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Canon EOS Elan 7E AF & Metering
Peter Kun Frary
Auto Focus The Elan 7E's auto focus design is a masterful balance of flexibility, speed and accuracy. Like the EOS 1V and EOS 3, the Elan 7E uses a CMOS chip for its AF sensor, as opposed to the BASIS or Multi-BASIS chip used in older EOS cameras such as the A2 or 1N. There are seven AF sensors arranged in a cross array similar to the Rebel 2000 (EOS Kiss III/300).
The center AF sensor is a cross sensor and is sensitive to horizontal, vertical and diagonal lines. The top and bottom sensors are horizontal sensors and are sensitive to vertical and diagonal lines. The remaining AF sensors are vertical sensors and are sensitive to horizontal and diagonal lines. Seven cross sensors would be ideal, but this design yields a good balance between horizontal and vertical sensitivity.
Mount St. Helens EOS Elan 7E, EF 28-135 IS USM, Hoya Polarizing Filter & Elite Chrome
Individual sensors may be selected by eye-controlled focus (ECF), manually selected with button and/or dials, or automatically via fuzzy logic. The advantage of this system is that you can focus off-center subjects without locking focus and recomposing. AF modes include One Shot (stationary subjects), AI Servo (predictive follow focusing of moving objects) and AI Focus (automatic selection of One Shot or AI Servo).
Eye Controlled Focus (ECF)
ECF rocked the photographic world when it appeared in the EOS 5/A2E in 1992. The Elan 7E's implementation of ECF is more refined than that of the EOS 5/A2E, but operation is the same: focus by looking at the subject while pressing the shutter button. One of the seven AF sensors in the viewfinder confirms focus by flashing red. Foreground? Background? Off-center subject? It's your choice. No more locking focus and recomposing.
For ECF to work, it must be calibrated for your eye. Another person's calibration won't work for you. Calibration is simple: twist the knob to CAL and look at 4 flashing rectangles while pressing the shutter. Calibrations are cumulative, i.e., the camera learns to track your eye better with each calibration, especially if you calibrate with different lighting and lenses. It took me about a dozen calibrations to achieve consistent results. However, once calibrated, ECF was wonderfully fast and reliable in good light. ECF is noticeably faster than the A2E and Elan IIE. It's also a little more accurate that the EOS 3.
There is a gotcha for me: ECF is very sensitive to my eye's position relative to the viewfinder (your mileage may vary). If I shift my eye off-center or too close ECF fails, especially during calibration. I decided to install a larger eyecup, the ED-E, to see if it helped. The Ed-E is a big honkin' eyecup that wraps around your eye and blocks out external light. It can be rotated for vertical shots or for left-eyed folk. I also like it for its enhanced viewfinder visibility. What a difference it made! With the ED-E, ECF proved itself 100% reliable for me during daylight shooting. I believe the shielding from stray light, reduced squinting, and easier centering of my eye contributed to the improvement.
EOS Elan 7E with ED-E Eyecup, BP-300 Battery Pack and E-1 Handstrap The ED-E Eyecup helps reduce glare and greatly increases ECF reliability for me.
When shooting in extremely bright light--e.g., a white sand beach on a sunny day--you must position your eye carefully or extraneous light can confuse ECF. I solved this problem by installing the Canon Eyecup Ed-E on my Elan 7E.
ECF does not work with many sunglasses, especially those with reflective coatings. Thus, when donning shades I rely on automatic focusing point selection. Amazingly, the fuzzy logic chip nails the subject most of the time. Most eye glass and contact wearers report success with the Elan 7E's ECF.
ECF functions in most exposure modes except for Full Auto (Green Square).
AF Sensitivity
In good light, the Elan 7E focuses slightly faster than both my A2 and Elan. In fact, it's about as fast as the EOS 3. With an EF 50 1.4 USM mounted, the Elan 7E, EOS 3 and A2 lock on distant low contrast objects like white clouds without a hitch. However, the old Elan often searches and fails to get a lock on the same white clouds. As light gets dimmer, the Elan 7E's performance begins to waver and the Elan and A2 pull ahead due to their near-infrared AF assist lights (yes, you may use the Elan 7E's popup flash for AF assist, but that's too inelegant). Once outside the Elan's AF assist light range (25-30 feet), or with AF assist lights disabled, the Elan 7E is better at low light AF than the Elan. The EOS 3 and the A2--even with a disabled AF assist light--are noticeably better at low light AF than the Elan 7E.
Canon specs the autofocus of the Elan 7E within EV 1-18 with an EF 50 1.4 USM lens. Use of a slower lens reduces the lower range (each EV number = one stop). Thus, a F2.8 lens should AF at EV 3 (F2.8 at 1/8) or higher. Canon claims that the original EOS Elan, Elan II, A2, 1N, 1V and 3 have one additional stop of AF sensitivity, e.g., EV 0-18. Despite Canon's specs, low light effectiveness varies considerably between models. The pro models--1N, 3, 1V--have decent low light AF down to the bottom of their EV range without an AF assist light. Without an AF assist light, the Elan 7E and other lower priced models have problems 2 or 3 EV levels above their bottom range.
In all fairness, if there is enough light to hand hold the camera, AF will work fine on the Elan 7E. For example, EV 6 requires an exposure of F1.4 at 1/30 at ISO 100. With the EF 50 1.4 USM lens, AF is reliable down to EV 3 (F1.4 at 1/4 at ISO 100) in the low contrast lamp lighting of my living room. EV 2 was useable if I focused on a contrasty area. AF barely worked at EV 1 (F1.4 at 1 second), but this is definitely not hand holdable. Surprisingly, slower wide angle primes such as the EF 28 2.8 and EF 24 2.8 have one or two stops better low light AF than the EF 50 1.4 USM, probably due to increased depth of field. Nevertheless, with the AF assist light of the 420EX flash, low light AF performance of the Elan 7E is as good as or better than the older Elans.
However, the Elan 7E/EF 50 1.4 USM combo can effectively AF all the way down to EV 1, even EV 0 (F1.4 at 2 seconds), in high contrast lighting, e.g., city lights. Thus, I have frequently shot night cityscapes and Christmas lights with dependable and fast AF, even with the relatively slow EF 28-105 3.5-4.5 USM.
If you favor available light photography in twilight murkiness, AF sensitivity and the slightly dim viewfinder of the Elan 7E may be issues for you. Otherwise, the low light AF of the Elan 7E is fine--as good or better than past Elans--especially if you take a few simple precautions (see below).
The updated version of the Elan 7 series, the Elan 7N and 7NE, has slightly more reliable low light AF. Viewfinder size and brightness is the same as the Elan 7E.
How To Improve Low Light AF
All autofocus SLR cameras share similar limitations when shooting in low light. In low light photography, it is crucial to use fast lenses and focus on points of contrast. In other words, you can't merely point 'n shoot when lighting gets dim. You must pick your targets carefully. Here are some tips for low-light photography with the Elan 7E (these tips are useful with any EOS camera):
As light gets dimmer, AF is more reliable if you switch from ECF to automatic selection of AF sensors. Consequently, the fuzzy logic chip may enlist two or more sensors in the same plane of focus and achieve a lock more readily than a single ECF selected sensor. Why is this necessary? The outer AF sensors--sensitive mainly to horizontal lines--have difficulty focusing in low light and/or low contrast situations.
When it is really dim (e.g., a living room lit by table lamps), it is best to use only the center cross sensor (at this point you'll need a tripod). That is, manually select the center sensor and turn off all other AF sensors. It is extremely important to lock focus on a contrasty detail, e.g., an eyebrow rather than a smooth forehead. Furthermore, low light AF is enhanced considerably by using a fast prime lens such as the EF 50 1.4 USM or EF 35 2.0, rather than a slow zoom. The increased depth of field of a wide angle lens, e.g., EF 28 2.8, also helps improve low light AF. A bright image in the viewfinder is an additional benefit of using a fast lens.
In candlelight murkiness or complete darkness, you must use the irritating "AF assist light" (pop up flash) or the AF assist light of a Speedlite to autofocus. With a near-infrared AF assist light you may continue to use ECF or automatic focusing point selection. It's a shame Canon omitted the built-in near-infrared AF assist light. It made low-light AF elegant and convenient on the A2 and older Elans. When discreetness is paramount, you may disable the flash with a custom function (CF7-3) and use the AF assist light of the 420EX only. If you have good eyesight, you can still focus the old fashion way, manually!
Manual AF Sensor Selection
The Elan 7E introduces a small but significant innovation: direct manual selection of AF sensors via Focusing Point Keys--4 switches on top of the QCD. It's faster than pressing a button and cycling through the sensors with the QCD as on the EOS 3, A2E or Elan IIE. By pressing the toggle-like buttons, you may quickly focus around the frame without removing your eye from the viewfinder. Now, being a classical guitarist with a long thumbnail, I found the Focusing Point Keys too small and close and, thus, had trouble selecting individual keys. Either my nail bottomed out before the key was engaged or I hit two keys at once. Those with smaller thumbs and thumbnails should have no problems.
The good news about manual AF selection is, if one method doesn't work, you have four ways of manually selecting sensors via Custom Functions 11 and 12 (i.e., Focusing Point Keys, QCD, Main Dial & Focusing Point Selector). I like the option to select the center sensor by pressing the Focusing Point Selector once.
Manual AF selection only functions in the Creative Zone and is not operational in the Basic Zone (point 'n shoot modes).
AI Servo
This is a great camera for amateur sport shooters. Lock on to a moving subject in AI Servo with ECF, keep the shutter pressed halfway, and the camera tracks the subject as it moves from side to side (sensor to sensor) and towards or away from you. It confirms side to side movement with red sensor flashes! Very cool. AI Servo is better at nailing sharp images than the older Elans and A2.
AF Problems: Too Many Choices?
With all these AF choices, how can you go wrong? Actually, you can by choosing an inappropriate operation mode for your subject or shooting style. My wife complained the Elan 7E produced out of focus portraits of her guitar students. I checked her prints and, yes, many were out of focus. She took all her images in Full Auto (Basic Zone) and let the fuzzy logic chip select the subject. Unfortunately, it often locked AF on the shinny guitar strings or a bright background object rather than the eyes.
The cure is to take control of the camera, rather than letting it control you. She didn't like ECF or manual AF selection. Thus, I set the center AF sensor as the default and instructed her to use P (Creative Zone) instead of Full Auto (Basic Zone). She used the lock-AF-recompose technique she had grown accustom to with her old Elan and began cranking out sharp student portraits again.
Exposure Controls Like the Elan and Elan II, exposure modes are divided into two groups, the Basic Zone and Creative Zone. The Basic Zone consists of programmed point 'n shoot modes: Full Auto, Portrait, Landscape, Close-up, Sports and Night Scene. The Creative Zone sports semiautomatic and manual modes: Program AE, Aperture Priority, Shutter Priority, Manual and Depth of Field. These modes are clearly labeled and available at the twist of the Command Dial, a big knob on the top left side of the camera. Incidentally, the Command Dial feels solid--no play--and the metal slide release is easier to use than the original Elan or A2.
Creative Zone modes may be customized with special drive, AF and flash settings; custom functions; -2 to +2 of exposure compensation via the QCD (big wheel on the back) and auto bracketing. These settings don't function in the Basic Zone as Canon was afraid beginners would ruin pictures by accidentally touching camera controls.
Full Auto Mode
Full Auto and Program AE (P) are intended for general snapshots and follow similar algorithms. However, Program AE is a Creative Zone mode and, therefore, allows user customization and manual overrides. In contrast, Full Auto is a point 'n shoot mode and thus allows no manual overrides or customization. Fuzzy logic is used to control exposure, AF and flash. If the camera detects motion away or towards you, it switches to AI Servo (follow focus). If light is dim, the flash pops up. These modes are useful when you're in a hurry or you hand the camera to someone to take your picture. Unfortunately, sometimes the camera chooses silly aperture/shutter combinations. For example, with an EF 50 1.4 USM mounted and my camera pointed out the window, Program AE indicates F3.5 at 1/500 sec. This is a sensible exposure with an EF 300 2.8L USM. However, F4.5 at 1/250 or F6.7 at 1/25 are better choices with a 50mm lens. Although you may shift the program, I find Aperture Priority (Av) a better mode for most of my photography.
Programmed Image Modes
Portrait, Landscape, Close-up, Sports and Night Scene are specialized variations on Full Auto and are targeted at tyros. For example, Landscape mode is supposed to be used with a wide angle lens for sweeping vistas. To enhance depth of field, the camera stops down a little more than Full Auto, but not enough for my taste. Aperture Priority or DEP mode afford much better control of depth of field. The Programmed Image modes perform as advertised but may be improved on by user control in the Creative Zone. I don't use Programmed Image modes and would be happy if they were omitted from the design. Canon could use the savings to add a proper AF assist light and an illuminated LCD! Unlike Full Auto, ECF is fully functional in the Programmed Image modes.
Clearly labeled controls for most exposure, drive and AF modes
Meter Patterns
Like the earlier Elans, the Elan 7E has three metering patterns: evaluative, center-weighted and partial. Both the original Elan and the Elan II use a 6-zone silicon photocell for metering. The Elan 7E sports a 35-zone silicon photocell. Therefore, there are more zones for the camera's CPU to evaluate and supposedly render better exposures. I'm a chrome shooter and found exposure accuracy in my 16-zone A2 and 35-zone Elan 7E extremely similar, even in most tricky situations. However, my 21-zone EOS 3 is slightly more accurate in difficult situations.
The Elan 7E has a larger partial metering pattern than the older Elans: the original Elan is 6.5% of the picture, the Elan II is 9.5% and the Elan 7E is 10%. The smaller 6.5% pattern is desirable as you can more precisely measure isolated areas of the picture (a true spotmeter of 2 to 3% would be even better).
All meters can be fooled and you must learn when to manually override them (e.g., bright sunsets, strong backlight, predominantly light or dark scenes). With this said, I found the Elan 7E's exposures to be extremely accurate in most situations. When tricky lighting arose such as a sunset with silhouettes, I used partial metering and AE lock to meter an area I desired to be medium toned and let the highlights and shadows fall into place. As a point of comparison, I metered the same scene with the Evaluative pattern. Amazingly, the exposures were often the same. Evaluative metering is that good. In contrast, the Matrix meter in my old Nikon 8008S averaged the silhouettes with the bright sky, resulting in a washed out sunset (many automated print machines also do this to sunsets and other images that contain large areas of dark shadows).
Exposure Meter Range
The original Elan had a metering range of EV -1 to 20 and the Elan II, EV 1 to 20. The Elan 7E continues with a rating of EV 1-20. I want the 2 extra stops of meter sensitivity back!
Retractable Flash Like most midrange SLR cameras, the Elan 7E sports a retractable flash above the pentaprism. This flash uses 3-zone TTL flash metering linked to all 7 focusing points and syncs at 1/125 or slower. It's handy for fill flash and close snapshots, but not much else. Flash coverage is fixed at 28mm. In contrast, the original Elan had a 28-80mm auto zoom flash. The flash auto erects during backlighting or low light in Full Auto and some PIC modes. In Creative Zones (P, Av, Tv & M), you lift it up yourself. The Guide Number of 43 feet at 100 ISO translates into a 17 foot range with 100 ISO side film and the EF 28-105 F3.5-4.5 zoom.
EOS Elan 7E with retractable flash
The Elan 7E has one extremely irritating feature: use of the retractable flash as an AF assist light. A brilliant white strobe rapidly pulses in low light thereby blinding and confusing your subjects before you take the picture. Yuck! Well, at least red eye is reduced. The near-infrared AF assist light of the Elan and Elan IIE was discreet and elegant. Why change a good thing? You may disable the Elan's AF assist light with custom function #7. The EOS 10D's popup AF assist may be disabled with custom function #5.
Fortunately, there is a cure for the feeble popup flash and missing AF assist light: the 420EX Speedlite. Plus, the best flash features are hidden in the E-TTL circuits of the Elan 7E, and require an EX Speedlite to access them.
5/28/2001 Revised 6/28/2004
©Copyright 2001 by Peter Kun Frary All Rights Reserved .
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