Re: [Gimp-user] Seeking better "green screen" method

[Jay Smith <jay JaySmith com>]

On 01/17/2012 03:29 PM, Chris Mohler wrote:
> On Tue, Jan 17, 2012 at 2:17 PM, Jay Smith<jay jaysmith com>  wrote:
> > Goal:
> >
> > To be able to select the background (for change to 100% black) without any
> > "leakage" of the selection onto the stamp objects AND without ANY non-black
> > color artifacts remaining after changing the selection to 100% black.
>
> Question: have you tried scanning with a dark-as-possible background*
> and then doing 'Colors-Levels' and dragging the right-hand slider over
> until the background is "solid black"?

Yes to "dark as possible" (and not shiny)

No to "Colors-Levels....".  The problem in that operation is that it 
would also affect the related black areas in the postmarks on the stamp. 
 The color of the postmarks should not be darkened as it would change 
the appearance of the image (which are actual items that people are 
expecting to appear in the image as they are in real life).

> Also, the "halo" may be a result of the height of the objects/stamps -
> have you tried adding weight on top of the objects to get them as flat
> as possible?

I agree that height/thickness is part of the problem.  Yes, we have 
added weight with no affect on most items.

Please note that the "weather person standing in front of a weather map" 
has not only their own thickness, but a foot or two between them and the 
map.  If the room lighting is not 100% right, one can see a bit of 
"green screen shadow", but 99% of the time there is no shadow and no 
halo.  I am hoping that level of success can be achieved in what I am 
trying to do.

Thank you Chris.

Jay

> Chris
>
> * something black, with a non-reflective surface.