Re: Information re. display gamma

[Richard Hughes <hughsient gmail com>]

On 10 February 2010 22:31, Milan Knížek <knizek confy volny cz> wrote:
> Overall system gamma is a product of image encoding gamma, video card
> gamma and native gamma of the monitor and normally it should be equal to
> 1. You may want to adjust gamma to allow for non-standard viewing
> conditions (e.g increasing gamma in dim light at home). Refer to User
> Manual for more details.
> ---
> And this be included in User Manual:
> ---
> CRT monitors have native gamma around 2.4 - 2.5 and LCD monitors usually
> emulate the same value.
>
> Traditionally, Linux and MS Windows operating systems use image encoding
> of 1/2.2 and do not apply any gamma adjustment to the image or video
> card LUT. Therefore the overall gamma is expected to be around 1.1
> (which is useful to allow for dim viewing conditions at home
> environment).
>
> Apple used to use image encoding gamma close to 1/1.8 to naturally match
> the native gamma of printing devices (and therefore internally applied
> gamma adjustment of 1/1.45 before displaying images on monitor so that
> the images displayed correctly).
>
> Nonetheless, since OS X (v10.6 Snow Leopard) the default image encoding
> gamma has also the value of 1/2.2 to meet the requirements of consumer
> imaging industry.
>
> Before fine tuning the gamma in GCM, you should know what your monitor
> native gamma is, what display gamma you want to reach and then do the
> math yourself.

Sounds good to me. Thanks.

Richard.