Thin Lines Vibrating, Why?
 

I have some footage with some striahgt lines in it creating a strobing effect, which does not look good.

Any ideas why this is happening and how to reduce it?

My guess is its something todo with interlacing?


Cheers,
Ben Gurvich

That's exactly correct. Your raw footage will be difficult to correct to remove this malaise. A very slight Gaussian blur or scaling the clip down a bit or even a pip will eliminate this, but the artistic vision of the scene could be compromised. If the scene is short enough you could de-interlace. Or try the flicker removal option in your NLE. This is easy to get at in Premiere.

If the area strobing is text, use a sans serif font or avoid "font with feet". Arial black , Tahoma and Helvetica are good choices.

If the area is a raster graphic, be sure to use lines of no less than 4 point size. You can also feather larger edges to keep flicker to a minimum.

The above assumes the trouble is during the edit stage. If this persists once you have exported to dvd, perhaps try a different encoder/dvd authoring program. They do come in various shapes and sizes and the quality is variable.

The reason for the flicker is that a thin line can exist (for example) in the odd 60i field but not the even field. Therefore every 1/30 second it flickers on and off.

Which editing program are you using?

In most programs, there is a de-interlace setting/option that can blend or interpolate fields to get rid of the interlace flicker. Blend fields is usually good.
Flicker removal filters are also good.

In Vegas, you can try unsharp mask with negative values (-0.500 amount, 0.005 radius, threshold bout 0.040 or so).