Re: Apple II Colour --> RGB

[spam@luddite.ca (Ned Ludd)]

Andy McFadden <fadden@fadden.com> wrote:

> Ned Ludd <spam@luddite.ca> wrote:
> > Thanks, but what I neglected to mention is that I'm looking for #XXXXXX
> > RGB values, such as are used in html docs. 
> 
> They are.  They're just 12-bit values rather than 24-bit, so you have to
> change $N to 0xNN.  For example, "Orange" changes from $0F60 to 0xff6600.
> 
> The colors you came up with are very similar, though there are some
> differences.  There is some question over whether these values are "out
> of gamut" for NTSC, meaning that they're valid if you're pretending to
> be an RGB monitor but not quite right if you're trying to look the way
> an Apple II does on a television.
<snip>

Thanks, I'll give those a try. However, I think I may be approaching
this all wrong...
My plan was to convert photographs to HI-RES or DOUBLE HI-RES screens by
first saving them in .gif format and then opening them in II.GIF. So far
the results have been hideous.

Here's what I'm doing in more detail:
   (In Photoshop)
 - Scan photo; crop/resize to 280x192 pixels.
 - For colour pics, resize again to 140x192 with "nearest neighbour" 
   resampling. Resize back to 280x192 to "stretch" pixels.***
 - Save as GIFF file using colours indexed to match A2 output.
 - Transfer GIFF files --> Apple II.
 - Convert to HGR or DHR in II.GIF
 - Go back to the drawing board ;-)

What I'm finding is that II.GIF does a fine job of approximating some of
the colours, but is way off on others.

*** The pixel-stretching seems to help a bit, my understanding is that
    colours produced by combinations of two adjacent pixels, so I've
    included this step to minimize noise.

Anyone have a better plan?

Simon