Matt,
I suppose you may be able to find a set of filters that
when integrated over each passband yields equal energies
for each channel (Chucks set is slightly out of balance).
The point I was trying to make was that a three band
detector cannot preserve the appearance of arbitrary spectra.
If you find a solution for the OIII lines, there are
other lines that will be recorded incorrectly. This
doesn't mean we should give up, obviously RGB imaging
has been extremely successful over the last century!
I'm just pointing out that the perfect solution will
elude us.
Thor.
> -----Original Message-----
> From: Matt Thomas [mailto:m-e-thomas@home.com]
> Sent: Tuesday, November 27, 2001 5:02 PM
> To: Thor Olson
> Subject: Re[2]: [APML] Filters and emission (was OK - here's your blue
> Veil N ebula)
>
>
> Thor,
>
> TO> effect with continuous spectra. Consider an "E" source
> (flat spectrum),
> TO> which would appear white to us. Your filters would capture the
> TO> energy from the transition regions twice, the result being an
> TO> excess of cyan and yellow. This would not balance nicely
> to white.
>
> I disagree. Remember you are just capturing intensity through each
> filter, not the actual color through each filter. Thus, a pure
> white source would record equally through all three filters. When
> mapped to Red, Green, and Blue would give you pure white.
>
> Think digitally. A image taken through any of the filters, exposed
> to maximum would produce a value of 255 (8 bit) for each channel.
> Obviously 255 in each color gives you pure white.
>
> -Matt
>
> Tuesday, November 27, 2001, 2:40:29 PM, you wrote:
>
>
>
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