Changes

Simulates CRT flicker, which is necessary for the human eye to perceive fluid motion. Without it, the sample-and-hold method used by LCDs manifests as motion blur to our eyes. For LCDs, running at 120hz 120Hz with black frame insertion every other frame gives you 60hz 60Hz CRT motion quality on 60fps content.

For CRT monitors, they can use a 120Hz refresh rate to sync to 30kHz (240p 120hz and black frame insertion can get rid of frame doubling on 60fps content, allowing you to use the actual native resolution display mode without shit motion quality for emulation) resolutions.

However, 240p at 120hz 120Hz can create motion blur. The motion blur is , due to having twice as many frames being drawn on screenand overlapping. The solution is to draw a black frame every other frame, slowing down the frame rate to half. At 120hz 120Hz that essentially brings it back down to proper 60hz for emulators60Hz. The issues are that brightness is halved and any frame drops are very noticeable.

In RetroArch there is an option for black frame insertion in the video options in RGUI. This makes it draw an extra black frame for every frame and it succeeds in making the motion smooth at 120hz. There is an option for the swap interval. The only issue is that brightness is halved and any frame drops are very noticeable.[[Category:FAQs]][[Category:Recommendations]]