Canon T1i Exposure
Canon T1i Exposure
The Canon T1i provides a great deal of control functionality, leaving you the choice of going on fully automatic settings, or making fine-tuned adjustments as desired. Standard exposure modes include the usual Program, Aperture-Priority, Shutter-Priority, and full Manual modes, as well as some "Image Zone" (scene-based preset) modes. The "Image Zone" exposure modes include Portrait, Landscape, Close-up (macro), Sports, Night Portrait, and Flash Off modes. These modes preset a variety of camera parameters to make it easier for non-expert photographers to achieve good exposures in a variety of standard shooting situations. The Canon T1's Flash Off mode simply disables the flash and external Speedlite (if attached), and puts the camera under automatic exposure control. The full Auto mode takes over all camera functions, turning the Canon T1i into a very easy to use point-and-shoot camera, albeit a very capable one.
The Canon T1i also offers the relatively new "Creative Auto" mode, which attempts to make complex photographic functions like depth-of-field easier to use. The camera controls focus and general exposure, but leaves it up to the user to adjust the level to which background elements are in focus, and whether to freeze or blur motion. By expressing changes in terms of focus or freezing/blurring motion, this mode also helps to de-mystify aperture and shutter speed for the Canon T1i's entry-level users.
The Aperture Priority and Shutter Priority modes work much the same as on any other camera, allowing you to adjust one exposure variable while the Canon T1i selects the other for the best exposure. Program mode keeps both variables under automatic control, while Manual mode gives you full control over everything. The Automatic Depth-of-Field mode (A-DEP) uses all nine autofocus zones to determine the depth of field in the active subject area. Once the Canon T1i has determined the range of focusing distances present across the nine zones, it automatically computes the combination of aperture and shutter speed needed to render the nearest and furthest points in sharp focus.
Exposure metering options include Evaluative, Partial (8% of viewfinder at center), Spot (3.5% of viewfinder at center), and Center-weighted options. The Canon T1i's Exposure Compensation setting allows the user to increase or decrease the metered exposure by up to two stops positively or negatively, in one-third or one-half EV increments.
Here you can see the concentrations of three of the four meter settings. Center weighted is on the left (which also shows the 35-zone evaluative metering coverage area), 8% Partial in the center, and 3.5% Spot on the right.
ISO Sensitivity Options
The Canon T1i offers regular ISO equivalents of 100, 200, 400, 800, 1,600, and 3,200, with the option to use fractional settings in 1/3-EV increments (100, 125, 160...). The Canon T1i also offers two additional high-range ISO settings enabled when ISO?Expansion is turned on: ISO 6,400 and "H", which takes the camera to 12,800 equivalent. An Auto ISO mode adjusts the ISO as the camera thinks necessary, from 100 to 1,600.
An automatic exposure bracketing feature lets you set the Canon T1i's total exposure variation (across three shots) at anywhere from +/- one-third or one-half EV, all the way up to +/- 2 EV. The nice part is that the automatic variation is centered around whatever level of manual exposure compensation you have dialed in. Thus, you could manually set a positive exposure compensation of 0.7 EV, and then have the camera give you a variation of +/- 2/3 EV around that point.
AE/FE Lock (" * " button)
The Canon T1i has the simplified AE Lock button, which unbundles the AF Lock feature from the old button on the older EOS cameras like the 20D and 30D. Marked with an asterisk (*) symbol, the AE Lock button simply holds the exposure at one setting while you recompose the image. It's very useful when spot metering, but also when dealing with subjects where you want to draw your exposure from one place, while autofocusing on another. Pressing the button with the pop-up flash activated or with an external flash mounted activates the FE Lock (Flash Exposure) function, which fires the flash and locks the proper exposure for the following frame. (Note that this button's default function changes in Live View and Movie modes, where it triggers an AF cycle vs locking the exposure.)
White Balance Options
The Canon T1i offers a full range of White Balance settings, including six presets, an Auto setting, and a Custom setting. The six presets include Daylight, Shade, Cloudy, Tungsten, Fluorescent, and Flash. The Custom setting bases color balance on a previous exposure, meaning you can snap an image of a white card and then base the color temperature on that image. There is no support for directly entering a color temperature in Kelvin though, a feature more commonly found on professional models.
A White Balance bracketing option snaps only one image, but then writes three successive files from that single capture. Bracketing steps are from -/+ 3 stops in whole-stop increments. (Each stop corresponds to five mireds of a color conversion filter, for a total range of +/- 15 mireds. This corresponds to about a +/- 500K shift at a normal daylight color temperature of 5,500K.)
The Canon T1i's WB Bracketing is set on the same grid as the White Balance correction control. Fairly sophisticated, the white balance correction tool lets you shift the color balance toward more or less green vs magenta or blue vs amber, using a +/-9 step grid format. You move a highlighted square through the grid to adjust the color balance, and bracketing adjustments spread the single square into a cluster of three. It's a slightly more advanced interface than I'm used to seeing on consumer digital cameras, but a useful one that greatly extends the camera's color corrective abilities.
As with other recent Canon DSLRs, the Rebel T1i also offers a Picture Style option through the LCD menu, which lets you select from Standard, Portrait, Landscape, Neutral, Faithful, Monochrome, or three User Defined settings. In each of the preset modes, the contrast, saturation, sharpness, and tone are set for specific conditions. The three User Defined options let you manually adjust each variable, then save it as a custom parameter. Finally, you can set the camera's color space to sRGB or Adobe RGB.
Auto Lighting Optimizer (ALO)
First seen on the XSi, and carried forward to the EOS-50D and now the Rebel T1i, Canon's Auto Lighting Optimizer (ALO) function lets you expose for the highlights, preserving detail there, while the camera adjusts the image to open up the shadows. This happens on the fly, as the files are being written to the memory card, so there's no post-capture intervention by the user required to take advantage of this function. We weren't terribly impressed with ALO on the XSi, but the 50D and Rebel T1i offer four different settings for it, and the control on the 50D and T1i was quite effective. The ALO setting is made via Custom Function 7, where you can select options of Standard (the default), Low, Strong, or Disable.
Highlight Tone Priority (HTP)
Also included on the Canon T1i is Highlight Tone Priority (HTP for short), a feature that's been on Canon SLRs for some time now, and it's one that works quite well when dealing with subjects with important detail in strong highlights. (Think of the standard wedding dress shot, and you'll get the idea.) Digital cameras normally expose more like slide film: Once you hit a certain exposure level, detail just vanishes. This really becomes an issue when you're dealing with contrasty lighting and a subject with lots of highlights in it.
HTP's action is pretty subtle, but the results are very evident when dealing with strong highlights under harsh lighting. The way it works is to set the camera's base ISO up one notch, to 200, so it's only half-filling the sensor's pixels with charge during the exposure. The Canon T1i then alters its tone curve, basically compressing the top half (that would normally be blown out) into a smaller range, thereby preserving the highlight detail. You can do this yourself when working from RAW files, you just need to significantly underexpose most of the scene, and then fiddle with the tone curve to drastically reduce the contrast, but only in the extreme highlights. If that sounds difficult, it is; it can be a real time-sink, and very difficult to make the end result look natural. Canon's HTP does this for you automatically, though, and the results look just great: You have no sense that the camera has been making radical adjustments to its tone curve; you just see all the detail in the highlights that otherwise would be missing. HTP is controlled via Custom Function 6, giving you options to Disable (the default) or Enable it.
Continuous Shooting Mode and Self-Timer
The Canon T1i's Continuous Shooting mode is rated by Canon at 3.4 frames per second in high speed mode, for a total of 170 Large/Fine JPEG shots or 9 RAW before the buffer fills (at 1/500 sec. or faster). When shooting JPEGs of a very complex scene with a lot of sharp, fine detail may also compress less and result in lower buffer capacities, as was seen in our testing.
The Canon T1i's Drive setting also accesses three Self-Timer modes, which open the shutter 10 or 2 seconds after the Shutter button is pressed, giving you time to dash around in front of the camera. The third mode will take a programmable amount of shots (2 to 10 shots), after a 10 second delay. A Remote Control mode works with the dedicated and wireless remote units as well.
The images above were taken from our standardized test shots. For a collection of more pictorial photos, see our Canon EOS Rebel T1i (EOS 500D) Photo Gallery .
Not sure which camera to buy? Let your eyes be the ultimate judge! Visit our Comparometer(tm) to compare images from the Canon EOS Rebel T1i (EOS 500D) with those from other cameras you may be considering. The proof is in the pictures, so let your own eyes decide which you like best!