A stain problem

Question

Okay, I have a big problem with some of the stuff I shot the other day. I didn't clean the screen of my camera and I think there was particles on it because all my shirts turned out like the one below, with that brighter spot on the upper right of the screen (the bright spot on the hair)
Heres a closer look at it incase you didn't spot it.
What is the best way to completely remove that annoying brighter spot?

Answer 1

(as in actual footage of a white or grey card before doing a white balance?)
actually a frame or two AFTER you do the white balance....I assume that was just a typo.
Anyway, congratulations on pulling the lumakey and making a defect matte.
Now you have two clips, your original, and a still (defect matte) which is all black
except for a blurry grey blob right where the lens dirt was. Put that matte on your
timeline somewhere out of the way, make a copy of it, and apply
the Channel > Invert filter to the copy.
I assume that your original clip is in the timeline already on V1.
Shift-option-drag it up to V2, and release the option key before you release the mouse button.
Now you have two copies of the clip in perfect sync.
On the V1 clip, apply the Channel > Compound Arithmetic filter,
and set it to Multiply. See the little drop zone called Layer?
Drag the inverted defect matte into that box. You should see
a little image of the inverted matte in there.
On the V2 clip, apple the same Compound Arithmetic filter,
set it to multiply, and drag the (non-inverted) defect matte to its drop zone.
Set the Composite Mode of the V2 clip to Screen.
Now when you look at the doubled clips, they should
add together perfectly and it should look just like the original.
(There might be a little extra overall fuzziness if you need to render.)
Now try adding the Image Control > Brightness & Contrast filter
to the V2 layer. Try pulling down the brightness a little.
You should be able to see how it makes the blob a little less
noticeable. OK?
OK, now delete the Brightness & Contrast filter, and replace it
with the 3 way Color Corrector filter. Work with the levels
(the little sliders below each color wheel) and dial out the blob.
You can start with the mids, get them right, then tweak the
blacks to avoid having a ring.
Good luck!