DxO Lighting Engine - Local Contrast :
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Under the DxO Lighting Tab, one of the controls that has a lot of potential for adjusting images in ways that other programs don't, is the Local Contrast setting. The DxO literature describes Local Contrast as altering contrast in a spatially-determined way, and that its effect is similar to dodging and burning. Local Contrast is described as in effect applying a varying tone curve across the image - unlike global contrast. |
Once again, it might be easier to grasp the possibilities here while looking at how it affects an image.
The photo here is one I took of a mime in Covent Garden, London.
I used the D2x and the Nikon 85mm f1.4 optic at f1.4
For comparison, here are five versions of the same image:
- the first is with the entire DxO Lighting tab deselected. ie, no adjustments.
- then there are three variations of the local contrast, 0%, Auto (28%), and 100%.
- the final version is where I used a blunt adjustment to the curves to lift the shadow areas,
but trying to keep the highlights the same.
In these images, you'll notice that the white of the dress and the mime's white painted face is largely unaffected by local contrast when set to auto (which turned out to be 28% for this particular image.) Only the darker background area is affected and the colours punchier and brighter.
In racking the global contrast between 0% and 100%, you can see the white areas are brighter. However, it looks different than the S-shaped curve of a global contrast adjustment would've.
Global contrast would've crushed the white areas, and made the brighter areas look more flat.
In comparison, the image where I crudely adjusted the curves in imitation of lifting the shadow areas, don't look nearly as good as any of these other versions.
And here are 100% crops at half-size:
This is one of the features of DxO Optics with which I was really impressed.
However they do it, the results look great.
Even more so for the simplicity of the adjustment.
Even making extreme changes from 0% to 100% gave versions which are equally acceptable to me.