FrankF asked if I could write up something about processing X-Trans raw files, noting that his usual adjustments for NEF files didn’t work with RAF files.
Straight off, and despite much dismissive hand waving by those who would use Adobe Lightroom or Camera Raw to process their files regardless of any opinion as to the quality of the end result for X-Trans files, I can only say that I’ve tried ACR at every update until CC Rent-a Shop came into play and the results, while tinkered with substantially about the edge, were still nowhere near as good as processors using Dave Coffin’s dcraw algorithms for the X-Trans demosaic.
So the following will not be for Adobe users as I don’t use LR/ACR for X-Trans. Ever.
As Frank uses Photo Ninja (as do I), I’ll run through what I do to convert X-Trans raw files using that program. This is just how I use it, I'm not suggesting it is gospel. I really like the results I get this way, so I guess that's what really matters to me - your needs might vary.
For whatever reason the folk at PN did individualise their program by assigning names to sliders that are not common in their effect to more conventionally consistent names in other makers’ programs. This isn’t really a problem once familiarity is gained, but can be confusing at first.
Here’s the image I used as Photo Ninja presented it straight from the demosaic. I used this image because it has fine detail, the highlights are overexposed, and there are many fine and small colour gradations - plus the folder was open on the computer anyway . As a photograph it isn’t anything much, but as a taxing of the demosaic it perhaps is.
The following is how I have found it best to use the controls - this might differ from any “official” instructions, but hey, whatever works....
Note that when you're working in any panel, clicking on the ◄► icon under the sliders (highlighted in screen grab below)will show the unprocessed image, releasing will show the processed image concerning that panel. After exiting one of the control panels for the overall menu, clicking on them will show the unprocessed image, releasing will show the processed image including all panels adjusted so far. So at any time you can flick back and forward between processed states without having to hunt all over the screen for a preview box to tick or un-tick.
Here’s a screen grab at 100% of the image as opened, along with clipped highlight indicators:
So here’s the PN controls panel as it has opened an un-worked image with default settings:
Starting at the top, and the first hurdle which had me stumped for a long time when I first used this current version of PN (and which took an email to PN support to get an answer) is the “Color correction” menu.
Misleading, because in it is the slider that controls what everyone else calls "Highlight recovery" but has been called “Color recovery” in PN. Further confusion is caused by the fact that its default setting is strength 100. At this setting PN will fill any blown highlights with an aggregate colour from the surrounding un-blown area, which can sometimes look awful, even taking on a solarised appearance.
The Color correction panel:
I have changed that default number to 50 in my prefs, which I find a better overall beginning setting for my files, but that might vary according to your shooting style. Whatever, it is something to be aware of.
On the whole PN and Fuji together seem to do a good job on colour balance, but if there’s a lot of green in shot you’ll probably have to do a custom WB and knock excessive magenta compensation out of the default. I didn't mess with WB in this case, though, although it could be improved a bit I suppose. For comparison purposes I also thought a constant WB might be more useful. I would have warmed it up, although in this case the cool tone serves to locate the scene on the cusp of winter during a cold (6°C) day rather effectively.
Next in the main panel is the primary adjustment menu - “Exposure and detail”.
These are the settings it opened the sample image with:
As can be seen, there’s a bit going on at the right of the histogram that’ll need hauling into line (clipped highlights indicated with the red line).
The first thing to keep in mind is to try to work from the top down in this panel. The Illumination and Exposure offset sliders directly affect one another and should be worked in concert, keeping an eye on the highlight clipping indication in the preview image as well as watching the histogram. In this case in order to haul the highlights back it will be necessary to further reduce Exposure, then return the image to its original overall brightness with the Illumination slider. (If the image is underexposed to the left of the histogram, then the opposite movements of these two sliders will be required, and contrast increases in that case).
As can be seen, the image no longer spills to the right, and the histogram light tones are a bit more centralised and the clipped highlights are recovered. The visual effect will be to have slightly flattened the contrast of the image, and as there is no need to adjust shadows as they are are not falling off the left of the histogram the Shadows and the Black sliders can be skipped and the Contrast slider gently bumped up until the shadows just start to block, and then backed off a bit. In this case enough punch was added back by shifting Contrast to +7.
The final slider in this panel is the Detail slider and this must be approached with the utmost caution with X-Trans files. With Bayer files it is relatively gentle but with Fuji X it is vicious and some real artefacting can occur. I’ve found that maximum setting of +4 is all I can use before things get choppy.
This slider can be used to the negative side with great effect to reduce grain noise, however, and sometimes works better than third party NR programs, or Noise Ninja itself, for that matter.
Next comes the Color enhancement window. This has three presets in a drop-down menu - “Plain" (obvious as to effect), “Portrait” (which darkens/dulls green and blue but lightens/accentuates yellows and reds) and “Scenic” which saturates all colours.
My default opening settings for this image:
I have set my prefs to open this in Portrait mode as above, and will then use the fine-tuning sliders to alter the depth and saturation of individual colours as indicated in the colour boxes above the sliders. Select a box (green in this case) and adjust the Hue and Hue affinity sliders to bring back the brightness to the greens that the “Portrait” preset had killed a bit much.
The rest of the control panels are more targeted and to be honest I rarely use them as I have other programs that do the job better. Occasionally I'll use the vignette for effect or the Chromatic aberration if processing a file taken with an older Nikon AI-s wide-angle, but the Fuji lenses really don't have any aberrations to worry about - at least none of mine do. Even the little Samyang 8mm fisheye is amazingly free or fringing.
For sharpening I use Helicon Filter as a Photoshop plug-in, specifically the “sharpen fine details” slider in the sharpening panel, which usually gets best results between +15 & +25, and it has the least halo effect of any sharpener I have used.
So here’s the finished processed shot
And here’s a set of 100% sections of the before, the after, and one final one with +15 Helicon Filter sharpening as well.
Processed and Helicon Sharpen Fine Details +15:
The final version here might be a bit over-sharpened for screen, but is about what I find prints best on my Epson 7800 using Innova Smooth Cotton High White and Ilford Gallerie Gold Fibre Silk.
Once familiar with the program, running through these adjustments takes only a few seconds, and from that point of view it is much quicker than other dcraw-based processors I've tried (Windows - I don't use Mac). But getting quick at it does take practice, as with anything.
As always we'll be compromised by the ancient web colour space of sRGB and jpeg compression. Of course this image was processed in 16-bit Pro Photo colour space, and saved so tagged as an uncompressed TIFF, which means it probably looks a whole lot different to what you may be seeing on your monitor. One day the Web will catch up, maybe after it is done trying to be a phone app and gets back to being something worthwhile.