Output image file quality / JPEG artifacts

Standard Test Scene

The S3 Pro provides two JPEG compression levels (Fine and Normal) in combination with four image sizes (12, 6, 3 and 1 megapixel) as well as RAW mode. The RAW file size (.RAF) depends on the dynamic range mode selected, in standard mode file will be approximately 12.5 MB, in wide dynamic range mode the file will be approximately 25 MB (as twice the data is recorded). Because of the honeycomb layout of the SuperCCD sensor there is no real 'native' direct pixel-for-pixel output, however the six megapixel (3024 x 2016) should be seen as the nearest size to the input pixel count.

Below you will find crops of the same 240 x 180 portion of the center of a sequence of images taken at some of the available combinations of image size and quality. Crops shown are at 100%, saved as extremely high quality JPEG. The RAW file was converted to a TIFF using Fujifilm Hyper-Utility 2 (ver 2.3). All shots below were taken in Wide dynamic range mode.

4256 x 2848 CCD-RAW (Uncompressed), W-Dyn
25,049 KB .RAF (not for download)
4256 x 2848 JPEG (12 MP) Fine
4,532 KB .JPG
4256 x 2848 JPEG (12 MP) Normal
2,262 KB .JPG
3024 x 2016 JPEG (6 MP) Fine
2,861 KB .JPG

3024 x 2016 JPEG (6 MP) Normal
1,396 KB .JPG

2304 x 1536 JPEG (3 MP) Fine
1,718 KB .JPG

With such large image sizes and fairly small crops it's quite difficult to see artifacts, a closer inspection (a 'pixel peep') of the entire image revealed no JPEG artifacts with the Fine setting but some in Normal (as well as a slight softening / JPEG smearing of image detail). We would therefore recommend everyone sticking to the Fine setting unless they wish to shoot RAW (disadvantage: very big files).

Color space

The S3 Pro provides independent selection of output color space, you can select from sRGB or Adobe RGB. Images taken in the Adobe RGB color space have their filename prefixed with an underscore (_) which complies with DCF 2.0 (Exif 2.21). *

As you can see from the samples below (switch between the two by moving your mouse over the labels) Adobe RGB mode doesn't affect the gray balance of the image but does deliver a very different color response, most notably deeper blues and paler reds (although greens remain unaffected). This is a fairly dramatic difference, the only thing we can conclude is that in sRGB mode the camera is applying some additional color mapping (for that Fujifilm 'pop') which doesn't happen in Adobe RGB mode. Anyone who finds the S3 Pro's standard sRGB color too saturated could perhaps try Adobe RGB.

sRGB Adobe RGB (converted to sRGB)

* This DCF naming convention makes it difficult to keep your images in the correct order if you don't routinely rename them by date/time. A suffix would have been far better.

Color space: CIE u'v' Color Distribution chart

Note that in these samples the Adobe RGB image has not been converted to sRGB and so to view it correctly you will have to load it into a color space aware photo application and assign the Adobe RGB color space. Below each sample is the CIE u'v' Color Distribution chart; larger gray triangle approximately represents the range of color which the human eye can resolve, the inner triangle the available gamut in each color space (sRGB or Adobe RGB).

Again you can clearly see the difference between sRGB and Adobe RGB in the CIE charts, while blues and greens remain close to the limits of gamut reds are paler.

sRGB Adobe RGB