackout time - perfect for sports and action photography - and no need for mirror lockup. The drawbacks are less light reaching the film, a dimmer viewfinder and the need to keep the mirror scrupulously clean at all times. Such cameras are fairly specialized pieces of equipment and not used by most photographers.

What is meant by a bright or dim viewfinder?

Very simply this refers to the amount of light reaching your eye when you look through the camera’s viewfinder. High-end Canon cameras tend to have very bright and clear viewfinders. Cheaper Canon cameras tend to have dimmer viewfinders, almost as if a brightness knob has been turned down.
Obviously bright viewfinders are better than dim ones, as they make it easier to see your scene for focussing and composing. Unfortunately, bright viewfinders also require large glass pentaprisms (see below). Canon’s cheaper cameras have either smaller prisms or roof mirror systems.

What is a pentaprism? A roof mirror?

The key feature of the SLR camera is the ability for the photographer to look through the viewfinder and see directly out of the taking lens, and a clever optical trick is required to make this possible. The traditional approach is to use a large solid glass prism to reflect incoming light from the lens and project it up into the viewfinder. This prism is known as a pentaprism because it has five sides through which light passes or is reflected. The pentaprism is also the reason why SLR cameras have large angular humps on the top.

While it may seem obvious today, the pentaprism was quite a breakthrough when it was introduced with the 1949 Contax S camera. Before the advent of the pentaprism, camera viewfinders usually displayed laterally reversed and/or upside-down images.

While pentaprisms work quite well there is one drawback associated with them - they’re solid blocks of heavy and expensive optical glass. For that reason Canon, starting with the Rebel X/EOS 500 series of cameras, began putting hollow mirror systems into their consumer EOS cameras rather than pentaprisms. This has the advantage of making the camera considerably lighter in weight and lower in profile, but also has the drawback of creating a dimmer viewfinder, since mirrors are less efficient at reflecting light than prisms.

What is a viewfinder shutter or cover for?

High-end Canon SLRs have a flip-down lever by the viewfinder that lets a mechanical shutter swing down and physically cover off the back of the viewfinder so you can’t look through it anymore. Canon SLRs which lack this feature usually ship with a detachable plastic or rubber cover either attached or built into the camera strap.

What’s this for? Well, the light metering sensors in an SLR are located inside the top hump of the camera as part of the viewfinder assembly. They record light levels inside the viewfinder. And when you’re peering through the viewfinder then most of the light entering the camera is coming in through the lens. However, when you’re not looking through the viewfinder (thereby physically blocking it) then light can enter the camera from the viewfinder itself, throwing off the light meter. This is particularly a problem if you’re using the camera on a tripod in self-timer mode.

Viewfinder shutters, therefore, reduce the risk of metering error from stray light entering the viewfinder. So they’re only useful in automated exposure modes. If you’re shooting in manual metering mode then the shutter isn’t needed since it’s you, not the camera, who’s setting both shutter speed and aperture. Note that there’s no risk of this stray light affecting the film or image sensor at all - it can’t make its way past the flipped-up mirror. It only affects metering.

Of course you can use anything on hand to block this stray light if you lose the viewfinder cover. You could put a hat over the back of the camera, say. Kodak’s black 35mm film canister lids fit neatly over a lot of EOS camera viewfinders as well, though Fuji’s don’t (partly because they’re translucent white and partly because they don’t fit).

What is dioptric correction?

Many people who wear glasses don’t like wearing them when they look through the viewfinder. The glass bumps up against the eyecup, so you can’t get your eyes close to the viewfinder. This makes it hard to see the entire image, particularly with EOS cameras which are notorious for not having the greatest viewfinders in this regard.

But obviously if your eyes require corrective lenses then you won’t be able to look through the viewfinder if you take your glasses off. At least not if you couldn’t adjust the focus of the viewfinder itself. This is what dioptric correction does - it lets you adjust the viewfinder so that spectacles-wearing photographers can see through it sans glasses. Cameras with built-in dioptric correction have tiny dials or sliders located next to the viewfinder. Moving these controls adjust the viewfinder focus point.

Note that you aren’t out of luck if your camera lacks such correction facilities and you want it. Canon sell small add-on lenses which clip directly onto the viewfinder of most EOS models. These dioptres are available in a variety of strengths to suit different eye prescriptions.

Personally, as a glasses-wearing person, I don’t find dioptric adjustment very useful. I’d be much happier if Canon cameras would simply accommodate eyeglasses wearers better by altering the exit pupil of the viewfinder such that you don’t have to jam your face right up against the viewfinder to see everything. Dioptric correction means that you have to take your glasses off to look in the camera, put them back on to see the world, take them off again, etc. Still, many people do find dioptric adjustment very useful. You’re probably best off trying the camera in a shop to see what works best for you.

What is depth of field preview?

When you look through the viewfinder of a Canon EOS camera - or just about any modern SLR - you’re looking through the lens when the aperture is set to its widest setting. This means as much light as possible is coming through, which makes it easier to see the scene and focus and so on.
However, depth of field is at its shallowest when the lens is wide open. So if you want to get a sense of the depth of field that will result from some other aperture setting you need to close the lens down physically to that setting. The depth of field preview button available on most Canon EOS cameras does just this.

Unfortunately the differences in depth of field between various settings can be hard to make out in the viewfinder itself. So all the DOF preview button usually does is to make things look darker. And if you’re shooting in low light conditions, making the viewfinder darker may mean you can hardly see anything at all. So DOF preview buttons, while they have their uses, are of somewhat limited value.

What is eye-control focus (ECF)?

Eye-control focus is a technology unique to Canon that lets the camera track what you’re looking at in the viewfinder so it can select the nearest focus point automatically.

ECF works as follows. A series of tiny infrared LEDs (light emitting diodes) shine harmless infrared energy onto your eyeball as you peer through the viewfinder. Light sensors record the infrared reflecting off your eye and calculate the focus point. A computer in the camera then examines this data and decides which of the focus points is closest to that point and selects it. If the camera is in AI Servo mode then it will also adjust focus automatically based on that selected point.

ECF is thus a very complex technology which involves a lot of different factors. And, needless to say, it works well for some people and not well at all for others. Each ECF-capable camera must be calibrated for each user, but even thorough calibration (you need to run through calibration at least a half dozen times or more before things will be set up properly) is no guarantee that ECF will necessarily work for a given person. Reliability of ECF depends also on the speed of the eye scanner. The EOS A2E/5, the first cameras to use ECF, were fairly slow at selecting the correct focus point. The EOS 3 and the Elan 7E/EOS 30/7, by contrast, have faster computers and so respond more quickly. Interestingly, the 1V (Canon’s top of the line film camera) does not support ECF. Canon have stated that this is because they wanted the 1V to work 100% of the time, and that ECF does not attain that level of reliability.

Some people use ECF a lot and consider it a very useful feature; almost magic. (look at something and it goes in focus!) Others find it a pointless gimmick that doesn’t work reliably. At time of writing Canon have not released any digital cameras with the feature, so it’s unclear what its future is.

What is a cross sensor?

There are two basic configurations of autofocus sensors used in SLR cameras. Linear sensors detect lines in one direction only - usually just vertical lines, though some camera sensors, such as the EOS 10/10s outer sensors, can detect only horizontal lines. Others, known as cross or cross-shaped sensors, can detect both vertical and horizontal lines. With their higher sensitivity, cross sensors are considerably more accurate than linear sensors, particularly in lower-light conditions. Some cross sensors are also high-precision sensors (see below).

Most EOS cameras with multiple focus points have a cross sensor as the central point and vertical-line sensors as the other points. So in challenging focus situations it’s usually best to switch manually to the centre sensor so you get the full benefits of the cross. Note that the first generation of EOS cameras (600 series) and most early Rebel/three or four digit film cameras do not have cross sensors.

Autofocus doesn’t work very well when it’s dark. What can I do?

Low-light autofocus is quite a challenge for any camera that uses a passive autofocus system, like all EOS cameras. Passive autofocus means that the camera simply looks through the lens and reads whatever’s there - it doesn’t send out infrared or sound or light or radar beams or whatever to determine the correct focus distance. (the AF assist systems used by most Canon cameras and flash units don’t change this, since the lights are optional assist systems and are not required by the autofocus system)

Generally speaking the more expensive the camera the better the autofocus. There are exceptions to this, but it’s a reasonably accurate predictor of how good AF is going to be when light levels are lower. So a top of the line EOS 1V is going to have wildly better low-light autofocus than an old EOS 1000 consumer camera, for example. This doesn’t quite apply with digital cameras, though - the D30 and D60 are both more expensive than roughly comparable film cameras, but have very poor low-light autofocus.

One way to get a sense of the camera’s low-light AF performance is to look at its specifications. Light levels for AF systems are measured in exposure values (EV), and autofocus systems have their light sensitivity levels expressed as a range of EV. A good camera can autofocus from 0-20 EV. A consumer camera can usually only manage 2-20EV, which means that it needs more light at the dimmer end of the scale to work properly.

Unfortunately low-light AF performance is one area where Nikon products are generally better than Canon products. Many Nikon products autofocus down to -1 EV, for example. Nonetheless there are several things you can do to help your camera with its low-light AF performance.

• The majority of EOS cameras with multiple focus sensors have a cross-type sensor as the central sensor. As noted above, cross-type sensors are more accurate than linear sensors because they can detect both horizontal and vertical lines rather than just lines in one direction. So always switch manually to your camera’s centre focus point for improved accuracy.

  There is one significant drawback to this approach which you should keep in mind, however. Canon E-TTL flash biases flash exposure to the selected autofocus point. So if you focus on something with the central focus point, recompose the image by moving the camera and then take a photo there’s a good chance that the flash metering will be out. In this case you should lock flash by using FEL prior to recomposing.

• Passive autofocus systems try to detect changes in contrast, so help your camera out by giving it a sharp line to focus on. Look for a wall or the edge of something where one side is brighter than the other and the two areas are sharply delineated. This, more than anything else, will make a tremendous difference. Don’t try to focus on a blank wall - AF systems have difficulty with featureless surfaces in bright light, let alone when it’s dark.
• Use an AF assist system. Many EOS cameras contain some sort of light-producing lamp which helps the autofocus system in low light conditions. The best kind of AF assist light is a bright red LED which projects a series of patterned lines. It’s relatively unobtrusive as AF assist goes, and the striped lines help the AF system lock focus. A number of cameras - notably the 10/10s, Elan/100, Elan II/50, 5/A2/A2E, Rebel S II/EOS 1000FN and others - have such red lights. Other cameras have white incandescent flashlight-type AF assist lights which work, though not as well. Others, such as the Rebel 2000/EOS 300, Elan 7/EOS 30/33/7, have no dedicated lights and simply emit stuttering pulses of light from the popup flash, which is extremely annoying. Whichever system your camera uses, however, see if it helps with autofocus. Note that some large lenses or lens hoods can block the light from body-integral AF assist lamps.
• Attach an external Speedlite flash unit. All Canon Speedlite flash units contain red AF assist lamps which can help autofocus considerably, especially if your camera hasn’t got one. There are a couple of limitations to keep in mind, however. First, two cameras - the 5/A2/A2E and the 10/10s - will not activate external Speedlite AF assist lights. Second, many flash units are not capable of a wide enough spread of their AF assist light beams and so cannot illuminate the outer autofocus points of multiple focus point cameras. Even those with the ability to cover all the focus points of your camera generally illuminate the centre point with lots of light and the outer points with less light. So again it’s best to stick with the centre AF point.
• Use a faster lens (ie: a lens with a smaller maximum aperture value). A lens with a maximum aperture of f/1.8 is going to autofocus in low light much more reliably than one with a maximum aperture of f/4.5, for the simple reason that the faster lens will let in many times more light.
• Try to focus manually. This is difficult if your camera has a simple matte focus screen. But if you’re lucky enough to have a focus screen with a split circle focus assist aid (see below) then it’s probably most reliable to focus manually.

Which EOS cameras can use split circle viewfinder screens?

Back in the 1960s and 70s microprism viewfinders were common in SLRs. These were special viewfinder screens containing tiny prisms on the surface. These prisms would break up the surface of out of focus areas, making it easier to focus. A later innovation was the split circle (split prism) viewfinder. Such viewfinder screens featured a circle, bisected by a usually horizontal line, in the centre of the screen. To focus the camera you would find a high-contrast vertical line (eg: edge of a wall, a tree trunk) and look at it through the viewfinder. You would then adjust the focus until the line appeared unbroken in the split circle. Split circles worked quite well, but had two notable drawbacks. First, you needed to find a straight line to focus on and second, the image in the circle tended to black out when used with very slow lenses. There were also combination viewfinders with split circles in the centre and a ring (collar) of microprisms.

Sadly, most camera makers ditched these convenient manual focus aids with the advent of autofocus in the late 1980s, apparently on the assumption that autofocus is so fabulous that you’ll never need to focus manually again. And worse yet, most EOS cameras do not have interchangeable focus screens.There are, therefore, only a handful of EOS camera models to which split circle viewfinder screens can be added. These cameras are listed below. All other EOS cameras cannot use a split-circle viewfinder.

The following cameras had or have interchangeable viewfinder screens, and Canon make or made a variety of optional screens for these cameras, including split circle screens. Some also have third party screens available from American makers; Reflexite Beattie Intenscreen being one and Brightscreen being another - though note that these makers do not necessarily support all of the cameras listed below.

EOS 600 series (650, 620, 600/630, RT), EOS 1 series (1, 1N, 1N RS, 1V, 1D, 1Ds, 1D mark II, 1Ds mark II, 1D mark IIN), EOS 3.

The following EOS cameras have interchangeable focus screens, but Canon never made a split circle screen for them. Not sure why - presumably because Canon never designed their metering systems to accommodate a split prism, which is a shame. The Beattie Intenscreens for Canon EOS cameras are Canon screens with Beattie’s custom coatings, so you can’t buy a split circle from them either. There are third party screens for the EOS 5D, however.

EOS 5/A2/A2E, EOS 5D

The following camera was not sold as an EOS camera, but was a stripped-down Rebel/1000 without the ability to autofocus. Since it was a manual focus camera it shipped with a split circle viewfinder:

EF-M

The following cameras do not have officially interchangeable viewfinder screens, but by happy coincidence have viewfinder screens of precisely the same size and dimensions as the long-discontinued EF-M (ie: they were all built around the same basic mirror box chassis design). As a result it’s fairly easy to remove the stock laser matte screen and replace it with an EF-M screen. For information on making this change have a look at my split circle screen page.

EOS Rebel/1000 series (EOS 1000, EOS 1000F, EOS 1000F QD, EOS Rebel, EOS Rebel S, EOS Rebel S Quartz Date, EOS 1000 QD, EOS 1000N, EOS 1000FN, EOS 1000FN QD, EOS Rebel II, EOS Rebel S II, EOS 1000S QD and EOS 1000S QDP), EOS 100/Elan. (possibly others)

The following digital cameras do not officially have interchangeable viewfinder screens according to Canon, but have third party focus screens available from two separate American entrepreneurs - Katz-Eye and Haoda Fu. These add-on screens give you a split-circle manual focus assist with, on some versions, a microprism collar. I have not tried the Katz-Eye products, but I have a review of a Fu viewfinder on this site.

EOS 10D, 20D, 300D/Digital Rebel/Kiss Digital, 350D/Digital Rebel XT/Kiss Digital N

How good are EOS cameras and lenses for manual focus work?

Frankly, not great. EOS cameras and lenses are both completely optimized for autofocus operation. You can go into manual-focus mode at any time (only a couple of really old cheap EF lenses lack manual focus rings) on any EOS camera, but it’s not always an easy thing.

First of all, EF lenses generally have very short throws, which makes precise focussing by hand fiddly. (this was done deliberately, since lenses with short throws can autofocus more quickly than those with long throws) Second, most EOS cameras do not have interchangeable finder screens and the screens that the cameras ship with lack any form of focussing aid, as mentioned in the previous section.

So if your priority is manual focus then the EOS system may not be the system for you. You should consider either an EOS camera with a split-circle focus aid (see above) or a different camera system.

What does it mean that Canon professional cameras are high-precision and optimized for fast lenses?

Canon’s high-end EOS cameras (1, 1N, 3, 1V, 1D, 1Ds, 1D mark II, 1Ds mark II, 5D) contain high-precision cross sensors. These are autofocus sensors which focus three times more accurately than the standard sensors found in other camera models. The drawback is that they require very fast lenses to work. If you put a slower lens onto one of these cameras then the cross sensors revert to linear sensors which detect lines in one direction only. The upshot is that putting a slow lens on one of these cameras is a bad idea as you’re not taking full advantage of its capabilities.

Is this a big deal? Should you be worried that your non-high-end EOS camera has only standard precision autofocus sensors? Well, if you’re shooting under conditions of very narrow depth of field all the time - extreme macro photography or really long telephoto lenses - then using a pro camera can help you autofocus more accurately. But if you’re doing normal photography then you probably won’t notice a difference.

What is the advantage of a rear control dial (QCD)? Why doesn’t mine work?

Most EOS midrange and pro cameras (from the EOS 100/Elan on and the EOS 1 on, respectively) have thumb-operated rotating dials on the back panel. These command dials are a very popular feature as they let you adjust both aperture and shutter speed with one hand when in manual mode and let you adjust exposure compensation in P, Tv and Av modes, again with one hand. This dial is also known as a QCD, or Quick Control Dial.

Cameras which lack this rear dial have a back-panel shift button. You have to press this button while rotating the main index-finger-operated dial to adjust the second function, which is considerably less convenient.

The 580EX flash unit also has such a rear control dial, which makes it easier and quicker to adjust flash exposure compensation and other functions.

If your camera has a rear control dial and it doesn’t seem to work it’s likely that it isn’t turned on. Most EOS cameras with rear dials have small on/off switches next to the dials which allow you to disable the dial so it doesn’t get nudged accidentally. Some EOS cameras have a three position power switch - off, on with the rear dial off, and on with the rear dial on.

What are add-on handgrips for?

Many EOS cameras can have optional handgrips added to their bases, and a few (notably 1-series digital cameras) have large handgrips permanently attached. These handgrips serve a number of different functions.

• Many add-on handgrips, such as the BG-E3 for the EOS 350D/Digital Rebel XT or the BG-E4 for the EOS 5D, can contain additional batteries for extended shoots. The most common battery grips can contain either two regular camera batteries (frequently disposable 2CR5 or rechargeable BP-51x, depending on whether they’re film or digital) or else a number of AA cells. The advantage of AA support is that AA cells are pretty well ubiquitous. If you find yourself in the middle of nowhere and run out of regular battery power there’s a good chance there’ll be a tourist giftshop or a grocery store nearby with AAs.
• Many handgrips, particularly those for midranged to advanced models, contain additional controls. The most common additional control is a second shutter release button to make shooting in portrait (vertical) configuration more comfortable and convenient. Studio photographers frequently use handgrips for this reason. Some grips also contain second control dials and other features. For example, the VG-10 Vertical Grip for the EOS 5/A2/A2E film cameras sports a shutter release button, a main dial, an AE lock button and an AF focusing point selection button, but oddly lacks additional batteries.
• Handgrips make the camera easier to grab and move for people with larger meatier hands, particularly when the camera is in portrait orientation.
• Some handgrips have attachment points making it easy to attach handstraps, for people who like carrying their cameras around in one hand rather than over one shoulder.
• Handgrips make the cameras big and impressive looking, which may appeal to some people. Conversely, of course, they can make the camera rather bulky and noticeable, which isn’t always a good thing.
• A handful of camera grips, such as the GR-60 for the EOS 10/10s or the GR-70 for the EOS 1000/Rebel, contain no additional features and are simply lumps of rubber. And one or two others contain unusual features, such the fold-out mini tripod in the GR-80TP grip for the EOS 500N/Rebel G. It all depends on the camera model.

What is the advantage of a removable camera back?

Certain EOS film cameras, mainly the high-end pro models, have interchangeable backs. This feature lets you remove the camera back which shipped with the camera and install a different back instead.

For example, you could swap your regular camera back out for one with more sophisticated timer functions, such as the Command Back E1 for EOS 1 and 1N cameras. Or you could add a Quartz Date Back E to an EOS 630 to get date printing. Professional photographers sometimes install Polaroid film backs so that they can get instant previews of complex lighting situations.

None of Canon’s current low or mid-range film cameras support interchangeable camera backs. None of the digital cameras have interchangeable backs for obvious reasons and neither are their electronics upgradeable.

Should I pay extra for a date back film camera?

Personally I don’t think that film date backs are a useful feature, because all Canon EOS 35mm cameras with date printing will print this information on the visible portion of the negative - in the lower right-hand corner of the final print or slide. This is great for identifying what day you took a snapshot or keeping track of research photos on an expedition, say, but it’s also really ugly-looking, as the print will obscure part of the image. And, just like VCRs with their flashing time displays, people always seem to forget how to change the clock and end with piles of photos with the wrong date or time on them.

Sadly no Canon EOS cameras have the ability to print the date between frames on the negative. Models with date capabilities are typically identified as “QD” (for Quartz Date) or “DATE” in the product name. EOS consumer cameras marketed in Japan, however, nearly all ship with date-printing as standard feature, as it’s apparently considered a desirable function there. You can, of course, turn date-printing off if you don’t want to use it.

The exceptions to this problem of printing dates on the image are Canon’s APS cameras and the digital cameras. APS cameras record date information to a magnetic strip on the film, so you can request the date be printed on the back side of the photograph when you have it developed. Digital cameras record the date and other shooting data along with each picture, but the data is stored separately (as EXIF data) and so does not appear on the actual image.

The only camera for which I recommend the date version is the Rebel Ti/EOS 300V/Kiss 5. For some reason the date version of this camera supports the optional wireless remote control, whereas the non-date version does not. So if you’re looking to get this camera I recommend the date version for that reason alone - wireless remotes are great.

Of course, if you think there might be a chance you’d want date printing then you should make sure your camera has the feature when you buy it. Aside from a handful of exceptions listed above, most EOS cameras do not have interchangeable backs, which means you can’t add date printing capabilities later on.

What types of remote controls are there?

Remote shutter releases are an essential part of every photographer’s toolkit. They let you take photos without touching the camera, which can be important if you’re using a tripod and want to avoid camera blur, particularly in bulb mode. And they let you trigger the camera at some distance from it.

All EOS cameras use either wired electric shutter releases (wires with simple pushbutton switches on the end) or wireless infrared shutter releases or both. The old style mechanical shutter releases (sort of like bicycle cables with plungers) are not supported, though if you really miss them you can buy the Canon Cable Release Adapter T3 (see below).

Canon have included three basic types of wired connectors with their EOS cameras over the years. This isn’t really a beginner question per se, but here for completeness:

T3 connectors.

The first EOS cameras, the 600 series, did not ship with shutter release sockets but had optional handgrips (GR-20 handgrips) which had plugs for shutter releases of the T3 variety. Several other EOS models of the late 80s and early 90s - notably the 1, 1N and 5/A2/A2E - shipped with T3 connectors built in. A few - notably the Elan/100, the 10/10s and the Rebel/1000 line - lacked support for any kind of wired shutter release at all.

T3 connectors are a proprietary electrical connector and are not supported by anyone but Canon. And sadly they’re fiddly and annoying to deal with, especially if you’re trying to fit a shutter release to your camera in the dark, as they’re tricky to thread on.

Cameras which have T3 connectors:

T90, EOS 650, 620, 630/600, (all EOS 600 series cameras require the GR-20 grip) 750, 850, 1, RT, 5/A2/A2E, 1N, 1NRS.

T3 accessories:

Remote Switch 60-T3 (or RS-60T3). A simple wired remote with a 60 cm cord.

Extension Cord ET-1000T3. A 10 metre (33 foot) extension cord for T3 releases.

Cable Release Adapter T3. A device with a switch on the end of a short length of cable which adapts old-style mechanical shutter releases to all EOS cameras with T3 wired connectors.

Remote Switch Adapter T3. An adapter cable for adapting old-style Canon TM-1 shutter releases (the kind used on really old manual-focus FD mount cameras) to T3-equipped cameras.

Wireless Controller Set LC-3. A staggeringly expensive wireless infrared shutter release system for T3-equipped cameras, consisting of a separate transmitter and receiver. 100 metre range.

2.5 mm miniplugs.

Most midrange EOS cameras since the mid 90s and consumer EOS cameras since the late 90s come with standard 2.5mm (3/32" in the USA) audio three-connector sockets for remote shutter releases. These connectors, named “E3” by Canon, are handy since they’re commonly available and thus homemade shutter releases (see below) can easily be made. You can also make an extension cord for this type of connector as well - just get a headset extension cord for a cellular phone which uses 2.5mm stereo plugs. The downside is that the tiny plugs are a little fragile and do not lock, which means they can come unplugged easily by mistake.

Cameras which use 2.5mm miniplugs:

EOS 50/50E/55/Elan II/IIE, EOS 30/33/7/Elan 7/Elan 7E, EOS 30V/33V/7S/Elan 7N/Elan 7EN, EOS 500/Rebel X/XS/Kiss, EOS 500N/Rebel G/New Kiss, EOS 5000/888, EOS 3000N, 66, Rebel XS N, EOS 300/Rebel 2000/Kiss III, Kiss IIIL, EOS 300V/Rebel Ti/Kiss 5, IX, IX 7, IX Lite, EOS 300D/Digital Rebel/Kiss Digital, EOS 350D/Digital Rebel XT/Kiss N Digital.

2.5mm miniplug accessories:

Remote Switch RS60-E3. A simple wired remote with a 60 cm cord. Two position button with optional lock feature for long exposure (bulb) photos. Note that there is a minor naming inconsistency between the RS60-E3 and its sibling, the RS-80N3.

N3 connectors.

High end EOS cameras now ship with N3 connectors in lieu of T3 connectors. Like their predecessors they’re proprietary Canon-only connectors, but they’re less of a pain to use and are lockable. They’re not as fun as 2.5mm plugs since you can’t just go down to your local Radio Shack and buy a connector for purposes of playing around, but they are sturdier connectors in general and can’t get pulled out by mistake.

Cameras which use N3 connectors:

EOS 3, 1V, 1D, 1Ds, D30, D60, 10D, 1D mark II, 1Ds mark II, 20D, 20Da, 5D.

N3 accessories:

Canon Remote Switch RS-80N3. A simple wired remote with an 80 cm cord. Two position button with optional lock feature for long exposure (bulb) photos. Note that there is a minor naming inconsistency between the RS-80N3 and its sibling, the RS60-E3.

Extension Cord ET-1000N3. An incredibly expensive 10 metre (33 foot) extension cord for N3 releases.

Remote Switch Adapter RA-N3. A cable adapter which converts old T3 accessories for use with N3 camera bodies.

Timer Remote Controller TC-80N3. A handheld wired remote with a computerized timer and a backlit LCD screen. This feature-packed remote gives you all kinds of self-timer options including normal timers from 1 second to nearly 100 hours, an interval timer and so on.

Wireless Controller Set LC-4 and LC-5. These are both staggeringly expensive wireless infrared shutter release system for N3-equipped cameras, consisting of a separate transmitter and receiver. 100 metre range. The LC-4 is basically the LC-3 with an N3 connector attached instead of a T3 one.

The LC-5, introduced in 2005 in conjunction with the EF-S 60mm macro lens, is a minor upgrade to the LC-4. It adds what Canon call a one-shot release mode (1SR) which triggers the camera when a subject walks into range of a prefocussed camera. It can also wake a camera which has gone into low-power sleep mode. It’s odd that Canon chose to release the LC-5 in conjunction with the EF-S macro lens, since only one camera body at the time - the 20D - could use both products. The LC-5 also isn’t something that confers huge advantages to macro photography - a wired remote is usually just as good for this.

Third party shutter releases:

For years Canon were the only maker of EOS-compatible shutter releases. But in 2003 or so a Chinese firm based in Hong Kong, Adidt Tenologies (sic), produced a line of EOS-compatible products. Their M1 series is basically an RS-80N3 clone and consists of a simple handheld switch remote sold as three different products - with 2.5mm (M1-C1), T3 (M1-C2) or N3 (M1-C3) plugs. As one might expect, these products are a matter of getting what you pay for. They’re much cheaper than the equivalent Canon products but they’re also not as sturdily made. I have a more detailed review of these remotes. Note that more recently Adidt have produced a more interesting and innovative product, the R3 series of wireless remotes. These remotes use radio frequency (RF) signals rather than infrared, meaning you get much better range (up to 100 metres with one version) and you don’t need line of sight. They also have keychain pocket transmitters.

Oddly enough, it seems other companies have decided that there’s a huge market for Canon-compatible remotes, as since Adidt’s entry into the marketplace, two other firms have released remote products. One, Nova Photography, is another Chinese firm selling cloned switches that closely resemble the Canon RS-80N3 product. The other, Seculine, is a Korean firm selling a video viewfinder for SLR cameras. They sell an advanced version, the ZigView R, which has a number of interesting features, such as intervalometer timing, motion sensor shutter release (an animal moves into the field of view, for example), bulb release and so on.

Homemade fun:

It’s also a fun, albeit nerdy, hobby project to build your own remote transmitter. Since the Canon remote release circuit is extremely simple - two momentary normally-open single-pole switches - it’s simple to construct a homemade release that does the same thing.

I’ve built one myself using a radio-frequency remote kit. This consisted of a largeish box with relays which hooked up to the camera and a small pocket digital remote. I put a 2.5mm plug on it and then built a tiny 2.5mm socket into a Canon RS-80N3 remote. This way I can plug my radio remote receiver into any Canon camera that uses a 2.5mm socket or an N3 socket. You can also hook up cameras to infrared or laser tripwires to take wildlife photography (the animal effectively takes its own photo when it crosses the invisible beam of light!) and so on.

Should I get a wired or wireless shutter release?

Wired shutter releases use simple electrical wires with switches soldered to the end. Wireless shutter releases, on the other hand, work on the same principle as handheld remote controls for TV sets and other entertainment devices. They’re essentially small boxes which send pulses of digitally-encoded infrared energy, invisible to the human eye, through the air to the camera.

Most of Canon’s midrange cameras support both wired electric shutter releases and wireless infrared shutter releases. The wireless system is particularly convenient since the wireless receivers are built into the camera bodies and require no external receiver devices - you just need a tiny handheld transmitter to trigger the camera remotely.

Naturally there are pros and cons with buying the wired or wireless shutter releases for your camera, assuming your camera supports both. Which kind you need really depends on what you want to do, though since they’re fairly cheap as camera accessories go you might want to consider just buying one of each.

Wireless shutter releases:

Canon’s wireless shutter releases for midrange EOS cameras, the RC-1 and RC-5, are both miniature handheld devices powered by long-life lithium cells. They’re easily clipped to your camera’s neckstrap for portability and work only with certain EOS bodies designed to receive their signals, as listed below. (for more information on the two-piece LC-3, LC-4 and LC-5 wireless releases see the previous section)

Wireless releases are great for group photos when you need to be in the photo. You can set the camera to IR-receive mode, walk casually over to the rest of the group, press the wireless shutter remote in two-second timer mode, lower your hand and smile for the camera. No need to dash frantically over to the camera before its self-timer runs out or run long cables along the ground.

They’re also great for taking long time period exposures at night. When the camera is in bulb mode one press of the button opens the shutter and another press closes it. You can thus easily take bulb mode pictures without bumping the camera and blurring the picture.

The main drawbacks of the wireless system are as follows. First, the camera’s wireless receiver is built into the front of the body. This means that the wireless transmitters don’t work very well if you’re standing behind the camera. You can tape a piece of paper to the camera to reflect the infrared signal downwards, which sometimes helps, but it’s obviously not a great solution. Second, the IR receiver on earlier EOS cameras is mounted near the lens mount and is thus easily blocked by large lenses or lens hoods. Later cameras - the Kiss IIIL, the 30/33/7/Elan II/IIE and 300V/Kiss 5/Rebel Ti - have receivers mounted on the handgrips which makes them slightly less susceptible to this problem. Third, the cameras have time-out values linked to their IR receive modes. If you don’t take a photo within 5 minutes or so of setting the timer then the camera turns off its IR-ready mode, which limits its utility for certain applications. Fourth, Canon warn that the IR receivers are susceptible to interference from fluorescent lamps and may trigger inadvertently if brought too close to one, though I’ve never noticed this happening before. Finally, the transmitters are small and easily lost or broken, and have a range of just a few metres.

Despite these drawbacks, however, they’re really handy little devices and highly recommended for all EOS owners with cameras which can use them.

The main two Canon wireless transmitters compatible with midrange EOS cameras are the RC-1 and RC-5. The RC-1 is a small device about as big as a pack of chewing gum. It has a three position switch - off (lock), two-second delay and immediate release. You then press the release pushbutton to take a picture in either two-second delay mode (which can invoke mirror prefire on certain cameras) or immediately. The RC-5 is flatter and wider and, while intended for Canon’s point and shoot cameras, also works with infrared-compatible EOS cameras. It only has a two-second trigger mode, however, and cannot be set to fire immediately.

Note that there’s apparently also the RC-4, which seems to be a bit bigger than the RC-1 but with the limited feature set of the RC-5. I’ve never seen one and they appear to be available only in certain markets. So I don’t know for certain if it uses the same IR signals as the RC-1 and RC-5, as I’ve seen suggested.

One fun thing to experiment with is that some learning remotes for TVs and VCRs happen to support the same infrared control pulses as Canon’s camera remotes. It’s probably not immensely useful, as home entertainment remotes are fairly large, but it may turn out that you already have a camera remote sitting in your living room.

Wired shutter releases:

The RS-60E3 remote switch for low and midrange EOS cameras is more useful for taking photos when you’re behind the camera and don’t want or need to be in the picture. The cable is pretty short at 60cm, but can easily be extended with a cellular phone headset extension cable that has 2.5mm stereo plugs.

Unlike the wireless releases the wired releases have two-position pushbuttons, so you can meter and focus by pressing halfway and then shoot by pressing the switch all the way.

Note that there are significant differences between the way cameras work when triggered by wired versus wireless shutter releases. EOSdoc have a convenient (if daunting) table listing how the EOS 30/33/7/Elan 7/7E works with these two remotes.

Cameras with support for wireless shutter releases:

EOS cameras with built-in wireless infrared receivers only and no wired shutter release sockets:

EOS 100/Elan, 10/10s.

EOS cameras with both built-in wireless infrared receivers and 2.5mm wired shutter releases:

EOS 50/50E/55/Elan II/IIE, IX, EOS 30/33/7/Elan 7/7E, Kiss 3L (Japan only) EOS 300V/Rebel Ti/Kiss 5, EOS 300D/Digital Rebel/Kiss Digital, EOS 350D/Digital Rebel XT/Kiss N Digital, EOS 30V/33V/7S/Elan 7N/7EN.

Unfortunately, Canon’s semi-pro and pro cameras do not support wireless remotes directly. You can buy LC-3 and LC-4 receiver/transmitters for them, which give you ten times the range of the tiny remotes built into the midrange cameras, but those devices are extremely expensive and quite bulky.

What is an intervalometer?

A fancy name for an interval timer or time lapse timer. A normal self-timer will take a single photograph after a set period of time - usually 2 or 10 seconds. But what if you want to take a photo once every 5 minutes or once every hour? This is where interval timers come in handy. They are useful for taking photos of things which change over time, such as flowers opening up or the sun setting in the sky. On some cameras you can also combine the intervalometer with multiple exposures so you can take a single-frame photo showing the moon rising in the sky or the progress of a solar eclipse.

Only one EOS film camera shipped with a built-in intervalometer - the EOS 10/10s. However, you could add a Technical Back E to an EOS 600 series camera or the the Command Back E1 to an EOS 1, 1N or 1NRS. You can also buy an external intervalometer, the rather expensive Canon TC-80N3 (see above). This handheld device is compatible with all EOS cameras which use the N3 connector for remote shutter release.

There are add-on devices for hobbyists, scientists and other experimenters, such as the Digisnap line of products. Korean maker Seculine sell a video viewfinder for SLR cameras, the ZigView R, which has a number of interesting features including intervalometer timing. Additionally, most digital EOS cameras can be controlled remotely by personal computers and can easily be set up in this fashion, though of course must remain tethered to the Mac or PC using a USB cable the whole time. In fact, digital cameras are perfect for intervalometer work since you don’t have the limitation of the length of a roll of film - you can keep filling up your computer hard drive with nearly endless photographs.