Anyone know what Gamma & Luma delay are? (1 Viewer)

[Jim Mcc]

In the setup menu for my Yamakawa 288 DVD player, there are settings for "Gamma" and "Luma delay". Does anyone know what these settings mean or what they do? The owner's manual does not explain them, or say what the default setting is. Any advice? Thanks.

 

[ChristopherDAC]

"Gamma" refers to a nonlinearity factor which is applied to video because CRTs, both camera tubes and kinescope tubes, have a nonlinear light vs. current relationship. Basically every video system in the world, analog or digital, is set up to handle signals with a gamma of approximately 1.5, and unless you had catastrophic display-calibration problems there would be no reason to mess with this setting.
"Luma delay" is just what it says, a time delay applied to the "Y" or brightness video channel. Its purpose is to allow you, if necessary, to compensate for the fact that some displays [chiefly through a composite connection] will delay the colour signal, so that the colour in the image is shifted slightly to the right which can be annoying. Again, there is normally no reason to mess with this. Probably the default value is "0".

 

[Jim Mcc]

I checked the Gamma and Luma delay settings further, and the Gamma options are: Low, Medium, High, and None.
The Luma delay options are: 0T and 1T. What do you think I should set them at? I don't know what the default setting is, and I don't think I ever changed them. Do you think the default settings are Gamma:None, and Luma delay: 0T?

 

[ChristopherDAC]

Probably, though the default for Gamma may possibly be "Medium". Whatever they're set at now, don't change it unless you are having a serious problem with your viewing. "T" by the way refers to the digital clock period at the output.