Oh right. But I can only do that after I have my sequence though. I want to see it all in black and white and high contrast whilst I am editing, is this not possible then?
You can set up the b/w / contrast effects on one clip and then copy (CTRL+C) the effect,
then as you add a clip to your cut, paste the effect to the clip (CTRL+V).
You can also paste the copied effect to multiple clips at once by applying the effect(s)
to a single clip then selecting that clip in the timeline, right-click and select
'Copy', then select all of the other clips to which you want to apply the same effects,
right-click and select 'Paste Attributes'.
As a cumbersome alternative, you could create nested & effected sequences
from your source material and use them as your source clips as you edit.
It would be nice if Premiere included 'Adjustment Layers' like After Effects.
This would make a good feature request.