Continuing Yin and Yang with the Fuji X sensor.

Sometimes I think the images from my X-E1 are amongst the best I've ever seen, sometimes, if they happen to contain a lot of smeared similar looking green foliage, I wonder why on earth I bought it. However, spending the last few days in a heavy editing cycle, I've found a way to both deal with that and come to terms with it. You may have noticed that despite all my many reservations about the X-E1, poor battery life, smeary foliage, poor video etc. I still have it and still use it. I expressed some reservations in a previous post about the performance at low ISO's, but I've made an interesting discovery. The more you upsize the files the better the camera / sensor does in relationship to others.

Firstly on upsizing. Below are the sizes offered by iStockphoto on an X-E1 upsized file that is on their website. In pixels and in inches.

As you can see, libraries offer a range of sizes at different prices. Now I know, and the library knows, that the largest sizes are bought rarely and at 36MP virtually never, however it is necessary for myself and the library to be sure that the image is capable of being reproduced at its largest size. It isn't just there as a kind of subliminal hint that this is really a high quality file (honest). Though it is true that getting an image to look good when interpolated (upsized) does make all the lower sizes look better. As you can see, I've been upsizing my X-E1 files to the same size as my Nikon D800E and of course the same size as the upcoming Sony A7r. 

Some have asked me in the past, why do this? The simple answer is because I can. Anyone who has been contributing to and selling via picture libraries from the earliest days of digital knows all about upsizing files. In the early days with 4MP, 6MP, 8MP and even 10MP file sizes, it was actually a requirement that many libraries put on file submission. Many stipulated that the minimum size for uploading was 48MB (before compression) This equates to a 17.5MP file, which as you will realise is close to A3 and something that many cameras available today can't produce without upsizing, including all m4/3 cameras and of course the Fuji X-E1. So those of us who wanted to contribute digital camera images as well as film scans had to learn to interpolate a file with the minimum quality loss and the maximum sharpness. And as camera sensor sizes got bigger, I and others thought, well if it works for a 6MP sensor, why not use it for 12MP, 16MP and 24MP etc.?

With improvements to Photoshop over the years, this upsizing has got easier, quicker and now is capable of producing interpolated images that its very difficult to tell apart from images that are left at the size they come out of the camera. Its not 100% of course and I could best describe the difference between a native D800E and upsized X-E1 file as the first looks like it was taken with a high-quality prime, the second looks like it was taken with a cheap kit zoom. However both are acceptable to picture libraries, since they don't particularly like ultra-sharp files. Firstly because it makes the smaller sizes they create, and which will sell far more than the largest size, look over-sharpened. And secondly because the theory goes that the purchaser of the image will sharpen the images appropriately when publication size is determined. In practice, the latter often doesn't happen and the file is published as is, but that's the reasoning behind the acceptance of 'softish' looking files at their largest size.

So why would the Fuji do this better than other cameras? Well, its true that despite the lack of an AA filter, Fuji X-Trans sensor images are slightly softer than from many of their competitors sensors. Certainly, m4/3 cameras, for example, produce more punchy and sharper looking files (I'm talking exclusively about raw files here. I'm not going into jpgs. since I don't use them for stock uploads, and picture libraries all require images to be shot raw. Though whether or not that's what they get is another matter!) However the very fact that the images from the Fuji sensor are slightly softer means that high ISO is better. Even at base ISO settings m4/3 raw images when processed have visible luminance noise (digital grain) whereas with the Fuji its difficult to spot this even at ISO 800. And yes some of this is software manipulation as well as the quality of the sensor itself, but then all other cameras do exactly the same. So that's one way in which a Fuji 'disadvantage' can become an advantage.

Another thing I've discovered is that Fuji X files look better and certainly upsize better if they have all sharpening turned off at the raw processing stage and when they are finally edited are sharpened very sparingly. I've done lots of experimenting with files from my current and previous cameras and in the vast majority of cases when I compare results, the X-E1 files look better in terms of clarity and lack of noise. I've found for example, that these X-E1 files I upsize from 16 > 36MP look consistently better than files from the Nikon D7100 I had when I upsize those 24MP > 36MP. I was surprised by this, but did a whole series of tests and it was in fact the case. The lack of sharpening also keeps the smeared foliage phenomenon under control as well, as its always exaggerated by sharpening.

When the Fuji X sensor was unveiled around two years ago, I'm sure I wasn't alone in expecting some Leica M9 CCD or Sigma Foveon look to the files. However, its obvious now that C-MOS sensors don't produce CCD type sharpness when the AA filter is removed. In fact, it seems to make a marginal difference at best. It is there, but you often have to look really hard to see it. So, no AA filter doesn't really mean what many of us thought it would mean and I guess its taken me sometime to get rid of my expectations and preconceptions and to stop finally trying to make my X-E1 images look like something they are not capable of. 

What the sensor and the cameras are really good at is producing clean, low noise images. This is obviously an advantage for upsizing. Fuji talked a lot about how their APS-C sensor could produce files that were comparable with images shot on 35mm sized sensors. For some time I just thought of this as yet more blah blah blah, but I'm beginning to see what they are getting at. The closest comparison I can make to what the X-E1 files I'm processing now look like is with an AA filtered DSLR. Fuji may try to style their cameras like Leica's, but there is no resemblance whatsoever to the look of the Leica M digital CCD files of the M8 or M9. The files are much smoother and cleaner that those files. 

So, bottom line is, I've decided to embrace what the Fuji can do well and live with its 'eccentricities'. Certainly, I'm VERY pleased with the upsizing I can get and this may mean that I can avoid buying the new Sony (though don't count on it!) Plus I have a lot of respect for any camera that's managed to produce a self-portrait and new profile image that I can actually live with without phoning up the nearest plastic surgeon. And that's no small thing!

N.B. to see more on the cameras and lenses featured in this post click on the relevant labels (tags and keywords) below.

All original material on this blog is © Soundimageplus

Join the Soundimageplus Blog Readers Group at Google+

For comment and discussion - join me over at Google+

soundmageplus website on prosite (under construction)
soundimageplus on behance