Re: Green Filter

Rainer Teubner wrote:
Hello,

the green filter is for illumination for phase-contrast according to Zernike. As the human eye has its maximum sensibility in the green part of the optical spectrum, chromatic errors of the achromatic objectives are minimised ba the green filter.

Kind regards

Rainer Teubner

sathered@xxxxxxx schrieb:
I have a microscope which came with a blue and a green filter. I use the blue to
create a white background. I can find anyone that knows what you would use the
green filter for. Any help?


The green filter is used for B&W (film) photography, especially when using achromatic objectives. Black and white photographic film has a different sensitivity for the colour spectrum than the human eye (and no 'correction in the brain'). The chromatic aberrations of an objective will be more visible in an B&W photo, than what appears when we look through the oculars.
A green filter is used to reduce the effects of chromatic aberration.

PS: I'm not sure of the differences in practice between using Pan-chromatic or Ortho-chromatic B&W film, the latter is not sensitive to red light.


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