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Gamma Differences Between Platforms and Specifications

Most of the image quality problems experienced in digital photographic imaging are due to the difference in the default viewing gamma between different platforms.    

Printer and camera manufacturers often embed gamma tweaking into their products. This helps the manufacturers, they do not get many complaints about dark images. Historically the amount of this gamma tweaking has followed the system that has been the the most popular in digital photographic imaging.    

Not many years ago the main platform for digital photographic imaging was the Mac. It is said that the default system level gamma at 1.8 (but accurately it is 1.72). So most of the printers were manufactured with the gamma 1.8 (or 1.72) tweaking in their software.     

Now the boom is with PC system that have the default system level gamma at 2.5. This time manufacturers need to think a bit since a gamma 2.5 space would give very poor printing results. So a gamma space 2.2 known as the sRGB is now proposed, even if there is no platforms that has this gamma. Such compromise results tonal and hue errors. The sRGB proposal: A Standard Default Color Space for the Internet  - sRGB   is supported by Microsoft and Hewlett-Packard. Lately Corel and Pantone have joined it.  

sRGB is bad for the image quality, it specifies a gamma 2.2 space. Please see the damage it does to the image data, and examples of the errors that are generated when such gamma compensated images are enhanced are here.  Unfortunately it is rather difficult to show the degradation that happens when such images are printed, it is much more notable than on monitor.

Here is an example of a linear image.  It appears well on calibrated monitors. It is not degraded by any gamma compensations so this image has the best printing quality when properly compensated for the printer.   It appear as dark and heavily saturated on default (uncalibrated) Mac and PC monitors.
This is the same image but a compensation for monitor gamma 1.8 is applied. This image appears well on Mac monitor with default setting.   If you are viewing this on a Mac then compare this image to the gamma 2.2 compensated sRGB image below. The sRGB image appears to be a bit washed out, it lacks saturation. The background hue of the sRGB image changes to specular white.
Again the same image but a compensation for gamma 2.2 is applied. This image does not appear well on any platform but it is the gamma space of the sRGB specification.
Again the same image but a compensation for monitor gamma 2.5 is applied. This image appear well on PC monitor with default setting.     If you are viewing this on a PC then compare this image to the 2.2 compensated sRGB image above. The sRGB image appears to be flat and a bit dark. The background of the sRGB image is a bit muddy.

If this proposal is accepted then all the consumer grade devices (printers, cameras and scanners) will be set to this 2.2 gamma space. So it will not be only for the Internet, it will affect all the consumer grade product.    

Not all digital images are meant for the Internet. Some are printed, some are displayed on gamma 2.5 systems, some on gamma 1.8 systems and some gamma 1.0 systems.  There is no platform that has the 2.2 gamma space as the default, so the sRGB is inaccurate by definition.   

Note that the sRGB will not affect professional digital photographic imaging systems, because there gamma compensated images are not accepted due to the damages it does.  

To conclude the sRGB proposal is a compromise that truly is not needed, it only degrades the image quality. The most simple thing for the manufacturers to do would be to provide a gamma space selector in a dialog of the driver software, to allow the user to use the most appropriate and accurate setup for his/her system.