Colour space

While reviewing the DiMAGE 7 I soon discovered that it was in fact recording images in a custom colour space. The same is also true of the DiMAGE 5. To get the optimum colour balance (and accuracy) it is necessary to run images through the supplied DiMAGE Image Viewer Utility with the 'colour space correction' option selected and sRGB or whichever colour space you work in selected as the output colour space.

Most digital cameras are 'set up' (I'd use the word calibrated, but very few are strictly) to give the best results on sRGB devices (such as your computer monitor) we will be using sRGB for our output colour space in this review, this will also ensure the optimum colour viewing the images in your web browser.

Native DiMAGE 5 image	Converted by Image Viewer to sRGB

This is both a good and a bad thing, it's good because it means that the 5 is able to capture a much wider colour gamut (depth and range of colours) but that to appreciate these you need to either convert them to sRGB or convert them to another colour space and then view them in an image viewer which understands JPEG colour space tags. I would have preferred that this be an in-camera menu option 'Minolta colour space / sRGB colour space'.

I won't repeat myself too much, you can read about this discovery and a more detailed explanation about colour space in our DiMAGE 7 review. Click here for a description of the Image Viewer Utility.

For the record we were the first review to discover and document this fact, it led to an addendum being inserted into the DiMAGE 5 & 7 retail box.

Important review notes

From this point onwards in the review if you see the following text: "Image re-saved to sRGB colour space" you will know that the images / crops of images you are viewing have been run through the Minolta Image Viewer application. Note that NO adjustments other than the colour space conversion are made. I noticed no difference in detail (resolution) between the native and converted images. The Minolta Image Viewer appears to maintain EXIF information.

JPEG/TIFF Image Size & Quality

Standard Test Scene

The DiMAGE 5 offers a wide variety of resolution and image format options. You can choose from JPEG (three compression levels), RAW (unmodified CCD data) or TIFF. In combination with a resolution of 2048 x 1536 (native CCD), 1600 x 1200, 1280 x 960 or 640 x 480.

To give an impression of what some of the combinations of image size and quality produce the table below is a cross reference of some of them:

• 2048 x 1536 RAW
• 2048 x 1536 TIFF ("Super Fine")
• 2048 x 1536 JPEG FINE
• 2048 x 1536 JPEG STANDARD
• 2048 x 1536 JPEG ECONOMY
• 1600 x 1200 JPEG FINE
• 1280 x 960 JPEG FINE
• 640 x 480 JPEG FINE

Images below are cropped 240 x 100 area of the image magnified 200% (nearest neighbour).

	2048 x 1536
RAW	6,254 KB (Not available for download) / (Saved as JPEG 1,238 KB)
TIFF	9,272 KB (Not available for download)
JPEG FINE	1,538 KB
JPEG STD.	787 KB
JPEG ECON.	541 KB
	1600 x 1200
JPEG FINE	957 KB
	1280 x 960
JPEG FINE	680 KB
	640 x 480
JPEG FINE	250 KB

Note that because we're looking here at the quality of the D5's JPEG/TIFF encoder none of these images have been run through the Minolta Image Viewer (except for the RAW image). Overall JPEG FINE very clean being almost identical to TIFF (except that the TIFF image seems to be 'whiter' overall). JPEG artifacts creep in at the STANDARD compression and are clearly visible in ECONOMY mode.

RAW mode produced a noticeably different image, the 'dotted' bayer pattern on the edges of dark lines is unusual and not expected.

Picture Effects

The DiMAGE 5 allows you to control three variables of its internal image processing algorithms, they are colour saturation, contrast and sharpening. This gives the photographer a good range of flexibility in controlling the way the final image will look, or even simply setting up the camera for his preferred balance. Below you'll find samples of the same scene shot with different values for each of these settings.

The DiMAGE 5 provides three levels of adjustment 'plus or minus' the normal (7 in total for each parameter - except sharpening), to give an idea of what these changes can mean examples of the +/-2 settings are shown below.

Picture Effects: Saturation

Images re-saved to sRGB colour space [info]

Saturation -2	Saturation Normal	Saturation +2

It's refreshing to see more manufacturers taking notice that the users of their cameras would prefer control over certain post-processing parameters. The choice of seven different levels means that most users will be able to tune the DiMAGE 5 to their personal colour preference.

Picture Effects: Contrast

Images re-saved to sRGB colour space [info]

Contrast -2	Contrast Normal	Contrast +2

Contrast -2 provides a nicely balanced image with a well preserved 'bottom end' (shadows) and maintains highlights without clipping so much. Obviously a low contrast does have the side effect of making colours look less saturated.

Picture Effects: Sharpness

Images re-saved to sRGB colour space [info]

Sharpness: Hard

Sharpness: Normal

Sharpness: Soft