Heantun:OK...looks like an authentic 50's bus picture now! Thanks, but I was still trying to get that transition from b&w into colour effect...bit like the opening part of Wizard of Oz, when the mono ilm changes to technicolor (c)...?

Cropped, bus selected, selection inverted, selection grown and feathered, selected area converted to monochrome, resized, overall photo sharpened, bordered.
The attempts at doing a transition really did look weird.
Heantun:
Will try your technique on some pix I have of a hangar dance at an RAF base - should work well with them.
This one...?

Cropped, slight vignette applied, tinted, filmgrain, bordered.

Galleries:
Monochrome :
* of the best