Re: Problems with a dim video

[Samuel Sieb]

On 05/28/2016 08:35 PM, Robert Moskowitz wrote:
> This little trick has stopped working.  Laptop display is dimmed.  I
> should mention that the external monitor is running at max video
> brightness.  On boot, if I <Alt-D>, the notebook video starts bright,
> but quickly dims.

You keep mentioning that the external monitor is bright, but that is 
irrelevant.  There is no way for software to adjust the brightness of an 
external monitor.  Power saving yes, but not the brightness.

Problems with a dim video

[Tim]

Allegedly, on or about 29 May 2016, Samuel Sieb sent:
> You keep mentioning that the external monitor is bright, but that is 
> irrelevant.  There is no way for software to adjust the brightness of
> an external monitor.  Power saving yes, but not the brightness.

That's not exactly true.  While there isn't a way to control the
backlight with ordinary monitor connections, brightness and contrast of
the generated video signal can be controlled.  Of course this gives
worse results than supplying a full signal to the monitor, and adjusting
the monitor controls.  And cannot make a picture more brilliant if
you're using a (LCD) monitor that uses a backlight (that's running dim).

Problems with a dim video

[Robert Moskowitz]

On 05/29/2016 12:43 PM, Samuel Sieb wrote:
> On 05/28/2016 08:35 PM, Robert Moskowitz wrote:
> > This little trick has stopped working. Laptop display is dimmed.  I
> > should mention that the external monitor is running at max video
> > brightness.  On boot, if I <Alt-D>, the notebook video starts bright,
> > but quickly dims.
>
> You keep mentioning that the external monitor is bright, but that is 
> irrelevant.  There is no way for software to adjust the brightness of 
> an external monitor.  Power saving yes, but not the brightness.

Basically I included that information to show that the system was 
driving the external video just fine.  The problem was/is the internal 
monitor.