[mythtv-users] Colour Saturation Problem

Ian Trider iantri at gmail.com
Tue May 31 21:49:16 UTC 2005


On 5/30/05, Brad Fuller <bradallenfuller at yahoo.com> wrote:

>>  Note, however, that the output equipment has to be properly calibrated
>> itself to calibrate the viewing device; if your video card is putting
>> out severely miscalibrated video (you would need an oscilliscope to
> >actually determine what it is outputting, because how you perceive the
> >displayed image depends on your TV's calibration), calibrating your TV
>  
>  Good point. Any instructions on how to calibrate the video card?
>  
>>  to it will of course put your other sources out.
> 
>> Probably best to use a DVD to fix the TV first,
>  always! I use the Video Essentials DVD on a Sony consumer DVD player. 

Sorry for failing to be totally clear.  What I was implying was that
you should use Video Essentials with your DVD player connected
straight to the TV to calibrate the TV's colour (again, assuming the
DVD player isn't stupid and putting out bad colour), and then connect
the DVD player to the capture card, and capture a test image, load it
into a photo-editing program (like GIMP), and use the eyedropper to
verify the values are right (I don't know if gimp will show you the
numbers the right way; the colour bars on the DVD are probably
described as being 75% saturated red/green/blue, or W/E -- I have
Avia. Check the description so you know what you should be looking
for).

Once you know your capture card is good (because they are MISERABLY
calibrated, especially bt878's), you can output that captured test
image that you know to be captured in proper calibration to the TV. 
Adjust the video card's colour/brightness settings until the image
displays (on the TV, which we know to be properly calibrated because
we did it earlier) the way it aught to.

After you've taken all the time to do that, everything should be
decently calibrated (or at least, as best as possible when going by
eye).

:)

-- 
Ian Trider
iantri at gmail.com


More information about the mythtv-users mailing list