Canon EOS-1DCanon leaps into the professional SLR arena, with the fastest digital SLR on the planet!<<Optics :(Previous) | (Next): Shutter Lag & Cycle Time Tests>> Page 6:Exposure & FlashReview First Posted: 12/08/2001 |
Exposure
Wide Range of Exposure Options
With a design mimicking the 35mm EOS-1v model, the EOS-1D offers full manual
exposure control, as well as a complement of partial manual and automatic exposure
modes. For example, you can choose between Program AE, Aperture Priority, Shutter
Priority, Depth of Field AE, Manual, and Bulb modes. The majority of these are
fairly self-explanatory, as Program AE, Aperture Priority, Shutter Priority,
and Manual modes provide varying degrees of manual and automatic exposure control.
While available apertures vary with the lens used, shutter speeds range from
1/16,000 to 30 seconds in all modes except Bulb, which keeps the shutter open
as long as the Shutter button is depressed. (Interestingly, Bulb mode has no
time limit, other than the available charge in the battery (claimed in the manual
to be about 1.5 hours!) Canon's optional RS-80N3 remote switch and TC-80N3 Timer
Remote Controller allow you to take long time exposures without having to hold
your finger on the Shutter button. One interesting note is that in Program AE
mode, turning the Main dial on top of the camera cycles through a range of equivalent
exposure settings, allowing you to pick the best exposure with an emphasis on
either aperture or shutter speed, while letting the camera determine the exposure.
(This is commonly referred to as a "program shift" or "vari-program"
option.)
Depth of Field AE Mode
Canon's unique Depth of Field AE (DEP) mode works well when shooting scenes
with subjects that are separated from each other. (An example might be a shot
with one person standing in front of another.) Quite often, you'll want to stop
down the lens enough to guarantee that both of your subjects are in focus, but
won't know just how small an aperture is needed. You'll also want to keep the
aperture as large as possible, to reduce shutter times. Without the tedious
use of a depth-of-field table, it can be difficult to accurately determine the
best aperture and focus point to use. The EOS-1D takes the guesswork out of
situations like this, with its DEP mode. In this mode, the camera calculates
the maximum aperture that can be used to keep both subjects sharply focused.
When DEP is selected, the 1D uses only a single autofocus sensor in the center
of the field of view. You use this sensor to "show" the camera which
two objects you want to have simultaneously focused, and the camera does the
rest. You center the viewfinder on the first object (near or far, it doesn't
matter) and half-press the shutter button. The viewfinder displays "dEP
1" to indicate that it's measured the distance to the first object. You
repeat the process with the second object, upon which the viewfinder shows "dEP
2". The camera computes the maximum aperture that will hold both subjects
in focus, and sets the lens focal distance accordingly. Half-pressing the Shutter
button will show the aperture and shutter speed the camera has selected. Fully
pressing the Shutter button takes the picture. If 6 seconds past before the
shutter is pressed, the camera forgets the DEP points, letting you set a new
pair.
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 (Canon
estimates a fully charged battery pack will allow for a 1.5-hour maximum exposure
time, however the AC adapter allows for unlimited exposure times.) The EOS-1D
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). To reduce image noise, the camera 1D captures a second, blank,
image with the shutter closed, which is then compared against, and subtracted
from, the original to remove the noise. (I was somewhat surprised to find that
the noise reduction system worked even in Bulb exposure. The top LCD readout
displays "busy" if you try to take another shot while it's capturing
the dark frame reference image. Very slick! (It's the first time I've seen a
noise reduction system that works with such extremely long exposure times.)
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.
In my testing, I found the EOS-1D's noise reduction system very effective.
It won't work miracles with a warm camera (image noise roughly doubles for every
8°C rise in temperature), but it does a very good job of eliminating image
noise under normal shooting conditions. Depending on exposure times and CCD
temperature, you can still end up with quite a few "stuck" pixels
in bulb exposures, but the level is far below what it is with the noise reduction
turned off. (And for dealing with those remaining 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 EOS-1D borrows the 21-Zone Evaluative Metering system
employed by the 35mm EOS-1v. 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 13.5 percent
of the center area.
Spot Metering Options
In addition to the Evaluative Metering options, the EOS-1D 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 9 or 11 active AF points. When you
use Custom Function menu 13 to limit the selectable AF points to either 9 or
11, the manually-selected AF point is linked to a 3.8 percent Spot Metering
sensor, 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 EOS-1D 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 EOS-1D 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. I'm not pro shooter myself, but this feature has
elicited some interest from folks like Rob
Galbraith, who says that ISO bracketing just might convert him to automatic
exposure bracketing.
ISO Sensitivity
The EOS-1D's light sensitivity is adjustable from 200 to 1,600 ISO equivalents,
which is expandable to 100 to 3,200 ISO equivalents through an on-screen menu
option. You can experiment with a range of ISOs, by using the ISO Auto Bracketing
function to capture three images at different ISO settings. 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, bracketing the ISO around the 200
value results in a series of images taken at 100, 200, and 400 ISO equivalents.
One of the first questions people will ask about the EOS-1D is whether its images
are as noise-free at any given ISO setting as those recorded with the remarkable
EOS-D30, which uses a CMOS sensor with active-pixel technology. (As opposed
to the more conventional CCD in the EOS-1D.) As I commented earlier, my response
to this question is somewhat mixed. On a purely technical level, when I compared
noise levels in images shot with the EOS-1D and EOS-D30 under the same controlled
conditions, I found that the absolute noise levels in the images from the 1D
were lower. This conflicted somewhat with the visceral reaction I had when viewing
images from the two cameras. Visually, my subjective opinion is that the images
from the D30 were slightly superior, due to their buttery smoothness. Certainly,
the image noise levels from the 1D are very low, but I think there remains some
impossible-to-define characteristic of images from the D30's CMOS sensor that
render them more pleasing.
10 White Balance Modes
The EOS-1D offers 10 White Balance modes from which to choose, including Auto,
Daylight, Shade, Overcast, Tungsten, Fluorescent, Flash, Custom, Color Temperature,
and Personal White Balance. 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. (The D30 also used 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-1D can accommodate a range of roughly 2,000°K - 10,000°K in this mode. (Wow! That's a very wide white balance range.)
- Manual Color Temperature Setting - This is an unusual mode I 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 I'm 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 1D'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.)
Hybrid Auto White Balance
Here's a feature I've been expecting to turn up in digicams for a while now
-- white balance determination that's independent of subject color! Normally,
digicams compute white balance by analyzing the image captured by the sensor.
This is fine if the subject has no predominant coloration of its own, but fails
miserably for subjects with dominant color casts. (For instance, a model wearing
a red dress against a maroon background would trick the camera into thinking
the scene lighting was very reddish. The result would be an inappropriate cyan
correction being applied to the image, to counterbalance the red.) In the EOS-1D,
Canon has integrated an incident illumination sensor on the front of the camera
that ties into the white balance system. This gives the camera additional information
about the lighting, which is unaffected by subject coloration. I'll be interested
to see how this innovation works out in practice, but I applaud the basic concept.
White Balance Bracketing
White Balance Bracketing is another useful feature that Canon included in the
EOS-1D. 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 5 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, 5 mireds at
3200°K is a shift of only 52°K, while 5 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 liked 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 actually like to see the lower
end of this range extend a little further, since household and commercial incandescent
lighting tends to be more in the range of 2,500°K to 2,800°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
EOS-1D for quick use. This strikes us 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
We're (finally) starting to see a move 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.
Nikon took a step away from sRGB in its D1x and D1h models, by providing support
for the so-called Adobe RGB color space in addition to the default sRGB. The
EOS-1D goes a step further, offering no fewer than five color-space options
through the Record menu. Canon calls these "Color Matrix" settings,
and they offer an interesting range of possibilities. The table below lists
their attributes.
|
|
|
| Color Matrix 1 | Default color matrix. Normal saturation, sRGB color space. |
| Color Matrix 2 | 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 | sRGB color space, extra saturation. Intended to reproduce the characteristics of high-chroma slide film. |
| Color Matrix 4 | 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 | Mysterious low-saturation color space. Apparently sRGB-based, but color saturation is lower than normal. |
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, although Canon's documentation is careful to point out that the files created in this mode do not contain any ICC tag information identifying the color space as such. This means that you'll have to explicitly set the color space in your color management software to achieve accurate results. 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.
Tonality and Custom Tonal Curves
This is a major feature of the EOS-1D, but was also the source of some problems
in the first prototype units I tested: The original firmware for the
1D had an extremely contrasty total curve as its default setting. Firmware 1.0.1
corrected this quite a bit, but the tonal curve is still much more contrasty
than I like to see in a professional camera. Fortunately, the final production
model appears to have entirely corrected the problem, even though the firmware
versions still reads 1.0.1. The camera's 12-bit A/D conversion and excellent
electronics produce a wide dynamic range, providing a lot of tonal information
for the camera to work with in generating the final output file.
Canon recognizes that different pros may prefer different tonal curves, and
has thoughtfully provided a means to implement custom curves via the host computer.
Canon's included "acquire" software (which really does much more than
just acquire images) lets you create a custom tonal curve and then download
it into the computer. This tonal curve then becomes available via the "Parameters"
option in the LCD record menu.
While I really like the ability to custom edit the EOS-1D's tonal curves, I
unfortunately can't say the same for the software interface Canon provides to
perform the task. It's one of the most unfriendly applications I've encountered
in recent memory -- not so much because it's particularly difficult to understand,
but because it provides essentially no feedback on the effects of the adjustments
you're making, or for that matter, on the correspondence between the tonal curve
controls and what part of the visible tonal range they affect.
The screenshots below show the tone-curve editing window and a preview image of my horribly contrasty "outdoor portrait" test shot. (Dave here: Before I get taken to task yet again for how horrid the lighting is on this image, please note that the awful lighting is deliberate, intended to be a stress-test of how well cameras handle extreme contrast and harsh highlights. Of course you'd never set up a serious shot like this, but I wanted a test subject that would stretch the limits of the cameras I tested. This lighting certainly does that.)
NOTE that in the following, the "default" exposure and tone curve examples were taken from one of the early prototype cameras I tested, NOT the final production model. The point here is to simply show how the tone-curve editing feature works, and what it's results are, so please regard the photos as illustrative examples only, and NOT representative of the production cameras' actual performance!
The
top shot in the table at right shows a default exposure and tonal curve from
a prototype camera, while the bottom one shows a considerably modified tonal
curve, and the preview image resulting from it. (Click on the images to see
them 1:1 at their original size.) I can't say I'm completely happy with the
result, but that's a reflection of my limited skills, lack of time, and how
time-consuming the tool is to use, much more so than any lack of power in the
tool itself. This is all really straightforward, but as usual, the devil is
in the details. First of all, the preview images aren't generated in real-time,
but rather they take a good 12-13 seconds (on a 500 MHz G4 PowerMac) to be generated
when you request them. By the time you wait for the preview to appear and make
a few adjustments to the curve, it can easily take 30 seconds for iteration
of the curve. Worse, you have no idea what part of the image's tonal curve you're
actually affecting when you're making adjustments. It turns out that the midtone
range of the image actually corresponds to a point pretty far to the left side
of the tonal curve in the adjustment window. You'd think it would have been
easy to add an eyedropper control to the tonal curve function, so you could
click on a portion of the image and see where that particular point fell along
the curve. This would let you quickly see what you needed to adjust and by about
how much. As it is, you end up "flying blind," reduced to guessing
and then waiting for the preview image to find out whether or not you guessed
right.
Once you have a tonal curve you like, you can apply it to the image as you convert it to a JPEG, save it to disk to apply to other images, or (this is the cool part) download it to the camera, where it can be applied as part of the custom parameter sets. (Note though, that all three sets of custom parameters share the same tonal curve. The camera has room for only two tonal curves, its default and one custom one.) It's entirely possible that more experience twiddling with the curves would leave you more comfortable about what to move and by how much, but it looks to us like this would take a long time to achieve. Bottom line, I'm happy to see the custom tone curve capability included in the EOS-1D, but suggest that you allow a lot of time for playing with it! (A long weekend wouldn't be too much.)
| What's up with RAW? | |
|
Flash
Like most pro cameras, the EOS-1D has both an external flash hot-shoe as well
as an external PC socket for connecting a strobe. The hot-shoe accommodates
all Canon EX series speedlights, as well as a variety of third-party flash units.
A Flash Exposure Lock button allows users to lock the flash exposure in advance
of the shot, and a Flash Exposure Compensation option adjusts the overall flash
power from -3 to +3 EV in one-third-step increments (only for Canon EX series
speedlights). Automatic flash exposure bracketing is also available. A High
Speed Sync option synchronizes the flash with all shutter speeds available on
the EOS-1D, from 1/16,000 to 30 seconds. (Note though, that a full-power flash
almost invariably lasts longer than 1/16,000 second, so you won't see the full
flash power when working with a shutter speed that fast.) When using a Canon
EX flash unit, you can also sync up wireless slave units for greater coverage,
with no connecting wires, special codes, or anything. Full TTL flash metering
is available even with multi-flash wireless setups. (Canon's series of dedicated
Speedlights have a remarkable range of capabilities, really deserving of a review
of their own, rather than the very brief treatment I'm giving them here. Unfortunately,
I really don't have the time or space to go into all their functions, and the
details of how they integrate with the EOS-1D.)
Continuous Shooting
Two Continuous Shooting modes are available on the EOS-1D: High-Speed and Low-Speed.
High Speed Continuous Shooting captures as many as eight frames per second,
provided you're using a fast enough shutter speed. (For maximum frame rates,
Canon says you need to use a shutter speed of 1/500 second or faster.) Low-Speed
Continuous mode captures approximately three frames per second. In both modes,
the maximum burst series is 21 frames (unless memory space is limited to a smaller
number). Maximum burst length drops to 14 frames at ISO settings higher than
800. (See the Shutter Lag/Cycle Time section of the review below for more information
on shooting speed.)
Self-Timer Modes
The EOS-1D offers two Self-Timer modes, 10-Second and 2-Second. Both modes are
accessed through the Drive button on top of the camera, the same button that
activates the Continuous Shooting modes. The actual delay time in each Self-Timer
mode can be adjusted from the host computer, across a range of zero to 3600
seconds(!).
Reader Comments! --> Visit our discussion forum for the Canon EOS-1D!
Follow Imaging Resource: