RE: time to get digital camera?

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Hi Art,

Wow, I had no idea that there is some genetic basis for this weirdness in
seeing color,  I also didn't know that there were different types, learn
something everyday here on the list!


Regards,

Chip Louie
>
>
> There is a huge distinction between color blindness and what Chip was
> referring to, which is 1/10th of 1% of the population which has what
> might be called super color perception.
>
>
> Although you obviously know a lot about digital capture sensors, and I'd
> love for you to give me a good explanation, as I requested in a prior
> posting, you should keep away from genetics... (I was a premedical
> student in University and emphasized genetics) As you can see from the
> explanation I wrote in this newsgroup in August, you've got it backwards.
>
> About Color Blindness:
>
> There are a number of different types of color blindness, or color
> deficiency, a preferred term. (Daltonism is the red-green variety, the
> most common type)  Each has specific (and different) organic causes,
> which are genetic in origin, and are sex-linked, in this case, the genes
> for the condition are carried on the X chromosome, making males more
> vulnerable to it, since they only have one X chromosome, and therefore
> it cannot me masked by a dominant gene if their X chromosome carries the
> color deficiency gene.  Since females have two X chromosomes, if either
> is a dominant "normal" gene for color perception the color deficiency
> gene is masked.  All color deficient males pass on that gene to their
> female offspring since it is on their X chromosome, which may or may not
> be masked depending upon if the X chromosome from the woman's side has
> the color deficiency gene or not.
>
> A woman who manifests color deficiency herself (which means both her X
> chromosomes carry the gene) can only produce color deficient sons.  If
> she carries the gene but it is masked by a "normal" gene on her other X
> chromosome, approximately half of her sons will manifest color
> deficiency. Female offspring possibilities get more complex and depend
> upon both the male and female parents. However, no female offspring can
> manifest color deficiency unless the male in the pair has it, even if
> the female of the pair carries the color deficiency gene on one of her X
> chromosomes or actually manifests color deficiency.
>
> So much for Genetics 101.
>
>
> Kennedy McEwen wrote:
>
>  > In article <FIEDJBDDEKPHGJMLCCCLMEDHCKAA.chip@thelouie.org>, Chip Louie
>  > <chip@thelouie.org> writes
>  >
>  >>
>  >> Hi Art,
>  >>
>  >> There is a pretty large range of what people can perceive in terms of
>  >> color.
>  >
>  >
>  > <snip>
>  >
>  >> Also generally women have about
>  >> twice the chance to be able to see and reliably make these
> distinctions.
>  >
>  >
>  > The gene for colour blindness is carried on the Y chromosome - and so
>  > passes down the male line of the population, not the female line.
>
>
>
>
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