Strange behaviour when rotating video

[petermidi]

Hi there,
I'd really appreciate a little help with this.
I have a simple little .mov video shot with a digital camera.
It opens and runs happily in my videolan.
But when I rotate it 90 degrees - preferences/filter...
Although the images rotate - the effect is as if they are now black and white, though I can see some of the strong colours from the original orientation ghosting in their original positions - 90 degrees out of wack!
Can anyone help me clean this up please.
Thanks so much.
Peter