Re: Green Filter

What type of green filter is it?

If it is a color contrast filter, you can use it to enhance contrast for certain specimen. You most like use then a B&W image sensor.

If it is an interference filter, you can use it for phase contrast illumination to improve the phase contrast effect.

Cheers,

Gregor

PS: The following is from one of my old web pages:

Color Contrast Filters
These filters are chosen to be complementary in color to whatever color in the object is to appear dark on B&W film. For instance, take a red R(25A) filter if you want the blue sky to appear black. Mostly, these filters are based on selective absorption and transmission. The glass filters from HOYA type red R(25A), green G(X0), orange 85B, and yellow Y(K2) are examples.

Didymium Filters
These are special filters to improve the reproduction of certain biological stains (such as Eosin). It is a recommended filter to be used when looking at histology sections with H&E stain. The filters SCHOTT BG-20 and HOYA V-10 are examples.

Color Correction Filters
These filters are used to change the color temperature of of the light source illuminating an object. The glass filters from HOYA type 80A and 80B are examples.

Polarizing Filters
These filters have a preferred vibrational direction and hence transmit preferentially light whose plane of polarization is parallel to a particular axis of these filters. The filters from HOYA type PL and PL-CIR are examples.

Blocking Filters
These filters block frequencies above or below a certain frequency. Examples are UV and IR blocking filters. IR blocking filters are also known as heat filters. The filter SCHOTT KG1 is an example.

Interference Filters
Instead of selective absorption and transmission, these filters function by selective reflection and transmission. The have the advantage of providing a narrow bandwidth and usually avoid the built-up of heat. Green interference filters are an example, which are used for phase contrast microscopy.

Neutral Density or Grey Filters
These filters are used to decrease the intensity of light but keep the color temperature unchanged. The glass filters from HOYA type NDx2, NDx4, and NDx8 are examples.



<sathered@xxxxxxx> wrote in message news:7hvj03dfvg9nh0biqimrnhja3euir6av6q@xxxxxxxxxx
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?

.

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