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jev
29-01-2009, 3:52am
Talk about bad ideas... I went to Barcelona and took a Fuji S9600 compact camera with me that, as I am used to do with my DSLR's, was set to take images in RAW format ("RAF" files). When I came home, I put the CF card in my PC, copied the whole shebang and euhm... darned! I usually use DPP, but that ofcourse is Canon specific. I lately do my editing on a MAC using Aperture, but Aperture doesn't understand RAF either. So, here began my search for a decent RAW converter. On the MAC, free RAW converters are pretty scarce so I decided to continue on the PC. Here are the contenders I found on the web that looked useful and are pretty well known:
1) S7RAW (specifically for Fuji RAF, this seems to be the benchmark)
2) RAW therapee
3) PICASA from google supports a number of RAW files
4) UFRAW, the defacto standard RAW convertor for The GiMP

You should know that the Fuji is not really a "noiseless" machine, in fact it is quite noisy even at low ISO settings. In the end, I took this shot to test with:
http://www.ausphotography.net.au/gallery/files/1/5/2/3/DSCF1449.jpg
Some parts that are tricky: it is about 1 stop underexposed, it has some really dark parts, some lettering and a logo that is almost out of focus. Note: the paint resembles the pearl-effect paint that is rather popular on new cars around here, so you're not looking at an exceptionally noisy photo - the paint really looks like that!

Another issue: the Fuji has a foveon sensor that spits out 9 MPixels. However, there are tricks to double that to 18 MPixels...

First impressions
Picasa
The first impressions are a mixed bag. Picasa looks very simple (well, okay, it *is* ;)) - there's not too much you can configure. However, the software is very fast and the conversion seems spot on. Just a little tinkering with color and extra sharpening is done to get a decent result. However, Picasa is not color managed and that shows. Further more, it generates JPEGs, nothing else. The resulting JPEG is 3460x2607 pixels and 4,191 kByte large. Standard JPEG compression quality according to Mediachance's JPEG quality estimator is 96%.

S7RAW
This is "the benchmark", or so it seems when checking the Web. The interface is quite busy and looks a little outdated. Opening a RAF is pretty quick (some 5 seconds). The interface is somewhat strange with undockable windows but not that bad. It has all kind of parameters you can fiddle around with, but no "find the best" option. The thing generates a whopping 20 MByte JPEG image at 4896x3688 pixels. With the JPEG quality in S7RAW set to 100%, JpgQ agrees to this 100% quality. Conversion to JPEG however is a multi-step process (automated) that takes almost half a minute on my machine. Not fast at all.

RAW Therapee
Okay, I must confess I had some high expectations from this piece of software. The results I had seen on the net where outstanding. The interface looks modern and well polished, but loading a file is a PITA. There's a small directory selector in the left bottom corner and a preview pane next to it that loads really slow. Loading the RAW file itself is quite slow too and that is an indication of the whole performance of the program: slooooooower than, well, you get the picture. There is a simulated LED in the right bottom corner that turns red when the software is doing something and green when it is ready. And be warned: it is red an awfully long time! The good news: it's color managed and the interface isn't bad. It has an "auto levels" function, a lot of things you can tinker with and a history that keeps everything you've done. It can do sharpening, noise reduction, has full color control and the list goes on and on. Conversion however is surprisingly euhm... fast. ish. 20 seconds it took to convert this image. However, if you have changed more parameters, it takes longer to convert. The result is the largest of the lot (pixelwise) with a 13 MByte output at 4889 x 3679 pixels. According to JpgQ, the output is 100%.

UFRAW + The GiMP
Okay, I admit... this has never been my favorite combination. But I must say, despite its somewhat strangely amateuristic looking interface, it's not bad. It offers all the bells and whistles that you want in a RAW converter and it's color managed. It's pretty fast too. Once you know your way around the clumsy interface (there are tabs on places you won't expect) it is not bad at all! Whitebalance works great, it has some type of noise surpression, it has, well, everything actually. Best of all, it's blazingly fast. It generated a 3460x2607 pixels JPEG that is not too bad at 5,7 MByte. In that size, it still offers a 100% quality.

Ofcourse, the primary benchmark is the Result. Here's an overview from the 4 contenders, 100% logo:
http://www.ausphotography.net.au/gallery/files/1/5/2/3/logo.jpg
You may notice immediately that:
1) Picasa has the sharpest logo
2) UFRAW is quite soft, probably because of its noise reduction
3) RAW therapee has some weird colors
4) S7RAW is blurry but controls noise quite good

Okay, what these don't show is color. So I took another image, this time with lots of color (thumbnails are clickable for larger versions):
http://www.ausphotography.net.au/gallery/files/1/5/2/3/s7raw_thumb.jpg (http://www.ausphotography.net.au/gallery/showimage.php?i=3427&catid=member&imageuser=1523) S7RAW

http://www.ausphotography.net.au/gallery/files/1/5/2/3/rt_thumb.jpg (http://www.ausphotography.net.au/gallery/showimage.php?i=3426&catid=member&imageuser=1523) RAW Therapee

http://www.ausphotography.net.au/gallery/files/1/5/2/3/picasa_thumb.jpg (http://www.ausphotography.net.au/gallery/showimage.php?i=3425&catid=member&imageuser=1523) Picasa

http://www.ausphotography.net.au/gallery/files/1/5/2/3/gimp_thumb.jpg (http://www.ausphotography.net.au/gallery/showimage.php?i=3424&catid=member&imageuser=1523) UFRAW + The GiMP

All that has happened in all packages is set the white balance according to the greycard in the back and resize. Note the difficulties in the red: in reality the glove is really, really red, the pink (always difficult) is harsh pink and the yellow is, you guessed it, quite yellow. Note the differences in what each converter thinks is "grey". UFRAW and RAW therapee both read a color temperature of around 2790K with a tint 0.913 (very, very close to each other), yet the outcome of these two is quite different.

So, the final verdict. RawTherapee seems to be quite a good contender, but it simply is too slow. Good if you have something that needs fine tweaking and you've got a lot of spare time to spend on a single image, but not for anything else. A 4th place. Picasa is simple and the results, when you have a good start, are not bad. A third place there. Second place: S7RAW and UFRAW is a winner to me. Enough control, good color reproduction and some noise control.

Now, all these four don't stack up to Canon's DPP or ACR (maybe), but hey you get what you pay for!

Tannin
29-01-2009, 4:52am
A really useful post, Jev. Thankyou!

Analog6
29-01-2009, 7:21am
Try Fast Stone Image Viewer. I use it all the time and it does a super jon of converting RAW to almost any file type you want. It is slow on my mchine but it's an old one. I just start it overnight if there is a big lot or go and have a coffee!

jev
29-01-2009, 10:19pm
Thanks for the suggestion Odille. I tried FastStone image viewer, but it just doesn't provide the things I expect from a raw converter. There is no way to set whitebalance for example, there is no way to keep the histogram alive in view when tweaking and I was not able to save the changes I made to the RAW file (just change and generate a modified TIFF/JPEG whatever). That makes it rather useless as a RAW converter in my book, but YMMV.

Seven
19-06-2009, 10:22pm
just noticed this one - great tip and wish I found it sooner

ving
22-06-2009, 9:31am
great writeup :)

i havent used any of these tho. I use irfanview. its great on slow machines, and works really well all round. :)