Hi from Light Crafts
Hello there,
I just became aware of this fascinating discussion about LZ, it is great to see what people think about our product and what their real needs are. LightZone is a very young product that tries to innovate digital photography, it is definitively not perfect and we're working very hard to improve it, mostly by listening what you guys have to say...
I thought I'd contribute to the discussion about our raw converter "hows" and give you guys my own "perspective" about it.
Our current RAW converter technology is developed in house by Light Crafts, it uses a very advanced demosaicing algorithm which is very fast and extracts lots of detail from the image. It works differently from most other demosaicing algorithms and it is based on techniques traditionally used to interpolate high resolution electromagnetic field measurements (pieces from another life of mine, I have a background in Electrical Engineering, Signal Processing, High Energy Physics and Computer Science).
Some people on some other forums find it very capable of subtle detail recovery:
http://forums.dpreview.com/forums/read.asp?forum=1009&message=20792738
As some of you remarked already prior to LightZone 1.5 we used the excellent dcraw to perform the demosaicing, which unfortunately turns out to be quite slow. Thereby I developed my own algorithm.
For the curious: we still use dcraw to decode the RAW image format and extract the RAW data from it, it does an excellent job and saves us a lot of development effort.
As some of you already remarked, our approach to RAW conversion is to do the minimum post-processing as possible by default: no sharpening, noise reduction or else in the conversion. We prefer to start with a "really raw" image and then use our regular tools to post process it.
Usually we only apply a default tone curve to the image (a ZoneMapper layer) to make it look like what most people would expect "out of the box", pleasing tones and colors and fairly open shadows.
Some cameras produce fairly noisy images or contain quite a bit if Moire because of weak or no anti-aliasing (e.g. the older Canon 1Ds, the new Leica M8), so by default we add a NR layer to deal with that.
If you don't like the default tone curve or want to modify the default conversion in any way (add default sharpening), you can alter the defaults and save them again as a default template for the camera in question.
In comparison to other RAW converters, I feel quite proud of Light Zone. Comparing it to ACR (turn off all the Auto stuff and set NR and Sharpening to zero) I find that our images have comparable or less conversion arifacts (a fact of life in image debayering) and are quite a bit sharper and reacher in detail. In most cases you don't really need additional sharpening, or very little of it.
Other RAW converters sometimes produce less artifacts (I am paricularly impressed with Capture One) but at the expense of significatively longer conversion times.
RAW conversion is still something like a black art, everybody has its own philosophy about it and jealously keeps its secrets. The bottom line to me is that modern digital cameras have oodles of pixels and trying to chase the last bit of artifacts in the image made more sense when you had to squeeze the most out of a 3M pixel camera, with 10M or more for entry-level cameras as we have now it becomes a bit pointless...
Images coming out of the latest Canon and Nikon cameras are impressively clean of artifacts and have tons of detail, IMHO this is mostly due to the fine tuning of Noise Reduction, IR and AA filters and microlenses technology. Oddly enough Medium Format backs seem to have lower image quality than average DSLRs these days.
Finally, all the template management and workflow stuff in LZ is still at its infancy, expect big improvements in the next few months.
Thank you guys very much again for your interest and insight, best regards,
- Fabio (the man behind LightZone)