Canon EOS-1Ds Mark IICanon upgrades their "ultimate" d-SLR with 16.7 megapixels of resolution and significant performance improvements.<<Sensor, Noise Reduction, and Optics :(Previous) | (Next): The "Red Problem," Description and Workaround>> Page 7:ExposureReview First Posted: 9/26/2005 |
Exposure
Wide Range of Exposure Options
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Noise Reduction System
The remaining exposure mode is Bulb, which simply allows you to take long exposures for unlimited periods of time, depending on the type of power source (With the new DIGIC II chip, Canon estimates a fully charged battery pack will allow for a 3-hour maximum exposure time, double that of the previous 1D and 1Ds; however the AC adapter allows for unlimited exposure times.) The 1Ds Mark II automatically employs a noise reduction system in exposures longer than 1/15-second (this function can be turned off through the Record menu when shot-to-shot cycle time is an issue). Most digital camera noise reduction systems use a "dark frame" approach, in which the camera shoots a reference frame the same duration as the exposure of the subject, only with the shutter closed, and then subtracts the resulting noise pattern from the captured sensor data to produce a final, reduced-noise image. Canon's CMOS sensor technology can apparently accomplish the fixed-pattern noise reduction processing right on the sensor chip itself, and so doesn't need to capture a separate dark frame to perform its anti-noise processing. As a result, the Canon 1Ds Mark II can capture long bulb exposures one right after another, without needing to wait in between to capture dark frames. This can greatly speed up long time-exposure photography, and would be especially helpful with the very long exposures required for astrophotography. To prevent any camera movement during long exposures (from holding down or releasing the Shutter button), it's best to work with the accessory remote control and attach the camera to a tripod. As was the case with the original EOS-1Ds, I was pleased to find that the noise reduction system worked even in Bulb exposure: The dark-frame noise suppression systems on most digital cameras I test are limited to timed exposures of relatively short duration.
In my testing, I found the Canon 1Ds Mark II's noise reduction system exceptionally effective. It won't work miracles with a very warm camera (image noise roughly doubles for every 8°C rise in temperature), but I rarely found any "hot pixels" in any of the bulb exposures I did, although I only tested it to roughly three minute exposure times. (If you do encounter any stuck pixels, I highly recommend Mike Chaney's Qimage Pro, a program with an amazing ability to remove spot noise without disturbing the underlying image.)
Metering Sensors
To determine exposure, the 1Ds Mark II borrows the 21-Zone Evaluative Metering system employed by other members of the EOS-1 series. Evaluative metering divides the image area into 21 zones of different sizes, with a honeycomb pattern in the central portion of the frame. The full Evaluative Metering mode determines the exposure by assessing each of the 21 zones and averaging the best exposure value for the entire frame. The 21-zone system also offers Center-Weighted and Partial metering modes. In Center-Weighted metering, the camera reads the exposure from the entire scene, but places emphasis on a large area in the center of the frame. Partial metering works along similar lines, but only places emphasis on approximately 8.5 percent of the center area. (Those readers familiar with the EOS-1D Mark II should note that the center metering area in the 1Ds occupies a smaller portion of the frame, only 8.5 percent, vs 13.5 percent in the 1D. - This is because the metering sensor is the same size in the two cameras, and so occupies a greater portion of the total frame area on the 1D, with its smaller sensor array.)
Spot Metering Options
In addition to the Evaluative Metering options, the 1Ds Mark II also offers a range of Spot metering choices. Normal Spot metering bases the exposure on a reading taken from the very center of the frame, and is usually chosen for use with high-contrast subjects. Alternatively, in some autofocus modes, you can choose to link the Spot metering area to one of nine or 11 active AF points. When you use Custom Function menu 13 to limit the selectable AF points to either nine or 11, the manually-selected AF point is linked to a 2.4 percent Spot Metering sensor (vs 3.8 percent in the 1D Mark II), centered on that point. Another option is to choose the Multi-Spot metering option, which bases the exposure on as many as eight separate readings from different parts of the image. In Multi-Spot metering mode, the central spot metering sensor is activated, and a meter reading is taken every time you press the "FEL" button on the top front of the camera. As you take successive readings, the exposure readouts in the viewfinder show the current aperture and shutter speed settings the camera has computed, while the vertical exposure level indicator shows the relative light levels corresponding to each of the points you measured. This is a pretty powerful exposure option, giving the photographer great control over the final exposure. The exposure level indicator gives you a pretty good idea of how much dynamic range the shot requires, and you can choose to give more weight to a given area of the image by taking multiple readings there. Very slick, a great feature!
Exposure Lock
As you'd expect, the 1Ds Mark II also offers an Exposure Lock option, which lets you lock exposure independently from the autofocus determination. You simply center the frame on the part of the subject you want to expose for, and press the AE Lock button, marked with an "*" on the camera. What's interesting though, is that this same AE Lock capability is extended to flash exposures when using Canon Speedlights. When shooting with an external flash, a Flash Exposure Lock option (the same FEL button used in the Multi-Spot metering mode) works with Spot metering to determine and lock the flash exposure. While not a multi-spot system, you can select a specific portion of the image on which to meter for flash exposure, just as you can with non-flash shots using the AE Lock button. You can also lock non-flash exposures, by pressing the AE Lock button marked with an "*" on the camera body.
Exposure Compensation
Exposure Compensation is adjustable from -3 to +3 exposure values (EV) in one-third-step increments. An Auto Exposure Bracketing option is available when you're not sure about the best exposure. Three images are captured in succession -- one at the metered exposure, one overexposed, and one underexposed. The amount of exposure variation can vary as much as +/-3 EV steps. In addition to aperture or shutter-speed based bracketing, the Mark II offers a unique ISO speed bracketing option. In this mode, the camera leaves the aperture and shutter settings at their predetermined values, and brackets the exposure by varying the ISO light sensitivity of the camera. Normal exposure bracketing is controlled by pressing and holding down the Mode and AF buttons on the left side of the camera, while rotating the (front) Main Dial. ISO bracketing is controlled by pressing and holding down the AF and metering/flash compensation buttons on the left side of the camera, while rotating the (rear) Quick Control Dial. The first image is taken at the set ISO value, followed by one at the next lowest value, and one at the next highest value. For example, exposure bracketing via the ISO setting in one-stop increments around the 200 value results in a series of images taken at 100, 200, and 400 ISO equivalents.
ISO Sensitivity
The EOS-1Ds Mark II's light sensitivity is adjustable from 100 to 1,600 ISO equivalents, which is expandable to 50 to 3,200 ISO equivalents through an custom menu option. ISO can be varied in 1/3 stop increments across the 100 - 1,600 range, but the extremes of 50 and 3200 are a full stop away from the nearest standard-range settings.
12 White Balance Modes
The EOS-1Ds Mark II offers 12 White Balance modes from which to choose, including Auto, Daylight, Shade, Overcast, Tungsten, Fluorescent, Flash, Custom, Color Temperature, and up to three separate Personal White Balance settings. Custom is the manual white balance option, which determines the white balance setting from a previously-captured image of a gray card. This method differs from the customary use of a white card held in front of the lens. (Other Canon pro SLRs also use this approach.) While slightly less convenient for on-the-fly white balance adjustment (you have to shoot the test image, then go back into the menu system to select it as the white balance reference), the advantages are actually manifold. First, you can easily store several different reference images on the camera's card, letting you quickly switch between different custom white balance settings. This can be very handy in environments where you need to quickly switch between radically different lighting environments. (Consider sports shooting, where you may want one custom setting for the stadium lights and another for the fluorescent lighting of the locker room.) Another advantage of Canon's custom white balance approach comes in scenarios where multiple photographers are covering the same event. The same set of white balance reference images can be loaded onto each shooter's CF cards, making for perfect color consistency between all the cameras and shooters. (A great help for post-event image workflow!). Here's a list of the available White Balance modes:
- Auto - (see below for information on Canon's unusual "Hybrid Auto" white balance)
- Daylight - Balanced for sunlight, approximately 5,200°K
- Shade - Balanced for open shade on sunny days, approximately 7,000°K
- Overcast - Balanced for cloudy skies or dusk, approximately 6,000°K
- Tungsten - Set up for professional tungsten studio lighting, approximately 3,200°K
- Fluorescent - "Typical" fluorescent (is there such a thing?), about 4,000°K
- Flash - Set to match EOS Speedlights, approximately 5,600°K
- Custom - The usual custom or "manual" white balance option, which bases the white balance adjustment on a shot of a white or gray reference card. The EOS-1Ds can accommodate a range of roughly 2,000°K - 10,000°K in this mode. (That's a very wide white balance range.)
- Manual Color Temperature Setting - This is an unusual mode we suspect will be very popular with photographers. You can specify the color temperature for neutral white balance in 100-degree increments from 2,800 to 10,000°K. Very nice, a feature we're surprised isn't widespread. (Why not extend it all the way down to the 2,000°K that the Custom option can handle, though?)
- Personal White Balance Settings (as many as three) - You can use Canon's software to create up to three custom white balance settings on the computer, and then upload them to the camera. These settings will then appear as options in the 1Ds Mark II's menu system. (This strikes us as potentially very useful for news organizations or other situations where you'd have multiple shooters working an event, and want to ensure color consistency between them.)
White Balance Bracketing
White Balance Bracketing is another useful feature common to Canon's high-end d-SLRs. You can set the camera to shoot three images at the same exposure level, varying the White Balance setting between shots by up to +/- 3 steps, each step being equivalent to five Mireds (Micro-reciprocal degrees). Mireds are a bit of an arcane measurement, but represent the units most directly applicable to the mathematics of color adjustment, their main benefit being that they're additive. A filter that shifts 3200°K light by 100°K will produce a much different shift (measured in degrees Kelvin) with 7000°K light, hence the use of mireds to describe the shift, rather than degrees Kelvin. (For example, five mireds at 3200°K is a shift of only 52°K, while five mireds at 7000°K is a shift of about 257°K.) This is all a little convoluted for the uninitiated, but pro photographers are accustomed to working with mireds in calculating filter factors, and professional color meters generally offer a mired scale for calculating filter corrections.)
White Balance in Degrees Kelvin
I also like Canon's provision of a Color Temperature white balance option, which allows the user to select the desired color temperature in 100-degree increments from 2,800°K to 10,000°K. I'd still like to see the lower end of this range extend a little further, since household and commercial incandescent lighting can reach as low as 2,500°K. Still, the Color Temperature white balance is very handy, particularly if the shooter has access to a color temperature meter.
"Personal" White Balance Settings for Rapid-fire Custom Changes
Finally, the Personal White Balance feature allows you to create as many as three different white balance settings on a computer and load them into the 1Ds Mark II for quick use. This strikes me as another great option for pros who have to shoot under highly variable lighting, or for groups of pros needing consistency between their setups. Not quite as flexible as the Custom option, because the Personal settings must be downloaded to the camera from a host computer, but arguably more powerful, not to mention having the advantage of allowing you to switch between three distinct custom settings very quickly.
"Color Matrix" options
The Canon 1Ds Mark II offers a nice range of color options, moving away from the tyranny of the sRGB color space. sRGB produces bright, saturated color on computer monitors, but has a woefully restricted color gamut. Bottom line, sRGB is fine for consumer-level devices, but is really unsuited for color-critical professional applications. Most d-SLRs these days include an option to use the so-called Adobe RGB color space in addition to the default sRGB. The Canon EOS-1Ds Mark II goes a step further, offering no fewer than five color-space options through the Record menu, plus the ability to store two customized settings. Canon calls these "Color Matrix" settings, and they offer an interesting range of possibilities. The table below lists their attributes.
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| Color Matrix 1 (Standard) |
Default color matrix. Normal saturation, sRGB color space. |
| Color Matrix 2 (Portrait) |
sRGB color space, but hue and chroma optimized for reproduction of skin tones. (A little warmer, more saturated in the reds and pinks.) |
| Color Matrix 3 (High Saturation) |
sRGB color space, extra saturation. Intended to reproduce the characteristics of high-chroma slide film. |
| Color Matrix 4 (Adobe RGB) |
Adobe RGB color space, normal hue and chroma within that space. Much wider color gamut than sRGB, which means images will look dull on sRGB monitors. Excellent for use in color-managed workflows, particularly ones going to print as final output. |
| Color Matrix 5 (Low Saturation) |
Mysterious low-saturation color space. Apparently sRGB-based, but color saturation is lower than normal. |
| Color Matrix Settings 1 and 2 |
Preset settings. |
| Color Matrix Setup |
Lets you set your own custom color matrix. |
For the pros likely to buy this camera, I call particular attention to Color Matrix settings 4 and 5. Setting 4 is matched to Adobe RGB, providing the greater color gamut that color space offers. The EOS-1Ds Mark II's handling of Adobe RGB JPEGs is another area that's been enhanced relative to the performance of the original 1D. Thanks to its support of the EXIF 2.21 standard, the 1D Mark II now embeds an ICC color profile into the EXIF header of JPEG files, so EXIF 2.21-aware image editing applications can recognize and apply the proper color space parameters automatically. (With the original EOS-1Ds, it was up to you to be alert and configure your image editor properly when opening images shot with the Adobe RGB color space.) Note though, that only the more recent versions of most imaging applications will be EXIF 2.21-aware: Adobe Photoshop version 7 doesn't recognize the 1D Mark II's Adobe RGB tags in its JPEG files, but Photoshop CS does.
Color Matrix setting 5 is a little mysterious, as there are some indications Canon intended it to be a special wide-gamut color space, but now treats it simply as a low-saturation sRGB.
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