2009 HDTV conversion.

[old_tv_nut]

Originally Posted by peverett

I was finally able to check digital TV reception at ...
I have noticed one repeating artifact in both satellite and digital TV. If a car such as my 1963 Falcon is on the screen, the slotted grill causes a rainbow effect. I have seen this on several items with slotted type surfaces, including railroad cars and dress ties.

This is an old well known NTSC artifact called "cross-color" - where high frequency luminance details (lines or sharp edges) get into the color circuit and are demodulated as flickering color information. A comb filter reduces this greatly, but not on diagonal lines. It does not occur in purely digital systems, but can be seen when the digital signal is converted to NTSC for existing sets. (Or, sometimes, if the original signal fed to the digital system comes from an NTSC source, it may appear in the digital signal from that point onward.)

[andy]

Originally Posted by old_tv_nut

This is an old well known NTSC artifact called "cross-color" - where high frequency luminance details (lines or sharp edges) get into the color circuit and are demodulated as flickering color information. A comb filter reduces this greatly, but not on diagonal lines. It does not occur in purely digital systems, but can be seen when the digital signal is converted to NTSC for existing sets. (Or, sometimes, if the original signal fed to the digital system comes from an NTSC source, it may appear in the digital signal from that point onward.)

If the set has an S-video input, it should eliminate the problem.