Image Quality

The DCS620x produces images of excellent quality, but then that's what you'd expect of a camera costing the thick end of $10,000. With it's huge dynamic range it's possible to take images in all sorts of difficult situations (where consumer digital cameras would fail horribly) and still pull off an excellent result, colour balance is second to none (but again we should expect that of the people who virtually invented the concept of colour management.. Kodak) and images are on the whole crisp and detailed.

The anti-alias filter does its job well, although it does introduce a slight softening to the images the sharpen option on the acquire module is more than capable of pulling that back. What was most of interest was the effect of the new CFA (Colour Filter Array) on overall colour balance. Two things struck me, firstly that the camera loved (over saturated) yellows and greens and tended to turn strong reds slightly orange. This is a small price to pay for the huge gain in sensitivity.


Strong Yellow / Green
Weak Red (too much green in pure reds)

As I mentioned earlier here are examples of the two most noticeable effects of the new CMY Colour Filter Array, strong yellows and greens (really in-your-face saturation levels) and a weakening of pure reds, the addition of green in the two red objects in the right hand image (robot, red colour patch) turns the red slightly orange.

Footnote: Word has it from Kodak that the next version of the TWAIN module will have an option to mildly de-saturate images which may correct this colour shift.

Dynamic Range

Something you won't find in any consumer digital camera (yet) is the huge amount of dynamic range available from Kodak's CCD's. That, combined with a 12-bit Analogue to Digital converter and you've got the ability to retrieve an image which initially seems horribly over or under exposed. Using the Exposure compensation option in the TWAIN module you can drag highlights down and pull out detail which was all but invisible previously (make sure you've read the DSC Host Software section of this review for details.

In the examples below you can see that it's possible to pull detail out of the "blown out" highlights on the front of the steps, skin tones of peoples faces and the (deliberately) overexposed vase. Very impressive performance.

Before compensation (Comp +0.0 EV)
After compensation (Comp -0.7 EV)
Before compensation (Comp +0.0 EV)
After compensation (Comp -1.0 EV)

Acquire sharpening

The TWAIN module supports four levels of sharpening, from None (sharpening off) to High, the examples below are the same image acquired at different sharpening levels. The last one is a special, acquired with no TWAIN sharpening but with a Photoshop Unsharpen mask applied afterwards (my preferred sharpening method).

Sharpening: None
Sharpening: Low
Sharpening: Medium
Sharpening: High
Sharpening: None + Photoshop Unsharpen Mask 0.7 pixel, 95%  

Standard test charts

As with all the of the "new style" reviews on this site we've shot the standard colour and resolution test charts with the DCS620x, suffice to say it produced the best resolution and colour results of any 2 megapixel camera (well duh). Slightly pointless to compare it to other "consumer" digital cameras but here is a comparison none the less...

Kodak DCS 620x
Nikon Coolpix 950
Nikon Coolpix 990