The Sony A900 is the flagship model in the company's alpha SLR line, and the only one offering a full-frame sensor. The camera body is built of magnesium alloy to take substantial abuse while maintaining a relatively light weight, though there's no denying that at 30 oz. (850g) without lens, this is a hefty piece of gear. All buttons, dials and other components are sealed against dust and moisture. The shutter is rated at 100,000 releases, probably as much as anyone is likely to require, but lower than the rated lifetime of the full-frame Canon 5D Mark II and Nikon D700, both of which promise 150,000 shots.

Front


Back


Sides


Top


Bottom 


**Size Comparisons **


**In the Box **


SONY-A900-boxshot.jpg

• Sony A900 body (with body cap)

• NP-FM500H rechargeable battery

• BC-VM10 battery charger

• Wireless Remote Commander with clip

• USB cable

• Video cable

• Shoulder strap

• Software CD-ROM

• Instruction manual

**Color Accuracy ***(11.00) *


In our tests for color accuracy, the Sony A900 was an unimpressive performer compared with other high-end digital SLRs. When set to the color mode that has the least impact on accurate color reproduction, the A900 still had problems reproducing yellow and green values well, and the blues and purples also showed a noticeable color shift. Skintone reproduction, on the other hand, was quite precise.

Sony gets credit for offering multiple settings to tailor color reproduction to the subject at hand, in the form of Creative Styles (details below). There are 13 of them in all, ranging from the unobtrusive Neutral and Clear to the more aggressive Sunset and Vivid modes. For our color accuracy tests we first shot the X-Rite ColorChecker chart in each available color mode, then analyzed the resulting images using Imatest to determine the setting that produces the lowest color error. That's the mode we use for comparison purposes — for the A900, it turned out to be the Neutral Creative Style. Overall, this produced a color shift of 5.92 and a notable undersaturation at 90.28%. Of course, an undersaturated image offers a little extra flexibility when making adjustments with image editing software, but the color shift is problematic.

In the chart below we compare actual-size crops from photos of the eighteen color squares on the X-Rite ColorChecker chart taken with five cameras, using the most accurate color setting for each. The leftmost column shows the ideal color values from the original chart.

NOTE: Because of the way computer monitors reproduce colors, the images above do not exactly match the originals found on the chart or in the captured images. The chart should be used to judge the relative color shift, not the absolute captured colors.

The chart below compares overall color scores for each of our comparison cameras. The Sony A900 comes up notably short against the others, with the Canon 5D Mark II offering the best results.

Color Modes*(5.00)*


The Sony A900 offers a Creative Styles feature that tweaks color reproduction to favor the subject at hand. Contrast, saturation, sharpness and brightness are also affected by the choice of Creative Style. You'll find a full discussion of this feature in the Picture Effects section below, in addition to sample images shot at each setting. Here we've chosen five of the most useful options from the thirteen Creative Styles provided and prepared actual-size crops of each color patch taken from photos of the X-Rite ColorChecker chart shot in each mode, for comparison purposes.

NOTE: Because of the way computer monitors reproduce colors, the images above do not exactly match the originals found on the chart or in the captured images. The chart should be used to judge the relative color shift, not the absolute captured colors.

As expected in a professional-grade SLR, the Sony A900 supports both the sRGB and Adobe RGB color spaces, the latter useful mainly for commercial printing applications.

Long Exposure*(10.68)*


In our long exposure testing, which evaluates both color accuracy and image noise performance at shutter speeds from 1 second to 30 seconds, the Sony A900 scored very well, coming in second only to the Nikon D700 in our comparison group.The camera handled both tests with good results, maintaining a color error below 4 until the camera tipped into overexposure at the 30-second exposure, and average noise well below 1% across the board.

Dropping the lights in our lab down to a level found in a darkened room (20 lux, which is barely bright enough to read by), we set the camera to ISO 400 and shoot the X-Rite test chart at a range of exposure times, from 1 second to 30 seconds. These images are then analyzed using Imatest to measure image noise and color accuracy; for cameras offering long-exposure noise reduction, we run the test twice, with this function on and off.

Both color error and saturation changed very little between shutter speeds when shooting with the Sony A900 until we reached a 30-second exposure, when the shots were overexposed even with the aperture fully stopped down.

Long-exposure noise reduction seems like a great idea, but it is minimally effective in most of our tests, and sometimes actually makes matters worse. This was the case with the Sony A900; except at the slowest shutter speed, long exposure noise measured higher with noise reduction on, by as much as 20%. The explanation for this counterintutive result? Image noise is by its nature random. Long-exposure noise reduction systems attempt to recreate the noise in the original image by taking a second, shutter-closed exposure and then removing the noise found in the black exposure from the original. Problem is, removing random bits can quite logically do more harm than good.

As shown below, the Sony A900 and Nikon D700 produced substantially superior scores in this test, while the other full-frame camera in the field, the Canon 5D Mark II, scored slightly lower than even the APS-C-sensor Canon 50D and Nikon D90.

Noise*(6.68)*


The Sony A900 is a middle-of-the-pack performer when it comes to image noise. We found that with the noise reduction system turned off, the A900 started off well at ISO 200, with only the noise-busting Nikon D700 posting better figures, but as ISO settings increased, noise rose more quickly than the other cameras in our test group until, at ISO 3200, only the Canon 50D produced higher image noise. The noise reduction system is effective,  keeping average color noise below 1% through ISO 1600 at maximum level, but not as effective as the system found in the other cameras: the A900 displayed the highest average color noise levels among the tested cameras across the ISO range when all were set to their maximum noise reduction settings.

Image noise is to digital photography what film grain was in the old days — spots and dots most noticeable in areas of flat color, caused in this case by random electrical activity in the image capture process. To test how well each camera keeps this phenomenon under control, we shoot the X-Rite color chart under bright 3000 lux illumination, at each official ISO setting (low-light noise performance is measured separately, along with low-light color reproduction, in our Long Exposure testing). When there are multiple high ISO noise reduction levels, we shoot at each. For the Sony A900, this means four sets of data, one with noise reduction off and then three at different noise reduction settings.

As shown above, noise reduction processing didn't kick in until ISO 800, at which point it provided a substantial improvement over results with noise reduction turned off. The difference between the effects of the three settings, though, was quite small.

The noise trends among individual color channels and luma noise (the noise in gray areas of the photo) are consistent, though noise in the red channel is clearly more a problem for the A900, while yellow and green are better controlled.

All of our test cameras followed roughly the same progression when tested with noise reduction off, though the Sony image noise rose slightly faster than the Nikon D90 at the extremes of the ISO range.

We noted above that the noise reduction system had no signficant effect until we passed ISO 800, which accounts for the Sony's notably higher noise levels at that point compared to the other cameras in our group.

The overall noise score for the Sony A900 puts it behind all but the Canon 50D, though the differences among the scores aren't high enough to be very significant.

ISO*(6.00)*


Available ISO settings range from ISO 100 to 6400, all at full resolution, a more modest range than some competing cameras. Both the Canon 5D Mark II and Nikon D700, for example, offer extended-range ISO settings out to 25,600.

Sony doesn't follow the Canon / Nikon route of clearly labeling ISOs that produce less-than-optimal results with non-standard naming conventions (dubbing extended-range settings as L for Low or H for high and leaving ISO numbering off). Sony numbers the complete range but highlights ISOs below 200 and above 3200 with rules above and below in the menu screen. The manual says, 'The available luminosity limits for an image (dynamic range) are a little narrower in the range less than ISO 200. When ISO 3200 or higher is selected, the range is treated as an expanded range and the noise is more noticeable.' As shown in the actual-size image crops below, we don't see a major drop-off in dynamic range below 200, but there's no question image noise explodes when we pass the ISO 3200 mark, and has already jumped upward long before we get to that point.

When set to Auto ISO, you can set a limit to the acceptable ISO range. Five settings are available: 200-400, 200-800, 200-1600, 400-800 and 400-1600.

Resolution*(10.64)*


Merely piling on the megapixels doesn't necessarily translate into superior resolution performance, but there's no denying that the 24.6-megapixel Sony A900 spanked the competition in our resolution testing, achieving an overall score for this section nearly 25% higher than the Canon 5D Mark II, its nearest full-frame competitor.

Our resolution test is a multi-faceted challenge, factoring in both sharpness and chromatic aberration. For 2009 we enhanced our resolution testing to incorporate sharpness measurements not only at the center of the lens, but at points across the entire image, including the four corners and midpoints along the diagonal axes. When a kit lens is avaialble, that's what we use for our testing. Sony does not offer a recommended bundle, though, so we chose their SAL-24105, a 24-105mm lens with an f/3.5-4.5 aperture range which sells for $469.99. We felt this provided a practical zoom range for a primary lens, at a reasonable but not bargain price.

We photograph our test chart at three focal lengths, representing the minimum, maximum and midpoint of the zoom range. At each focal length, we shoot the minimum, maximum and mid-range aperture setting. Images are then analyzed using Imatest software for sharpness, chromatic aberration and distortion. Since distortion results are entirely lens-based, we don't factor these results into the overal resolution score, but we present the test results in the following section.

Distortion

With the lens at its widest 24mm setting, we measured 2.37% barrel distortion. By the time we zoomed to 70mm the lens switched to pincushion distortion at the 2.17 level, which rose modestly to 2.42% at the longest 105mm zoom. While these levels of distortion would be noticeable, particularly in demanding applications like architectural shooting, they are within an acceptable range for most photographic needs.

*Chromatic Aberration *(7.85)

Chromatic aberration refers to the misalignment of red, green and blue pixels, causing a noticeable color fringe along line edges. Shooting with the 24-105mm lens, the Sony A900 produced low levels of chromatic aberration in the middle of the zoom range from edge to edge. At the widest and longest telephoto settings, though, the corners became problematic, producing clearly visible fringing in our sample images. The difficulty wasn't symmetrical, with the most noticeable defects occurring on the horizontal plane on the right side. Of course, there's nothing unique about the trend shown here, but the Sony did underperform compared to the Nikon D90 and D700 outfitted with similarly ranged lenses.

  • Sharpness *(11.84)

To test image sharpness, we shoot our test chart at three zoom settings (widest, longest zoom and mid-range), at three focal lengths for each distance. We found that, outfitted with the 24-105mm lens used in our testing, the Sony A900 produced a very good image sharpness result overall, signficantly higher than either of its full-frame rivals (the Canon 5D Mark II and Nikon D700). Only the Nikon D90 fared better in our sharpness testing, and not by much of a margin.

At 24mm, the widest lens setting, the image is very sharp in the center, with a maximum lw/ph measurement of 1718 horizontally and 2011 vertically, when shot at f/9. At this zoom length, performance remains strong from corner to corner.

In the middle of the zoom range, maximum vertical resolution falls a bit to 1768 lw/ph, but the horizontal figure stays nearly the same at 1728 lw/ph. There is some softening midway between the center and the corners, but nothing that raises alarms.

Finally, at the full 105mm zoom, as long as the lens is stopped down a bit, the lens maintains very good sharpness, and only really falls off significantly away from the center, when shot with the aperture wide open. Here again, the discrepancy is no more than we'd expect given the settings in effect.

When compared to the other tested cameras, the Sony A900 is the leader in overall resolution performance among the full-frame cameras, with only the 12.3-megapixel Nikon D90 posting a higher score.

Picture Quality & Size Options*(14.45)*


The Sony A900 can shoot at three aspect ratios: the native 3:2 format, widescreen 16:9 and a reduced-resolution APS-C size capture for use when a lens designed for a smaller sensor size is attached.

 

 

JPEG images can be saved at three compression settings: Extra Fine, Fine and Standard. In addition, there are two RAW file formats available, a straight RAW file and a compressed RAW (cRAW) which will be about 60-70% the size of an uncompressed RAW file. Either RAW format can also be shot as RAW + JPEG, with a Large-size JPEG stored simultaneously.

Dynamic Range*(8.29)*

 


The Sony A900 performed very well in our dynamic range testing, bested only by the Canon 5D Mark II. All of our comparison cameras produced similar results at low ISO settings, but dynamic range inevitably declines as ISO increases, and the Sony and Canon maintained  levels above 5 stops out to ISO 1600 and  well over 4 stops at ISO 3200, which is a very strong result.

We measure dynamic range — the camera's ability to capture detail in both the brightest and darkest areas of an image — by repeatedly shooting a standard grayscale chart at multiple ISO settings, under tightly controlled conditions, then feeding the resulting files to Imatest, which combines the results to determine the overall dynamic range.

At ISO 200, the Sony A900 demonstrates an impressive 7.34-stop dynamic range, which falls off at a reasonable rate as ISO settings increase.

Only the Nikon D90 outperformed the Sony at ISO 200, as shown in the chart above. Taking results from all official ISO settings into acccount to produce an overall score, the Canon 5D Mark II is the strongest performer, but the Sony A900 comes in a respectable second.

 

Image Stabilization*(4.71)*


The A900 did a decent job of compensating for handshake; we found that with low levels of hand shake, images with the SteadyShot stabilization on were significantly sharper than with it off. However, this was reversed with larger amounts of hand shake; the system made the images slightly less sharp. Most SLRs try and deal with the way your hands shake by moving a small part of the lens, but the A900 takes a different approach; the image sensor is on a moving platform. When the gyroscopes in the camera detect that it is moving because your hands are shaking, this small platform moves to compensate. We test how well a camera deals with hand shake by putting it on a motion control platform, shaking the camera and taking a large number of photos with image stabilization on and off. We also test by moving the camera in both a horizontal (left to right) and vertical (up and down) direction, with two different levels of shake; one low and one high. We then analyze these photos to determine how sharp they are; the better the job the camera does of compensating for the camera movement, the sharper the photos will be. For more details on how this test works, see our How We Test article.

Our first test is for a low level of hand shake, such as when you are trying to hold the camera steady with two hands, or braced against a wall. In this situation, the camera only moves a small amount, but there is still more than enough shake to ruin an otherwise perfectly good picture. In this case, the SteadyShot feature of the A900 led to sharper images at all of the shutter speeds that we test at, ranging from 1/500 of a second right down to 1/8 of a second. The only exceptions here were when the camera was moving vertically (up and down); at 1/500 of a second  and 1/60 of a second, the SteadyShot system made things slightly worse. But overall, it did a very good job of compensating for the simulated hand shake in this test.

Our next test uses a higher level of shake; about the level you would get if you were trying to take a photo while walking, or while taking a candid shot one-handed. The A900 didn't do as well here: the larger amount of shake seemed to be more than the SteadyShot system could cope with when the camera was moving horizontally (left to right). On most of the shutter speeds the images taken with SteadyShot on were less sharp than with it turned off, as you can see in the examples below. There was some improvement in sharpness with vertical (up-down) movement, though, but we feel that the horizontal correction is more important,since handshake is more of a left-to-right movement than up-down. 

The bottom line here is that we would recommend that you leave SteadyShot turned on in any situation where hand shake is likely to be an issue, as it does a good job of making shots significantly sharper across the range of shutter speeds with small amounts of hand shake. However, like all image stabilization systems, it can't work miracles, and in situations with larger amounts of shake, it sometimes made things a little worse. So, turn it off if you are running around, but turn it on if you are standing still to take shots.

The A900 didn't have the problems that the Canon 5D Mark II had with stabilization results worse at some shutter speeds; it made improvements across the entire range. But it's no slam dunk; we found that the image stabilization of the Nikon D700  produced sharper images at the critical shutter speeds of 1/60 and 1/125 of a second. However, in overall performance, there was not that much difference between the A900 and D700.  You should remember, however, that the performance of the 5D Mark II and D700 is dependent on the lens, as the image stabilization on these cameras happens in the lens itself. This means that if you were to use either camera with a different lens, you would probably get very different results.

It is also worth remembering that the two different types of image stabilization have their pros and cons. The sensor approach used by the A900 means that the lens does not require any complex built-in mechanisms, and you'll get the benefit of image stabilization whatever type of lens you use. This could also mean that the lenses are cheaper as they are easier to make. However, the lens-based image stabilization that cameras like the Canon 5D Mark II and the D700 use means that you can upgrade the image stabilization whenever you buy a new lens, and the lens manufacturers are constantly improving the technology that they use.

Below are stills from some of our test photos taken with the Sony A900, showing an average image from the horizontal test. The target is a slanted line.

*NOTE: As of May 2010 we have revised our image stabilization testing procedure to consider only horizontal stabilization. The scores shown here are up to date.

*

Automatic White Balance*(10.30)*


The automatic white balance setting produced exceptionally accurate results when shooting under daylight illumination, and also scored well when shooting under fluorescent light. The problem arose under incandescent lights, which produced images that were distinctly over-warm. On balance, though, the A900 scored well here.

Shooting under daylight illumination using auto white balance, all of the cameras produced slightly cool results, though the offsets from the ideal for the Sony A900 and Nikon D700 are trivial.

There is a grim consistency to the inability of automatic white balance systems to cope adequately with incandescent lighting which, considering that's still the source of most household illumination, is profoundly not a good thing. The warming trend is less severe for the Sony A900 than for most of the competition, as shown below, though there's still an uncomfortable orange hue to the images shot on auto.

It's interesting that both Sony and Nikon warm up their images when shooting on auto under fluorescents, while Canon errs in the cooler direction, but not enough that you'd notice without a lab at your disposal.

Custom White Balance*(10.75)*


Taking a custom white balance reading effectively solved the problem we'd experienced when shooting under incandescent lights using the automatic white balance system. There were color accuracy improvements under fluorescent and daylight illumination as well, but these were already quite close to ideal values under auto white balance.

White Balance*(10.53)*


Taking both automatic and custom white balance accuracy into account, the Sony produces acceptable but not impressive overall results when compared to the other cameras in our roundup. The tests are conducted using a controlled lighting system that produces consistent color temperatures for each illumination setting. Images are analyzed using Imatest, which compares the captured colors to the ideal values from the X-Rite color chart.

White Balance Settings*(7.50)*


White balance controls are extensive, if sometimes quirky. In addition to the inevitable auto white balance control, there are six presets, as listed below. Each of these presets can the be fine-tuned to three values above or three values below the default setting. Unfiortunately, there's no clear indication of what effect these fine-tuning maneuvers have on the picture you're taking. A deep dive into the manual turns up the fact that each increment represents 10 Mired. A knowledge of photographic science tells you that the higher the Mired number, the higher the color temperature, but this is all getting a bit obscure. On other high-end cameras with white balance fine-tuning, such as the Canon 5D Mark II, you work with s a visual representation of the color space, moving along the blue-amber and magenta-green axes. This is a more straightforward, comprehensible approach.

Setting a custom white balance is simple enough, and there are three slots to store readings if you want to return to them later. You can also enter the white balance adjustment in degrees Kelvin, or enter the value of a green or magenta color compensation filter, between G9 and M9, with each increment approximately equal to CC filter number 5.

Sample Photos


Clicking on any of the large photos below will call up the full-size original, though considering the size of these 24.6-megapixel files, those with slow Internet connections should consider themselves forewarned.

 

 

 

 

 

 

Still Life Examples


 

 

Noise Examples


 

 

Playback Mode*(8.00)*


There are four different playback displays, though unlike most cameras they're not all triggered by the same button. Pressing DISP while in playback mode cycles through three screen layouts.The first shows basic picture data: memory card location (CF or Memory Stick), folder name and file number, image format, quality and size, shutter speed and aperture, date and time, ISO and file number/total images on the card. The second display gets rid of the card and folder/file name information and replaces it with a five-image thumbnail display along the top, which can be navigated using the joystick or control dials. The third DISP press makes all on-screen information disappear, leaving a blank screen.

On the right side of the LCD, though, is the C button, programmable for a range of functions while shooting, but dedicated to bringing up a histogram display during playback. Memory card location, folder and file number are shown above a thumbnail image, shooting mode, aperture and shutter speed, ISO, exposure compensation, metering mode, focal length, date, time and image number out of total images are shown below, and to the right are four stacked histograms, showing overall luminance, and individual graphs for the red, green and blue channels. Over- and under-exposed areas are highlighted in the thumbnail image.

To see a navigable full-screen thumbnail image display, press the AEL button (its playback-mode function is indicated by a barely visible blue icon). Pressing the DISP button toggles between 4-, 9- and 25-image grids. There is no calendar view to organize files by date taken, a useful feature found on many SLRs today.

Turning either control dial or pushing the joystick left or right lets you browse stored images. To enlarge the on-screen display, press the AF/MF - Enlarge button next to the rear control dial. The level of magnification ( up to 19x for large file-size images) is set by turning the rear control dial. Turning the front control dial browses images at the same magnfiication, a useful way to check sharpness among similar shots.

In-Camera Editing*(0.00)*


Nothing doing. You can gaze at your stored images as much as you like on the way home, but you can't adjust them in-camera at all.

Software*(5.25)*


The Sony A900 ships with four software applications, as described below. All but Picture Motion Browser are avaiable for booth PC and Mac. When it comes to organizing and viewing their precious photos, Mac owners will just have to muddle through with the far superior iPhoto.

Direct Print Options*(3.00)*


The Sony A900 supports direct computer-free output to a USB-connected PictBridge-compatible printer and the creation of a DPOF file to simplify ordering prints from a service bureau.

Sensor*(3.00)*


The full-frame CMOS image sensor measures 35.9 x 24.0 mm, with 25,720,000 gross pixels and 24,610,0000-pixel effective resolution. That puts it ahead of its primary full-frame competitors in The Great Megapixel Race, with the Canon 5D Mark II at 21.1 megapixels and a paltry 12.1 megapixels for the Nikon D700.

The A900 incorporates an automatic dust reduction system that shakes the sensor itself (already motorized to provide in-camera image stabilization) every time you turn off the camera.

The A900 sensor matches the 36 x 24mm dimensions of a frame of 35mm film, which avoids the apparent magnification that takes place when you mount a lens on a typical digital camera, with its smaller image sensor. With a smaller sensor, only the middle portion of the light coming through the lens is captured — basically the center becomes the entire photo. As seen below, the APS-C camera sensor used in most digital SLRs effectively multiplies the apparent lens size by a factor of 1.6. For the 24-105mm mm lens we used to test the A900, it would shoot like a 38-168mm lens. That means more telephoto zoom out of the same lens, but also crops out the wide-angle areas. With the A900 and other full-frame SLRs, you get the full side-to-side, top-to-bottom coverage the lens is capable of delivering.

 

Viewfinder*(10.25)*


The viewfinder offers nearly 100% coverage, a true standout feature, with excellent brightness and easy legibility for the data readout. The diopter control (-3.0 to +1.0 m-1) is located on the right of the viewfinder. There's a built-in viewfinder shutter, to prevent light leaking in when shooting on a tripod, a huge convenience compared to mounting a cover manually over the eyepiece. The control for this is on the left of the viewfinder. The A900 supports interchangeable focusing screens, including Type M screens that support very fast lenses and Type L screens that are equipped with a grid pattern.

SONY-A900-viewfinder.jpg

A sensor below the viewfinder turns the LCD on and off.

Beneath the viewfinder are sensors that automatically turn off the LCD monitor when you hold the camera up to your eye.

The viewfinder displays the following information:

 

LCD*(8.86)*


The standard for fine viewing in an upscale digital SLR today is a 3-inch LCD with 921,000-dot resolution, which is precisely what Sony delivers here. It's a handsome display when viewed straight on, though it does begin to gray out noticeably when held away at a moderate angle — not unusable, but not as wide-angle as the Canon 5D Mark II or Nikon D700.

LCD brightness can be adjusted in 11 steps. Sony was clever enough to display a grayscale chart on the brightness adjustment screen, which makes switching settings a lot more meaningful.

The rear screen menu display can be set to one of three modes by pressing the DISP button during shooting.  The Detailed Display provides an overview of most camera settings (see illustration below).

The enlarged display cuts down on the level of detail, but makes it more readable at a glance.

SONY-A900-Info-Display-Simp.jpg

 

Finally, pressing the DISP button a third time turns the display off.

One handy feature not found in competitive models is the way the A900 automatically senses when the camera is turned vertically (with either side on top) and swaps the screen display orientation to match.

SONY-A900-lcdvertical.jpg

*The rear display reorients itself automatically

when the camera is held vertically.*

LCD Panel

While the main LCD panel is a thing of beauty and a joy forever, the monochrome LCD on the top right seems like a begruding afterthough. It's small (only about an inch measured diagonally), with a minimal amount of information displayed. At least the button to the screen's right illuminates it effectively.

SONY-A900-lcdtop.jpg

The mono LCD display is small and disappointing.

 

 

Flash*(3.00)*


Sony apparently decided that, in line with its professional-grade features and pricing, they wouldn't include a pop-up flash in the A900 design. We may be snobs in certain regards, but we have to admit that the convenience of having a built-in flash still appeals to us. On the plus side, at least there's a built-in autofocus assist lamp: the Canon EOS 5D Mark II leaves that task to the external flash unit.

SONY-A900-flash.jpg

*No pop-up flash to be found,

just a hot shoe to be filled.*

 

Using external flash, six flash modes are supported:

 

Lens Mount*(8.50)*


The A900 is fully compatible with all alpha-series lenses and older Minolta A-type bayonet mount lenses (including the MAXXUM and

DYNAX series). DT-series lenses, built specifically for APS-C-format cameras, can be mounted, and the camera will automatically switch to an appropriate frame capture size when it detects a DT lens, but in many shooting situations there will be visible vignetting in the corners.

SONY-A900-lens-open.jpg
SONY-A900-lens-closed.jpg

Sony acquired the Minolta lens format when it bought the company's SLR operations.

The A900 is not sold in a kit configuration. For test purposes we shot primarily with the TK, which produced the following levels of magnification at the minimum, maximum and middle zoom settings.

Battery*(9.00)*


The A900 is powered by a NP-FM500H rechargeable lithium-ion battery. Sony estimates that the maximium number of shots per charge is 880, following CIPA testing standards, which is quite high but seems justified based on our shooting experience: Sony does know how to make high-quality batteries.

It will take 235 minutes for a fully depleted battery pack to be fully charged, according to Sony.

SONY-A900-battery-open.jpg
SONY-A900-battery-closed.jpg

Sony consistently produces long-lasting batteries, and the A900 is no exception.

Memory*(5.50)*


Sony loves to sell its proprietary Memory Stick format, but that doesn't mean the realities of the market are lost on them. The A900 will accept both Memory Stick Duo (up to 16-gigabyte capacity) and CompactFlash formats simultaneously.

SONY-A900-memory-open.jpg
SONY-A900-memory-closed.jpg

*The A900 supports both CompactFlash and Memory Stick formats,

one at a time or simultaneously.*

Jacks, Ports & Plugs*(4.50)*


The most noteworthy input/output feature of the A900 is the mini HDMI jack for connecting directly to a high-def TV. It's located on the left side of the camera back, in a compartment that also provides a proprietary jack for standard-definition video and USB data connection.

On the right side of the camera are two additional jacks, under separate covers. The top one is used to connect a wired remote control, the bottom for the optional AC-VQ900AM AC adapter ($150).

There is also a flash sync terminal on the front right of the camera, and an infrared remote sensor on the front camera grip for the included Remote Commander remote control.

SONY-A900-ports-open.jpg
SONY-A900-ports-closed.jpg
  *We're pleased to find a mini HDMI port for connecting to an HDTV, less happy with the proprietary USB/AV jack.* **Other Features***(3.00)* *** **Remote Commander. **Most SLRs are compatible with wireless remote controls, but this is the only one we can remember that actually ships with a fully functional remote as a standard feature rather than an added-cost option. The Remote Commander is small — roughly 3.6 x 1.6 x 0.4 inches (91.4 x 40.6 x 10.2mm) — and easily pocketable. It's useful while shooting, of course, with both an immediate shutter release and 2-second timer button (when the camera is set to Bulb, either button starts the exposure with a press, and stops it with a second press). In playback mode, the remote offers nearly all the functions found on the camera itself, including browsing from image to image, enlarging and reducing image display, starting a slideshow and even bringing up a histogram overlay. This capability is great if you've connected your camera to a TV and want to show off your photos in style from across the room.
SONY-A900-remote.jpg

*This little wireless remote

is very handy extra.*

 

Shooting Modes*(11.00)*


The shooting mode selection is fairly stripped-down on the Sony A900, without any fancy choices meant to coddle newbies (or make it easier for you to hand your camera to a friend for the occasional snapshot). The Auto mode is a  bit unusual, since it provides a great deal of flexibility.

 

Live View*(1.50)*


Sony knows how to build SLRs with Live View — the company's A300 and A350 models have this feature — but it's notably Missing in Action on the A900. Frankly, we don't see this as an enormous problem. While we've found some situations where shooting with Live View is practical (particularly studio still life shots), we don't find ourselves using it very much in regular shooting situations.

However, Sony did strike out in a new direction with a feature called Intelligent Preview, which we haven't encountered before. The idea is that you capture a temporary image (it's a low-res RAW file) by pressing the Preview button located next to the lens, facing toward the grip. This image is then displayed on screen and you can make interactive adjustments  to the camera settings, including shtuter speed, aperture, exposure compensation, dynamic range optimization and white balance, previewing the effects of the changes on the LCD. In some ways this is kind of intriguing, particularly when it comes to the dynamic range features: we took a shot of a brightly lit computer screen against a dark curtain and saw the background detail suddenly emerge from complete obscurity when we changed the DR enhancement setting to its maximum level. The flip side, though, is that this on-screen tweaking is time-consuming, and the image you're fiddling with is a low-res preview that cannot be saved. For most adjustments, we'd just as soon take a lot of shots at a variety of settings and sort 'em out later. Given the fact that a 24.6-megapixel image shot with the A900 will take up over 20 megabytes in JPEG and a whopping 35 megabytes in RAW format, though, we can see where Intelligent Preview may have its place.

 

Scene Modes*(0.00)*

 


There are no scene modes on the Sony A900, in the traditional point-and-shoot sense, incorporating the full array of exposure and image style controls. Instead, there is a sophisticated Creative Styles function, which allows the shooter to choose from thirteen different image style combinations (incorporating color reproduction skew, contrast, saturation, sharpness and dynamic range enhancement), each of which is customizable. These settings are covered in depth in the Picture Effects section below.

Picture Effects*(6.00)*


The Creative Style system is Sony's way of creating packaged groups of settings to fit particular shooting conditions. The A900 is brimming with choices, 13 in all. Sony describes them as follows. Each is shown with a crop from our still life, shot in the specified mode, to show the real-world effect of the Creative Style.

Each of these Creative Styles can be adjusted with the following five settings:

It's simple enough to change these parameters for the 13 included Creative Styles; the options are clearly labeled on the LCD display, and settings can be adjusted using either the joystick or the control wheels. What's oddly missing is the option to create your own mix of settings and save them as a custom Creative Style.

Focus*(14.25)*


The Sony A900 autofocus system uses 9 primary, user-selectable focus points plus 10 supplmentary ranging points. Autofocus sensitivity ranges from 0 to 18 EV (at ISO 100). An autofocus illuminator is positioned between the grip and the camera lens. According to Sony, its working range is approximately 3.3 to 23 feet (1 to 7m).

 

There are three choices when selecting a focus area:

 

Exposure*(6.00)*


The Sony A900 provides a single Auto exposure mode, which unlike some cameras does not lock out most settings adjustments, but instead returns them to default values and lets the user change them if desired. Program, aperture-priority, shutter-priority and full manual modes are also supported.

Exposure compensation is available in a ±3 EV range; the default increment is 1/3 EV, which can be changed to 1/2 EV through the Recording menu.

Exposure bracketing can be set for continuous shooting , where all three or five shots you request are taken with a single shutter press, or single shooting, where each shutter press takes another shot in the bracketed sequence.

The A900 offers an impressive dynamic range optimization capability to maintain detail in overly bright or deeply shadowed areas. The D-Range Optimizer system can be set to Standard, which attempts to compensate for over- and under-exposure across the image as a whole or Advanced Auto, which divides the image into sections to determine the range between subject and background to create a dynamic range adjustment. It is also possible to set the level manually, with five incremental settings available, or to turn the function off entirely. As seen below, we found the D-Range Optimizer did a nice job, particularly in enhancing shadowed areas, and while this inevitably comes with a significant increase in image noise, this won't be terribly noticeable if the final image will be used at a reasonable size.

 

Depth of Field Preview*(1.50)*


The Preview button located below the camera lens has two functions. Optical preview is the standard depth of field preview function, stopping down the aperture to show the actual focal range under the current settings. The alternative function for this button is Intelligent preview, as described in the Live View section above, which takes a photo and saves it in a temporary low-res RAW, then interactively reflects the effects of settings adjustments on screen.

Metering*(7.50)*


The Sony A900 uses a 39-segment honeycomb metering pattern plus one element covering the remaining area.

SONY-A900-honeycomb-375.jpg

*The 40-segment metering pattern

*Three metering modes are supported:

 

Exposure compensation is supported in a ±3 EV range, in 1/3 EV steps by default, with the option to select 1/2 EV increments in the recording menu.

Shutter Speed*(11.00)*


Shutter speeds range from 1/8000 second to 30 seconds, plus Bulb for extended exposures

Self-Timer*(2.00)*


The Sony A900 offers basic self-timer functionality:

The handheld Remote Commander wireless control also includes a 2-second self-timer release button.

Handling*(5.00)*


The Sony A900 is a bulky piece of gear, good for building up the forearms but not the kind of camera you're likely to casually carry along just in case a photo opportunity happens to pop up. The body alone weighs nearly two pounds (30 oz., or 850g) and measures 6.25 x 3.25 x 4.63 inches (156.3 x 81.9 x 116.9mm). We did most of our shooting with the relatively modest-sized 25-105mm zoom, which adds another 14 oz. (395g) to the party. We also tried out one of Sony's premium lenses, the 16-35mm Carl Zeiss wide-angle zoom, a lovely $1800 construction for shooting close-ups that happens to weigh as much as the camera body itself.

Of course, you expect full-frame cameras in this class to be hefty (the Sony body outweighs the Canon 5D Mark II by just over an ounce. but is actually lighter than the Nikon D700). The real question is, how well does the camera handle when you're shooting? And the answer here is, OK, but not great.

On the plus side, the LCD information displays rotate automatically from horizontal to vertical when you pivot the camera (vertical in either direction, it should be noted). And while this behavior can be defeated with a menu setting, we found it enormously helpful. The camera grip is nicely cushioned and textured, and there's a useful thumb rest at the top back to help balance the load, but the positioning isn't quite right. Either we kept the tip of our thumb on the rest, which keeps you from wrapping your fingers firmly around the front grip, or the thumb rest balanced against the thumb joint, which means the tip of your thumb cruises up against the metering and multi-selector controls. The balance isn't ideal either: holding your index finger over the shutter, located quite near the righthand edge of the camera, again pushes the meaty part of your hand away from the grip. And if you need to reach the top buttons for exposure compensation, drive mode, white balance and ISO setting, you're going to have to reposition the camera entirely to gain access,

Controls*(9.50)*


The two control dials, one mounted nearly vertically up in front of the shutter, one mounted horizontally just above the thumb rest, work nicely together. There is some confusion about which control handles what settting in some instances. Sometimes either one will do; when setting exposure compensation, for example, or browsing pictures in playback mode. When navigating through the menus, though, the rear control dial takes you from tab to tab, while the front dial moves the cursor vertically through the list of settings. Working with the camera on a regular basis, though, we got used to these idiosyncracies.

The controller that continued to bother us, though, was the multi-selector, which we're inclined to call a joystick. For changing settings and moving through the menu system, you can use the stick if you like or ignore it and use the wheel controls, which we much preferred. But you can't get away from it entirely, because pressing it in toward the camera body is the equivalent of an OK button, which we found uncomfortable to maneuver (especially when we were in a hurry) and imprecise.

We were less than thrilled with the positioning of the exposure compensation, drive mode, white balance and ISO buttons on top of the camera. There's really no convenient or comfortable way to press them: they require you to remove your finger from the shutter button, and move your hand and/or the camera substantially to push a button.

Menu*(7.00)*


There are basically two parts to the Sony A900 menu system: the traditional tabbed on-screen display you bring up by pressing the Menu button, and the Quick Navi screen, which makes all the settings displayed on the full-screen LCD information display changeable by pointing, clicking and scrolling.

The back information display toggles between two levels of detail by pressing the DISP button (it can also be turned off entirely in the same way). At either detail setting, pressing the Fn button makes this screen interactive. An orange highlight shows which setting is active — the highlight can be moved using the joystick. As for changing the highlighted setting, you can scroll through the available choices sequentially by rotating either control dial, or press the joystick in and opening up a menu screen of choices.

 

One smart feature in the on-screen menu system is the fact that all settings available on a page are immediately visible, without having to scroll down to discover them. Each menu section — Recording, Custom, Playback and Setup — consists of multiple pages. Turning the rear control dial or pushing the joystick horizontally moves directly from page to page. Turning the front control dial or pushing the joystick vertically moves up and down the menu pages, scrolling to the next page in order if you continue beyond the bottom of the current page.

Manual & Learning*(5.25)*


The camera instruction manual is quite small, which is handy if you want to carry it in your pocket, but does lead to squint-inducing type sizes. The material is well organized, written clearly and adequately illustrated. There are lots of cross-references to other relevant sections as you work your way through the manual, which makes up for an index that could be more complete.

Software documentation is handled entirely through the individual applications' help system. We would have preferred some kind of printed (or even disk-based) quick-start guide, but the writing and presentation are clear enough to making the learning process smooth, especially if you have enough screen space to keep both the program and the on-screen instructions visible simultaneously.

Speed & Timing 


The Sony A900 utilizes dual processors and an innovative shutter design to deliver an outstanding continuous shooting burst rate considering the tremendous file sizes involved.

 

Shot to Shot*(4.44)*


Sony claims a top burst-mode speed of 5 frames per second. We achieved an average of 4.44 in our lab testing, which is none too shabby, beating the only other camera producing 20+-megapixel images (the Canon 5D Mark II) by a healthy margin.

Drive/Burst Mode*(7.00)*


The Sony A900 offers two continuous-shooting settings; Hi shoots at a maximum of 5 frames per second, Lo shoots at a maximum 3 images per second. When shooting in Extra fine mode, up to 11 images can be captured in a burst, which climbs to 105 in Fine mode and 285 in Standard. Surprisingly, up to 12 RAW files can be captured continuously, slightly more than Extra fine JPEGs.

 

Movie Mode*(0.00)*


Sony Pictures may be in the movie business, but the Sony SLR division isn't. Of the SLRs shipping currently, only the Canon 5D Mark II and the Nikon D90 offer video recording capability.

 

 

Performance

When it comes to color accuracy, the Canon 5D Mark II achieved the highest scores in our comparison group, while the Sony A900 was the worst by a substantial margin. In our resolution testing, though, the Sony is the top scorer, with the Canon 5D Mark II significantly lower. While color performance under studio lights favored Canon, in our low-lighting long exposure test the A900 maintained color accuracy better; image noise for the two cameras was similar here. Sony did pull a full-frame coup when it comes to burst mode, delivering 4.4 frames per second in our speed testing to the 3.81 shots the Canon 5D Mark II managed, even though the Sony files are larger. Of course, one enormous difference between the two cameras comes in shooting video: the 5D Mark II offers handsome 1080p high-definition results, albeit with a few control hiccups, while the Sony has no movie mode at all.

Components

The Sony A900 delivers a superior viewfinder, with near 100% coverage that none of the other cameras in our tests can match. On the other hand, Sony didn't include any Live View capability at all, and while it's still not a feature we rely on much, the Canon 5D Mark II implementation is well done. Sony offers in-camera image stabilization, eliminating the need to purchase more expensive stabilized lenses, though Sony lenses still aren't selling all that cheaply. Neither of these cameras offers a built-in flash, but at least Sony provides a built-in autofocus illuminator; we found Canon's reliance on an external flash to provide this function annoying. The Canon 5D Mark II does provide a superior monochrome display on the camera top, with far more complete information than the small Sony screen.

Handling

While the size and weight of these two cameras are similar (the Sony is slightly heavier, shorter and wider), we prefer the feel of the Canon 5D Mark II. The grip feels more comfortable, the balance more manageable and the button positioning is certainly easier to manage, particularly when it comes to the poorly placed exposure compensation, drive mode, white balance and ISO buttons on the A900 top surface.

Controls

Canon pushes the limit when it comes to ISO range, venturing out to ISO 25,600 in the extended range, where Sony plays it safe with a top ISO of 6400 (and even that's designated as an extended setting). Both cameras provide three custom settings slots for easy access to your favorite combinations, a welcome feature. As for the Intelligent Preview capability, the company gets points for ingenuity, but we didn't find it as useful as the missing Live View feature would be in visualizing the effects of settings changes on your final image.

This section of the review was updated with revised results and scores on July 15, 2009. These changes did not affect the relative ratings of the reviewed cameras.

 

 

Performance

Especially considering the $1600 price gap between the two cameras, the Canon 50D produced some impressive comparative results, besting the Sony A900 in two color-related categories (color accuracy and white balance) and coming close in our image noise testing under studio lights (though lagging in the long exposure testing in subdued lighting). The Canon 50D offers a snappy 6 shots per second tested burst mode performance shooting at 15 megapixels, but the Sony is remarkably close with 4.44 fps at 24.6 megapixels.

Components

With it 24.6-megapixel full-frame sensor, the Sony A900 is clearly in a different class of camera when it comes to producing photo files that withstand tremendous enlargement and/or cropping with minimal image deterioration. If you're in a dark room, though, the Canon 50D does offer a convenient pop-up flash, versus the Sony expectation that you'll carry an external flash along with the already-bulky camera and lens. Both cameras provide 3-inch LCD screens with 921,000-dot resolution, so going with the Canon doesn't mean compromising on that score, though the excellent Sony A900 viewfinder is much more comfortable to use, and provides a more complete picture of the picture at hand.

Handling

The Canon 50D is a middleweight contender, not all that much lighter or smaller than the Sony A900 despite their different sensor configurations. However, we do prefer the grip on the 50D, particularly with the more agreeable button positioning that lets you reach key controls without repositioning your hand the way the Sony A900 demands. We also like the circular control wheel mounted on the back of the 50D, which rotates more smoothly and comfortably than the more conventional thumb-wheel controls on the A900.

Controls

The expanded ISO range of the Canon 50D gives it an apparent advantage, but given the noise levels when shooting at ISO 12800, that edge is more mathematical than practical. The two cameras match up spec for spec when it comes to shutter speed, exposure compensation and noise reduction capabilities, though the Canon 5D does offer the Live View feature the Sony lacks. We like the Canon menu system, which works efficiently and looks great on the high-res screen, but the Sony A900 Quick Navi system, which makes all the key settings accessible from a single LCD display, gives Sony the edge in this regard, particularly with the addition of automatic screen orientation rotation, a major boon when shooting in portrait mode.

This section of the review was updated with revised results and scores on July 15, 2009. These changes did not affect the relative ratings of the reviewed cameras.

 

 

Performance

The Nikon D90 is one of only two SLRs that offer video recording (the Canon 5D Mark II is the other), a feature that may or may not matter to you when shopping for a camera. When it come to still image performance, the Sony A900 equals or betters the D90 in resolution, white balance and long exposure testing, and comes up just a hair short in image noise (not the strongest suit of either camera). Color accuracy remains an A900 stumbling block, trailing all the other cameras we used for comparison purposes, and the D90 in particularly by a hefty margin. As for shot-to-shot time, the A900 and D90 turned in identical scores, pretty impressive for the Sony considering it's pumping out double the resolution.

Components

Beyond the major difference in sensor resolution (24.6 megapixels for the Sony A900 versus 12.3 megapixels for the Nikon D90), the Sony A900 boasts the best optical viewfinder we've seen, but no Live View mode at all, which the D90 does offer. Both systems provide handsome 3-inch 921,000-dot screens. The D90 has a pop-up flash, which the A900 lacks. And both cameras provide HDMI output for direct connection to an HDTV, though of course the A900 will use this strictly to show off your high-resolution images, while the D90 will also serve up 720p video.

Handling

The Nikon D90 has a big advantage when it comes to portability, and doesn't have the oddball button positioning problems we encountered on the Sony A900. The difference in build quality is immediately apparent, though, when you hop from camera to camera, with the rubberized grip material on the A900 contrasting with the plastic D90 feel.

Controls

In terms of shooting flexibility, the two cameras offer the same ISO range and nearly equal burst-mode shooting speeds, though the A900 shutter speed does go to 1/8000 second, which can be an advantage when shooting sports or similar scenes, particularly in bright daylight. The Nikon D90 menus look better than the unattractive black and orange Sony screens, but the scroll-free viewing of each menu page and the handy maneuverability of the dual-control-dial approach gives the A900 an advantage here, which is sealed by the easy-access Quick Navi full-screen menu system. For less experienced shooters, Nikon offers much more in the way of assistance than the more businesslike, pop-up-flash-free Sony, including preset scene modes (entirely absent from the A900) and extensive in-camera editing capabilties.

This section of the review was updated with revised results and scores on July 15, 2009. These changes did not affect the relative ratings of the reviewed cameras.

 

 

Performance

In this match-up of full-frame cameras, the Sony A900 takes the image resolution crown by a wide margin, and very nearly equals the exceptional image noise performance of the Nikon D700 in both full studio lighting and low-light conditions. To repeat what's become a familiar refrain, the Sony A900 color accuracy lags far behind the Nikon D700, and the same holds true for our color-based white balance testing. Both cameras deliver very good dynamic range performance.

Components

All full-frame cameras are not created equal: the sensor may have the same aspect ratio, but the Sony A900 delivers 24.6-megapixel effective resolution to the D700's 12.1 megapixels. Out of the three full-frame cameras we tested (the Canon 5D Mark II is the other), only the D700 offers a built-in flash, which we find valuable. Both the Sony and the Nikon include 3-inch 920,000-dot LCD displays, but the Nikon provides the Live View capability the Sony lacks (it's worth noting that Live View on the 5D Mark II offers a superior display when you're moving the camera quickly).

Handling

These are both substantial cameras, the Sony slightly wider, the Nikon slightly heavier, and neither is going to win any awards for easy portability. The Nikon is an easier camera to manage, better balanced and with a more comfortable grip, especially when holding the camera vertically (though the pivoting Sony information display is a big advantage when shooting in portrait mode). As for the arrangement of buttons and dials, we give the nod to the D700 — while both cameras provide dual control dials that make quick work of manual exposure settings, the button layout is more practical and easy to manage on the Nikon.

Controls

Nikon menus are lengthy and require some study before you figure out what's located where, which can slow you down when trying to change settings while shooting. The Nikon does avoid the Canon 'multi-selector' (what most of us would call a joystick), which feels finicky and requires a bit too much precision to push straight in, which is frequently required as an OK/Enter/Set button.

This section of the review was updated with revised results and scores on July 15, 2009. These changes did not affect the relative ratings of the reviewed cameras.

Meet the testers

Steve Morgenstern

Steve Morgenstern

Editor

Steve Morgenstern is a valued contributor to the Reviewed.com family of sites.

See all of Steve Morgenstern's reviews

Checking our work.

We use standardized and scientific testing methods to scrutinize every product and provide you with objectively accurate results. If you’ve found different results in your own research, email us and we’ll compare notes. If it looks substantial, we’ll gladly re-test a product to try and reproduce these results. After all, peer reviews are a critical part of any scientific process.

Shoot us an email