I have a lumagen radiance XS which I’m feeding 480i into HDMI 1 from an analog devices eval-7842 board. My question relates to correctly zooming in on a 4:3 Laserdisc image using the “crop top left” and “crop bottom right” function. I need to use this as the Zoom function doesn’t provide fine enough control.

My question is, when using LBOX aspect ratio, how do you maintain consistent aspect ratio across the horizontal and vertical? For each point you stretch the left and right do you stretch the top and bottom an equal number of points? I ask because in the manual it states horizontal adjustment is in pixels and vertical is in scan lines which aren’t equal (I think). Any suggestions to keep these in sync like the zoom function does?

Normally I would use the zoom on 4:3 but I have a slight shift to the left of the whole image and full zoom leaves a black bar down the right side of the screen. I’ve got round it by masking out known full screen aspect ratio using the C2 then switching input to the Lumagen to use crop function. Just wondered if there was a less crude method.