Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, Alan King <alan@n...> wrote:
> Steve wrote:
> 
> > 
> > I'm really confused. Black areas are where copper is.
> 
>    Exactly.
> 
>   But black areas
> > over the emulsion result in it washing away.
> 
>    Again exactly.
> 
>   This isn't making sense
> > to me.
> 
> 
>    If black areas are where the copper is, but instead you need black 
> areas over what to remove, then you need a negative of the copper areas 
> image to expose the emulsion. 

Well, I was answering Tom and he said:


> Most screen printing emulsions are negative acting. Expose them using
> a postive image of your circuit board where opaque black is the
> copper and clear areas are etched away.

Which doesn't make sense. What -you- said makes sense. Use a negative
image with negative resist.

Steve