BY: Theano Nikitas, DigitalCameraReview.com Contributor
Sony certainly took the photography world by surprise when it announced its full-frame, 24 megapixel Alpha A900 DSLR. Perhaps even more interesting is that Sony followed up with the Alpha DSLR-A850, a sub-$2,000 (body only) version that makes it the least expensive full-frame camera on the market.
The new model, which also features a full-frame, 24 megapixel CMOS sensor, is almost identical to the A900 in terms of feature set and image quality. The main differences, of which there are only a few, include slower continuous shooting speed, viewfinder coverage of 98% vs. the A900's 100% coverage, and making the remote control an optional accessory instead of including it in the camera bundles.
Like other Sony DSLRs, the A850 doesn't offer Live View or video recording so if those features are important to you (and you're willing to give up the A850's in-camera image stabilization), you'll have to look elsewhere-most likely to the full-frame Canon 5D Mark II. It's the closest in price and resolution to the A850 and offers Live View and HD video recording, two features that we imagine Sony will add to its DSLR line at some point.
But the A850 offers an intelligent preview feature, which allows you to view an image before it's captured so you can tweak settings, including exposure, white balance and dynamic range optimization, to see what the image will look like. It's actually very useful, especially in mixed lighting situations where white balance adjustments are critical.
BUILD AND DESIGN
Sony wasn't joking around when it built the A850. Its solidly constructed magnesium alloy body should be able to withstand a lot of wear and tear. The camera is also sealed against moisture and dust, a real bonus for a camera in this price range. While designed for a comfortable handhold, the camera has some heft to it. Stripped down (i.e. no battery, memory card, neckstrap, etc.), the A850 weighs 1 pound 14 ounces and measures 6 1/8x4 5/8x3 1/4 inches (WxHxD).
I tested the camera with Sony's 24-70mm f/2.8 Carl Zeiss Vario-Sonnar lens, which is a really nice piece of glass. It costs almost as much as the A850 body but I'm a firm believer that you should always buy the highest quality lens you can afford (or save up until you can buy a good lens). There are may other lenses available from Sony and third-party manufacturers, so it's likely you can find something to fit your budget.
You may also want to budget for a few accessories, too, including Sony's HVL-F58AM flash. The A850 doesn't have an on-board flash but it does have a hotshoe. Unfortunately, the hotshoe connection is proprietary so you either have to purchase an adapter, use the flash sync terminal on the front of the camera or attach a compatible Sony flash. The good news is that the Sony HVL-F58AM flash is amazing. It supports wireless control up to three groups of flashes and its "Quick Shift Bounce" design (which I love) can be angled 90 degrees left and right for optimal vertical shooting so there's no need to use a bracket to flip your flash around to the correct over-the-lens position.
Also check out Sony's vertical grip for the A850. It's one of the most well thought-out designs I've ever used with the controls replicating those on the camera body. It also holds two extra batteries, with enough juice to shoot more than 800 shots per battery. For HD output, you'll need to purchase an HDMI cable. A remote control was bundled with the A900 but with the low price of the A850, Sony has made it an optional accessory so you'll have to shell out about $30 if you want the remote.
Ergonomics and Controls
Despite its bulk and heft, the A850 is comfortable to hold and pretty easy to shoot with, even if your hands are on the smaller side like mine. With the weighty 24-70mm lens attached, I didn't feel a lot of strain on my neck or arms and was able to hold the camera steady with relative ease for short periods of time.
One of the benefits of large cameras is that they have enough real estate for good-sized dials and buttons and this one is no exception. External buttons and dials are generously sized and, for the most part, easy to access and operate.
A quick overview of the camera's external controls include a good-sized mode dial on the top left surface providing access to Auto, Program, Aperture priority, Shutter priority, Manual exposure and three custom modes. Topside on the right, over the grip, you'll find dedicated buttons for changing ISO, white balance and exposure compensation. Dual control dials - one front and one rear - are well-positioned.
A small top panel LED can be illuminated by pressing a small button, though the panel itself is small and shows only limited information such as remaining shots and a battery gauge. Other settings appear as those functions are activated. I generally used the large information display/Quick Navi screen on the rear LCD. (The Quick Navi screen can be used to change settings, as well as view information.)
The power switch is on the left, which is a little confusing if you're used to it being on the right hand side as it is on many cameras. I occasionally forgot to turn off the camera simply because it was in an unusual place (unusual for me, at least). Vertically aligned along the left edge of the LCD you'll find the Menu, Display, Delete, and Playback buttons.
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Controls to the right of the LCD include an AE lock button surrounded by a lever for changing the metering mode, the AF/MF button, multi selector, along with Custom and Function buttons as well as a switch to turn Sony's SteadyShot image stabilization on and off. The Custom button can be assigned one of a number of functions including AF lock, Intelligent Preview, ISO, White Balance, Exposure Compensation and many more.
Like the A900, the A850 is also equipped with eyepiece sensors, although the A850 doesn't offer "eye start" that kicks the autofocus into gear when you put your eye to the viewfinder. Instead, the A850's sensors automatically turn off the LCD when you put the viewfinder up to your eye and vice versa.
Menus and Modes
The Quick Navi screen mentioned earlier provides access to a wide range of options and, in theory, makes short work of changing the most often used parameters such as exposure compensation, AF mode, metering, creative style, white balance, ISO, etc. I say "in theory" because each time you want to adjust a setting, you have to hit the Function button to switch from the status display to Quick Navi. Otherwise, it's very convenient to use.
Navigating the Sony A850's menus is relatively easy, even though the camera offers a large number of options. For example, in the Recording Menu you can set the image size, aspect ratio and quality, including multiple RAW and JPEG options with ease.
As expected, the A850 offers the standard DSLR complement of exposure modes: Auto, Program Auto, Aperture Priority, Shutter Speed Priority and full Manual (the user chooses both shutter and aperture values). There's also a Program Shift option, which allows the user to change the shutter speed and aperture combination by pressing the shutter button halfway and using the front or rear control dial to get the exposure combination you want. Using Program Shift doesn't change the exposure; it merely adjusts the shutter speed or aperture value.
There are also three Custom modes available on the mode dial so you can save and store a trio of your most often used setting combinations.
Display/Viewfinder
Everyone who has used the A900-including me-has been impressed with the camera's viewfinder. Similarly, the A850's viewfinder is large, bright, clear and a pleasure to use. While both cameras offer high quality viewfinders, the A850 offers only 98% coverage versus the A900's 100% coverage. It's unlikely that this will be a dealbreaker for most and even at 98%, the A850's viewfinder is very impressive.
The A850's 3.0 inch LCD is also impressive with its 921,600 pixel resolution. Even under bright sunshine, it's easy to read the status display and view images. Brightness is user-adjustable by +/- 5 levels but the default worked well for me.
I especially like that the battery life is not only represented visually but as a percentage (i.e., 98%) of remaining power. The status display also automatically rotates from horizontal to vertical when you change the camera's orientation so you don't have to crane your neck to read the on-screen data.
PERFORMANCE
Given its 24 megapixel CMOS sensor and all the pixels this camera has to push, the Sony A850 delivers pretty good performance thanks, in part, to its dual Bionz processors. It's important to note, however, that compared to other less megapixel intensive DSLRs, the A850 is about average (or, in some cases, a little slower). If you have your heart set on a 24 megapixel, full-frame camera but want a more responsive camera, you may want to go for the Sony A900 instead.
Shooting Performance
The A850 is responsive in single shot mode with the lack of shutter lag one expects from a DSLR. Auto focus is a hair slower than we'd like, but it's not very noticeable unless you spend your life testing other cameras like we do.
Shutter Lag (press-to-capture, pre-focused)
| Camera | Time (seconds) |
| Pentax K-7 | 0.02 |
| Sony Alpha DSLR-A850 | 0.02 |
| Nikon D300S | 0.02 |
| Canon EOS 1D Mark IV | 0.02 |
AF Acquisition (press-to-capture, no pre-focus)
| Camera | Time (seconds) |
| Nikon D300S | 0.15 |
| Canon EOS 1D Mark IV | 0.18 |
| Sony Alpha DSLR-A850 | 0.24 |
| Pentax K-7 | 0.29 |
Continuous Shooting
| Camera | Frames | Framerate* |
| Canon EOS 1D Mark IV | 25 | 10.7 fps |
| Nikon D300S | 14 | 6.9 fps |
| Pentax K-7 | 19 | 5.3 fps |
| Sony Alpha DSLR-A850 | 5 | 3.6 fps |
*Note: Continuous shooting framerates are based on the camera's fastest full-resolution JPEG continuous shooting mode, using the fastest media type available (300x CF, SDHC, etc.). "Frames" notes the number of captures recorded per burst before the camera stops/slows to clear the buffer.
As noted earlier, the A850's continuous shooting speed is slower than the A900 (3fps vs. 5fps) so you may want to go with the A900 if you're shooting a lot of fast-moving action. In our lab tests, we managed to squeeze about 3.6 fps out of the camera but overall performance, including continuous shooting speed, is partly dependent on the type of media card used. Although the A850 has dual card slots, only one accommodates CompactFlash types I and II; the other holds a Memory Stick PRO Duo. For the best performance, you'll need a high speed CF card like the Lexar Professional UDMA 600x or the SanDisk Extreme IV.
Lens Performance
There are several options for outfitting the Sony A850 with a lens. Sony has been growing its own line of lenses with a nice range of zoom, prime and macro options. Granted, your dream lens-like the 300mm f/2.8 G-Series-may cost three times as much as the camera, but other lenses are less expensive. However, investing in a really good piece of glass is really important, even if you have to give up Starbucks or eating out for a while. While I have nothing against $300 lenses, you're just not going to get the best from any DSLR if you skimp on lenses.
Also keep in mind that if you use a Sony DT (digital lens designed for APS-C size sensors), it will crop the image of this full-frame camera to about 11 megapixels. You may also notice some vignetting as well. Most of my testing was done with Sony's gorgeous 24-70mm Carl Zeiss Vario-Sonnar f/2.8 lens. Yes, it cost almost as much as the camera body but is well worth it.
Sony has a lens guide on www.sonystyle.com that's useful when deciding on what lens(es) to buy.
Image Quality
With the right lens and the appropriate settings, the Sony A850 is capable of producing excellent images both on-screen and in print. Using the 24-70mm Carl Zeiss Vario-Sonnar f/2.8 lens, images were sharp and detail capture was quite good. With the huge files produced by the A850, it's also possible to crop images without losing anything in quality (depending on how tightly the image is cropped, of course).
Colors at the default setting were generally natural looking but well-saturated. With all the tweaking options available on the A850, it's easy to adjust saturation and other parameters to get images that not only suit the situation but that suit your taste and aesthetics.
Exposures were, for the most part, very accurate across a number of different lighting conditions. Using Sony's DRO (Dynamic Range Optimization) feature helped maintain details in shadows and highlights under high contrast conditions, although at lower levels, the changes were often difficult to discern. Overall, however, DRO is effective and does what it promises, albeit sometimes subtly. This feature can be turned off as well.
Auto white balance accuracy was a mixed bag. Images shot under incandescent light were very warm. Multiple WB options-with fine-tuning capabilities-are available, however, to more accurately capture images under different lighting conditions and it's best to use the manual WB controls for most shots.
Auto White Balance, 3200k incandescent light
The A850 offers native ISO from 200 to 3200, which can be expanded to ISO 100 and 6400. I was generally comfortable with the results up to about ISO 800 and would use ISO 1600 when necessary. Image quality (color rendition rather than image noise) degraded slightly at ISO 100.
 ISO 100 |  ISO 100, 100% crop |
 ISO 200 |  ISO 200, 100% crop |
 ISO 400 |  ISO 400, 100% crop |
 ISO 800 |  ISO 800, 100% crop |
 ISO 1600 |  ISO 1600, 100% crop |
 ISO 3200 |  ISO 3200, 100% crop |
 ISO 6400 |  ISO 6400, 100% crop |
Like the A900, however, the A850 can't quite live up to the low noise performance of its closest competitors such as the Canon 5D Mark II and the Nikon D700. For the most part, however, image noise wasn't bad, even up to ISO 1000. What surprised me most was the extreme image noise at ISO 6400.
Granted, I tend to keep in-camera Noise Reduction turned off in all DSLRs since I'd rather deal with image noise with software rather than let the camera compensate for higher ISOs. On one occasion, I set the ISO to 6400 for an indoor shoot and forgot to change it when I went outside to shoot a model. I ended up with images that looked good at small sizes but, when enlarged to 100% on the computer screen, revealed blotching on the model's skin that made the image unusable for anything other than the Web or small prints.
Since image noise is often more prominent on skin, noise was slightly less visible on other areas of the image (including the front of the model's dress). Best bet for shooting high ISOs on the A850? Turn off noise reduction, shoot RAW and deal with it in post-processing.
Additional Sample Images
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CONCLUSIONS
Although slightly less capable than its older sibling, the A850 offers just about everything I liked about the A900 including a slew of sophisticated features that make it easy to capture great images. Its 24 megapixel sensor provides plenty of resolution, but be prepared to push all those pixels through your software in post-processing, especially if you're shooting at high ISOs.
It's also not as fast as the A900, but unless you're shooting really fast-action sports, its 3 fps continuous shooting speed should be fine. There are plenty of other options out there if you have a need for speed. While the A850 may not be perfect, it is currently the most affordable option for photographers who want a high resolution, full-frame camera.
Pros:
The most affordable full-frame, 24 megapixel camera on the market
Excellent resolution, sharp images (when used with a high end lens)
Natural color reproduction
Sophisticated feature set providing extensive user controls
Effective Dynamic Range Optimizer
Cons:
High end lenses can cost as much as, or more than, the camera
3 fps continuous shooting is below average for current DSLRs
High ISO performance could-and should-be better/less noisy
Proprietary hotshoe so you need an adapter to use other flash units, Pocket Wizard, etc.
