Adam Welz's Weblog

experimenting with DxO Optics Pro

Posted in ALL BLOG POSTS, photography by adamwelz on July 13, 2009

Hi All

in a quest to get a handle on producing quality digital images I have decided to spend a little time each day getting to know a couple of software packages (after all, my pro photographer days were in the mid 90s to about 2000, when film was still king).

One package that intriges me, and that I bought ages ago but have only just now started tooling around with, is DxO Optics Pro, an image editing and processing programme. The rather bright people over at DxO have figured out various ways of compensating for a suite of lens defects, including colour fringing, curvilinear distortion and vignetting by doing detailed analyses of a range of lens/body combinations and then writing software that will use the shooting data from your camera to move pixels around to straighten wavy lines on the edge of the frame, get rid of horrid purple fringing and improve overall sharpness. DxO Optics Pro also has a range of other features including noise reduction etc. etc., and has been designed (to a large extent, but not yet completely) to talk to Adobe Lightroom, the image library/processing programme I’ve decided to use to archive and process my images.

First impressions are that DxO is rather slow on my mid-range machine, so I am definitely not going to be running all my images through it by default (in contrast, Lightroom is impressively fast). As an experiment I ran a ‘defective’ image through DxO using the manufacturer-recommended ‘default/auto’ settings to see what it did — this is a night scene shot on my Nikon D300 with Nikon 18-200mm VR lens at 18mm. The ISO was set to 3200. I call it ‘defective’ because it shows a lot of digital noise and plainly demonstrates the lens’ inability to keep lines straight.

Here is a JPEG generated by Lightroom (no modifications) from the NEF (i.e. Nikon RAW) file from the camera:

7146 Lightroom only no DxO 720

Here is the DxO version generated from the same NEF file:

7146 post-DxO 720

As you can see DxO has straightened lines very effectively – producing a far more accurately-rendered and natural-looking gate – although in moving pixels around has lost a few bits on the very edges of the frame. The Nikon 18-200mm lens, like all other extreme-range zooms, suffers from noticeable curvilinear distortion at most focal lengths and DxO has eliminated this nicely. DxO has also saturated the image’s colour and lost a lot of chroma- and luma-noise in the shadows, although in my view a little too much — some detail and tonal subtlety has been lost. I must figure out how to tone down the noise reduction or perhaps turn it off completely and just use Lightroom’s.

The learning curve continues!