对于刚刚入了A900的人看了DP的文章非常郁闷。 好比本人。。。　但是我觉得原因可能是因为数据流太大，所以处理上太马虎，造成噪音严重。如果索尼能有发掘PS2 潜能那种精神来发掘A900 的最高性能，让ＢＩＯＮＺ处理器工作的更有效率，算法更优秀，　应该还是个可以用1-2 年的机器。看Ｄ７００　的价格，　我觉得Ａ９００　一年之后的零售价格应该在１２０００左右，如果能大幅度用固件升级提高ＩＳＯ的能力的话，也许是１４０００左右。　感觉相机的掉价速度实在是太快了．．　尤其是我这种１个月也没有一次外拍的人．．．．　

如果只用RAW可以关闭. 和JPG一起存不行.

A900是优点和缺点很分明的机器. 不过我感觉这机器除了像素和防抖, 其他短腿不少, 很难吸引人入SM.

按说, 2400万全幅不过相当于APS的1000万不到, 噪点应该没有这么差啊.

结果不出大家所料. 机身强悍, 带防抖, 但没有live view和视频. 噪点过了400就很厉害.

先看和D700对比结论:

                        A900   D700
Build quality  做工           9.5    9.0
Ergonomics & handling 人机工程   9.5    9.5
Features         功能        9.5    9.5
Image quality    图像质量        8.5    9.5
Performance (speed)  速度    9.0    9.5
Value            性价比        8.5    9.0

-------------------------------------------

Conclusion - Pros 优点:
Class-leading resolutionv (as long as your lenses are good enough)
incredibly solid build quality, environmental sealing
Intuitive operation and uncluttered control and menu system
Excellent out of camera JPEG results with superb tonality, dynamic range, color
Excellent raw dynamic range gives lots of headroom
Almost 100% reliable metering and exposure
Very fast and responsive body - remarkable burst mode (5fps RAW+JPEG, 24.6 MP)
In-body image stabilization that works well (around 2 stop advantage)
Wide range of image parameters and custom 'Creative Styles'
Dynamic Range Optimizer Advanced works well
Superb screen and attractive menu system
Excellent 'Quick Navi' control system
User-selectable noise reduction (though see cons, below)
The best (biggest, brightest) optical viewfinder on the market, 100% frame coverage
Excellent handling and ergonomics
Excellent battery life
HDMI output
Remote control included
Fast USB transfer and card writing (with a fast card)
--------------------------------

Conclusion - Cons 缺点:
Noise reduction settings applied to raw as well as JPEG files - cannot be 'turned off for raw but left on for JPEGs' (as is normal practice)
Relatively high levels of noise at anything over ISO 400 (ISO 6400 is of very, very limited use)
Destructive noise reduction on high ISO JPEGs removes too much detail
JPEGs a little soft by default (some loss of detail due to NR visible even at ISO 200) - you really need to shoot raw (and use ACR or similar) to get the best out of the sensor
Default color settings can produce red clipping (very saturated)
Top panel LCD very limited compared to all competitors
Less customizable than most competitors (though a lot less confusing for it)
No live view
No in-camera vignetting control
Intelligent preview of limited use in the real world (cannot check focus, for example)
Focus speed not up to other cameras in this class (though it is very accurate)
AF zone only covers a small part of the frame (not unique to this camera, of course)
No intelligent use of multiple cards (you have to switch manually)
Supplied raw processing software doesn't get the most out of the files (and is slow)
MS Duo slot pointless

========================================================
Overall conclusion
The Alpha 900 represents in a nutshell the almost schizophrenic nature of Sony's digital camera division, which can market compact cameras with smile detection and a Playstation style user interface at the same time as this, perhaps the most pared-down, frill-free and unashamedly 'serious' DSLR we've seen in a long time.

You can't help feel that Sony's long-held worry that as a consumer electronics giant it will never be totally accepted as a serious camera manufacturer has been instrumental in shaping a flagship camera that studiously avoids the creeping 'gadgetization' of DLSRs and concentrates on old fashioned stuff like picture taking.

And hey, for the most part this is no bad thing; the Alpha 900 is uniquely approachable for a camera in this class, has the best viewfinder on the market and produces, as long as you don't venture into the higher reaches of the ISO range range too often, very appealing output indeed. It feels and acts like a camera - in stark contrast to many of Sony's compacts, which seem to be designed to act like a cross between a camera phone and a games console - without offering the utility of either. Looking through the huge viewfinder you get the full advantage of the full frame format; the engulfing view makes you feel totally involved in the picture taking process.

No doubt about it, there is much to like about the Alpha 900 - from the quality of images it produces to the extensive control over image parameters and, as I've already mentioned, the excellent, intuitive and uniquely user-friendly handling. The built-in image stabilization is a real boon and makes the Alpha 900 a no brainer purchase for anyone with a sizeable Minolta 35mm camera lens collection. The only 'frippery' I found myself missing was live view (we do a lot of work in the studio where magnified live view, when done well, can be a real time saver), though not everyone will care.

Of course we can't talk about the Alpha 900 without talking about its 24.6 megapixel sensor; currently the highest resolution you can get in a 35mm format body (borne out by the class-leading resolution figures in our tests). What real advantage that gives most users is harder to say, especially when you factor in the rather disappointing high ISO performance that is the inevitable consequence of such a high pixel density, and the demands it puts on any lens you put in front of it - not to forget the fact the immense files will choke all but the most powerful PC and fill your hard disk in no time. But let's not knock Sony's achievement; at low ISO settings the Alpha 900 offers more resolution than any other digital SLR on the market, period - and for serious studio or landscape shooters this, combined with the excellent dynamic range, makes it an appealing option at a (relatively) affordable price point.

The biggest challenge to the Alpha 900 is probably the as yet untested Canon EOS 5D Mark II, which promises a similar resolution and a bag full of features (live view, video mode and so on) at a price that's around 10% lower. There's no doubt that existing Sony SLR and legacy Minolta film SLR users now have a fitting flagship model to salivate over and save up for, but in the face of such strong competitors the Alpha 900 may have a tough job persuading anyone to switch systems for it.

In conclusion this is, more than anything else at this end of the market, a true photographer's camera, with at least one totally unique feature (the Super SteadyShot stabilization) and one that offers the best viewfinder and highest nominal resolution (and the lowest 'cost per megapixel, incidentally) in its class. It's capable of stunning results at up to ISO 400 (and is fine at ISO 800-1600 as long as you're not printing posters), and it is incredibly fast and responsive in use. If Sony had managed to keep the price nearer to the $2000 mark (even if this meant fewer megapixels) I think it would be flying off the shelves. As it stands it will, I fear, struggle to make a serious impression on anyone other than the Sony/Minolta faithful. One thing is clear, however: anyone who thinks a consumer electronics giant can't make a heavyweight photographic tool is seriously misguided.

As long as you take into account our reservations about the high ISO image quality (which we'd more easily forgive on a camera that wasn't the best part of $3000), the Alpha 900 is a camera that just, by the skin of its teeth, offers enough to gain our highest award.

Detail (D-SLR)  Rating (out of 10)
Build quality 9.5
Ergonomics & handling 9.5
Features 9.5
Image quality 8.5
Performance (speed) 9.0
Value 8.5

[捞一把 编辑于 2008-10-23 05:28]