哪一款 iMac? Which iMac?

當選定用 Apple iMac 而不是 Windows 建立數碼黑房後，下一個問題是：哪一款 iMac? 較平宜的牌本，顯示器只有21.5吋，像數只有 1920x1080，如用作數碼黑房，還是要大一點才方便。較高級型號，擁有27吋顯示器，更重要的是像數高達 2560x1440，有較大空間用作編輯相片。兩款27吋的iMac，分別是處理器和顯示卡，較平宜的賣 HK$12,188，是3.2GHz Intel Core i3 和 ATI Radeon HD5670 (512MB)，而較昂貴的賣 HK$14,788，是2.8GHz Intel Quad-Core i5 和 ATI Radeon HD5750 (1GB)，售價高了21%，但性能卻只高出15%左右，其中我最關心的 Aperture 指標，更只高出11%。再加上我擔心較快的顯示卡每令機件運作的溫度過高，所以還是決定省點錢，買3.2GHz Core i3，把錢用於把記憶體加至8G為上算。雖然有網站的測試結果與我的結論相反，但我對速度的要求不是很高，而且也絕不會出售二手電腦，所以仍然維持以上決定。Digllord 的CPU速度測試也和我的估計吻合。不要忘記，連 Lightroom 3 也不能盡用四核！

Once I've decided to use Apple iMac, instead of Windows, to build up my digital darkroom, my next question is: which iMac? The 21.5" one only gives you a monitor with 1920x1080. I need more screen real estate to operate my digital darkroom, and thus I choose the 27" one, which gives me a screen with 2560x1440. The differences between the two 27" iMac are the CPU and display card. The one sold at HK$12,188 gives you 3.2GHz Intel Core i3 and ATI Radeon HD5670 with 512MB. The one sold at HK$14,788 gives you 2.8GHz Intel Quad-Core i5 and ATI Radeon HD5750 with 1GB. It's 21% more expensive, but it seems to boost the performance by about 15% only. The most significant benchmark, Aperture, sees only a 11% increase. I'm also concerned about the operating temperature of the faster display card. Thus I'll buy the Core i3 one, and saving some money for the memory upgrade to 8G. Although some commentators have reached a different conclusion, I won't change my decision because I don't demand top speed and I'll never resell my iMac. Digllord's findings of real life speed of CPUs also confirm my view. And don't forget that even Lightroom 3 cannot use all 4 cores fully!

暫時我找到最詳盡有關 iMac 的評論有以下幾個：

At the moment, the best iMac reviews that I can find are the following:

• CNET – Review By: Rich Brown
• PC Mag – Review By: Joel Santo Domingo
• Computer Shopper – Review By: Jonathan Rougeot
• Engadget – Review By: Nilay Patel
• AppleInsider – Review By: Daniel Eran Dilger
• Macworld – Review By: Roman Loyola
• Digllord – Review By: Lloyd