Re: [APML] Nikon 600 f/4

[Chris1011@aol.com]

In a message dated 11/8/2001 11:16:48 AM Pacific Standard Time, lthuedk@pe.net writes:


> Though Roland
> Cristen couldn't find the term in any optics literature doesn't mean
> the term doesn't exist. 


The term is not applied to optics, rather to the final image that you assemble from the detector, be it film or CCD/filters. It is here where you introduce weighting to the various colors that result in a "color balance".

>>Its everywhere and it is self-descriptive.
> Some people, including myself, who have looked through a Takahashi
> notice a shift in colour balance toward warm yellow and know it wasn't
> caused by filtration. Or was it?


In the case of a Tak Fluorite doublet, the reason things look yellow or "warm" is because the far blue light is not in focus. It is certainly not because the light is filtered out - it is not filtered, just not in focus. If you want to understand this further, I can Email you two images of Jupiter that show by simulation exactly what is happening when all the colors are not focused at the same plane.

Roland Christen