[RESOLVED] Monitor Brightness

[stin]

I'm looking for a way to adjust the monitor's temperature. There's a program called f.lux that does this, but it doesn't get dark enough. The program I'm writing will be used on a boat and needs to be dark enough so that it's not blinding while driving at night.

Any thoughts?

[PeejAvery]

Temperature does not control brightness. It will only control blue to yellow hue.

[stin]

OK, thanks. Then I'll need to look for ways to change brightness, contrast and temp.

Is it possible?

[HanneSThEGreaT]

One way to change the brightness is to change the Gamma component to give you a feeling that brightness is reduced. Actually the contrast is reduced.

To do this, you'll need the SetDeviceGammaRamp API :

 <DllImport("gdi32.dll")> _
    Private Shared Function SetDeviceGammaRamp(ByVal hDC As IntPtr, ByRef lpRamp As RAMP) As Boolean
    End Function

I am attaching a working project ( in VB 2010 ) with

[stin]

Super cool. I'll take a look at this tonight.

[stin]

I was able to look at it at work, and I think that's going to be part of the solution, but it just doesn't get it dark enough. I think I still need something with the brightness at least.

[HanneSThEGreaT]

I'm afraid that is as good as it will get. I'll try to see what else I can come up with, but the SetDeviceGammaRamp API is sufficient 99% of the time...

[stin]

I'll have to look at in the dark and see what it looks like in practice.

[stin]

After looking at it in the dark, that may be just what the doctor ordered. Doesn't do much with an all white background, but in conjunction with wise color choices for the background could be just right. Thanks a bunch.

[HanneSThEGreaT]

That's great news Glad you came right

Please remember to mark your thread resolved if you feel you have solved this issue; it is explained here :

http://www.codeguru.com/forum/showthread.php?t=403073

[stin]

I know this is marked resolved but I was wondering if there is a similar function to get the current gamma settings? I tried getDeviceGammaRamp, but from what I could tell that returns whether or not the devices is able to change the gamma.

[HanneSThEGreaT]

Hi Stin

Hmm, not sure that there is something, offhand

Could you perhaps explain a bit more what you'd like to achieve then we can hopefully, possibly identify a solution

Hannes

[stin]

The program will allow the user to change their gamma settings and then reset them when they leave. So really I just would like to capture what it's at when they start the program. The one you gave me starts at 14 or 18 which seams to be an arbitrary number.

[HanneSThEGreaT]

I see

We will have to use GetDeviceGammaRamp at Form load, then with the Form_Closing event set it to what was retrieved at Form load. That will reset it to the value it was before the program was run.

Should I try to incorporate this into my previous example for you?

Sorry, this was very sloppy programming on my side, I should have done that initially

[stin]

If it's not too much trouble that would fantastic. Using APIs isn't my forte, and as I mentioned, I tried using the getDeviceGammaRamp, but couldn't get it to work.

Thank you so much for your help.