i was at an av company for testing, they didnt propose a hum eliminator. They told me it was the nature of the screen quality. Strange... . It was only one monitor and we will use 20, so i will certainly need something.
The trembling looks like with a computer CRT when the refresh rates is going for example from 85 to 75 to 60Hz.
Output resolution : first tried 720x576 mix size and then 800x600. The image stayed the same with the apple-video adaptor but when connected with the scan convertor we could fill the whole screen but only with res set to 800x600 because we could the manipulate the over-underscan things.