RAW file conversion - what matters?

When I first converted to digital photography from film, I researched every RAW converter/photo editor I could find. And even though I looked hard at alternatives, Adobe Photoshop was the best overall converter and editor for me.  I sold a pretty nice lens to pay for it. Photoshop does nearly everything well, even if the interface isn't the easiest to learn.

I confess, I was pretty upset when Adobe decided to go with a subscription model.  I knew right away that wasn't going to work for me.  I'm an amateur.  I don't get paid.  I do photography for fun, but I don't do it every day.  

So I started researching alternative RAW converters.  The following information took me at least a year to gather.

I tried several, both paid and free: 

• Aftershot Pro (formerly Bibble), 
• Capture One,  
• Canon's DPP4 (only for Canon users),
• DarkTable 1.2.x (Linux/Mac only - I use Windows so I ran it in Linux via VirtualBox),
• DxO Optics Pro 9, 
• LightZone 4,
• Photo Ninja 1.2.5,
• RawTherapee 4.x,
• Photivo, 
• SilkyPix

I thought about Lightroom but I'm not sure I trust Adobe to keep that one free from subscription.

Some converters are easier to learn (and some have difficult learning curves), some are faster, some have nicer defaults than others, etc.  Some try to do everything, some do nothing automatically.  After months of experimentation, I came to realize I only cared about a few features:

• White Balance/Color space
• Highlight/Shadow recovery/Exposure
• Noise Reduction
• Lens corrections (if needed)
• Usability/speed

One of the things I have realized about these programs is that good or bad looking defaults don't tell you how well the program does using "best" settings.  Finding those best settings can take quite a bit of time and patience.  I am not convinced that I have learned how to get the best from each of the converters I've tried.

Some of the converters let you select from several demosiacing algorithms.  In practice, I found little difference between them.

I ruled out Lightzone because it seems to be missing a bunch of basic features, yet has a ton of fancy filters I don't care about.  I have not found a way to fix blown highlights.

White Balance/Color Space

Every converter can adjust white balance and color.  I think all of them have a spot tool where you can specify any region as neutral, and the app adjusts the color for the rest of the image based on that.  Most of the converters produce a decent default white balance, and I confess, that is an area where I struggled with Adobe in certain cases.  Every time I struggled with the white balance and color, I seemed to end up using DPP.  However, once I started playing with Photo Ninja, I found it really easy to make the colors either accurate, or have a nice 'pop' that for me is more difficult in the other converters.  I have played with RawTherapee more than most other raw converters, yet still find it very difficult to get the right color from it, and gave up on it for now.

I nearly gave up on Photivo early on due to a steep learning curve, but I gave it more time and got to learn the interface.  I found Photivo slower than most of the others, yet quite capable... until I realized it has limited color space options, and no matter what settings I have used, the saved TIFF looks very different from the preview in Photivo itself.  I do not have that problem with any other converter, so I know it isn't a calibration problem.  I tried adding ICC profiles for the color space(s) I wanted, and didn't see any benefit.  That was a showstopper, and eventually I threw in the towel on Photivo.  I hope they fix that in the future.  If they do, I will certainly give it another shot.

Highlight/Shadow recovery/Exposure

Highlight and Shadow recovery is a difficult problem.  The best highlight recovery I have seen is in Adobe, DxO, recent versions of Photo Ninja, and DPP (requires some fiddling in DPP4). The DPP4 highlight recovery is trickier than some; move the middle slider in the gamma adjustment curve if the normal highlight slider isn't good enough.   RawTherapee and Photivo defaults didn't work that well, but changing the blending mode gave me decent results in each of those two. DarkTable was pretty bad in the sample I tried (1.2.x), and was unable to recover any highlights regardless of settings.  That knocked DarkTable out of the race.  Likewise, I wasn't able to figure out how to do highlight recovery in Lightzone.

Noise Reduction

Most of the converters I tried did a very good job with noise reduction.  It isn't a distinguishing factor for me anymore.

I experimented with their various sharpening methods, and came to the conclusion that most of the time, I don't like capture sharpening, so that became mostly a non-issue.  If it is an issue for you, then I suggest you take a close look at DxO, DPP4, and Photo Ninja, which are superior to the rest.

Lens corrections

For lens corrections, I rate DxO the best (truly outstanding!), followed by Adobe, DPP, and Photo Ninja.  RawTherapee in theory can use Adobe LCP files, but somehow never seemed to handle CAs (Chromatic Aberrations) well.

I really like DxO, but after my trial period, I realized I had to pay more for the Elite version just because of the camera model I happen to own.  That bugged me and I decided it wasn't worth that much money over DPP, which is free.  But it has a lot of features and fantastic lens corrections available.  DPP only has corrections for Canon lenses, of course.  Photo Ninja appears to have more manual controls rather than lens profiles, but seems to also do a great job for my lenses by default, when needed, so I guess there are things happening under the hood based on the lens/camera detected.

Usability/Speed

Usability is clearly a matter of taste, but it is important enough to me that I had to mention briefly what I like and don't like.

Speed is more important perhaps. 

I ruled out Capture One, Aftershot Pro, and SilkyPix pretty quickly due to interface issues (no particular issues here, I just didn't like them).  They may well have some excellent features but I never got over the interface with them.  C1 in particular has a lot of followers, so don't let my tastes dissuade you from trying it.   RawTherapee appears to be very easy to learn, yet I have not mastered it in months of trying.  DPP4 is much improved over DPP3, but still not perfect. 

Photivo was trickier to learn, but I spent quite a bit of time with it. I found that by default you have to click a button to get the changes you made to execute.  It is quite slow in operation, but I like the interface. Too bad it doesn't appear to be actively developed anymore, and had the color space issues.  

At first, I didn't like the Photo Ninja interface that much, but a friend encouraged me to try it again, and patiently answered my questions.  Also, once I bothered to look, I found the help/instructions very clear and concise. After a little use, I learned to love how Photo Ninja operates. My favorite feature is the ability (in most contexts) to click between zooming to 100% and full-image views. That alone puts the usability of PN well above all the others.  PN has fewer options than some raw converters, but it has everything I care about; if I need more (such as selective sharpening, or dodging/burning, etc), I send the tiff to an editor.  PN is fast too.  I'm excited to see what the next major release looks like.

Summary

So in the end, I settled on two:  DPP and Photo Ninja.  I prefer Photo Ninja for nearly everything because DPP4 tends to overdo the contrast and saturation by default (where DPP3 was one of the most accurate converters on default settings).  I keep DPP around only because I found one example where Photo Ninja changed the color too much.  Also, DPP is slower than Photo Ninja, and DPP4 does not support my older images from older cameras, so I have both DPP3 and 4 installed.

Having used Photo Ninja for some months now, I like it more and more.  I found a bug related to my camera, and Picturecode listened, fixed the bug within a couple of days, had me test it further, and finally released a new version.  Name a big company that can do that!  They are very responsive to feedback.  Sometimes, they said "great idea, we'll work on that for the next release".  Sometimes, they pointed me to the manual.  But they always responded quickly and politely, and they always backed up their decisions with sound reasoning. They earned my respect and loyalty. The more I use it, the more I like it.

I mentioned not caring much about sharpening at the conversion step... but that has changed with Photo Ninja.  I actually use Photo Ninja's sharpening, often keeping the default settings.  I'm not sure how their algorithm works, but it avoids artifacts and halos very well, and sharpens on par with the best.  The only time I turn it off is when I need selective sharpening via masks/layers.

I like Photo Ninja so much that I barely use anything else.  I will sometimes use Photoshop for selective sharpening or dodging/burning, but now mostly it gets used for resizing images.  Once Photo Ninja improves the resizing feature, I feel I will use Photoshop even less, perhaps for just a handful of images per year.

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Update:  After all of the above, I found digiKam is available for Windows, and tried the raw conversion.  First impression is that it doesn't handle highlights any better than DarkTable or Lightzone.  I'll have to experiment with settings.

Update:  I keep reading great things about Iridient Developer.  When that becomes available for Windows and Linux, I'll try it.

Update:  I found a Windows version of DarkTable 2 on Partha's site, and found that version runs pretty quickly.  I'm still not a fan of having to import images and store changes in a database, nor do I like the sliders, but the quality has improved quite a bit and I'd say it is worth another look.

Update:  A friend pointed me to yet another free raw converter, Photoflow.  As of this update, it is in an early stage (0.2.6), but shows some promise in both quality and usability.