Rheinberg illumination: 2nd attempt

[gekko]

I am not sure whether this constitutes a partial response to The QCC's Rheinberg Illumination Challenge (viewtopic.php?f=9&t=688).

A link to my first attempt at Rheinberg illumination: viewtopic.php?f=25&t=619&hilit=rheinberg+filter+attempt

Here I used a slide of strewn diatoms and a more complex Rheinberg filter. As in my first attempt, I overlaid the center color (blue) stop with a polarizing filter and used another polarizing filter over the light port below the condenser which I rotated to reduce the light intensity of the direct illumination.

1. Rheinberg filter (also rather crudely made, I'm afraid).


2. Bright field image of diatom; 10x objective.


3. Image of diatom using the Rheinberg filter; 10x objective.


4. Image of same diatom using a 4x objective.


5. Image of a "simple" diatom; 10x objective.

[Crater Eddie]

Interesting effects.
It doesn't matter what the filter looks like, as long as it gives results.
CE

[75RR]

Nice Diatom. Like the brightfield (black and white) image most.
Are there several smaller diatoms under it?

[mrsonchus]

Good images, really good strong & clear blue background - a good start I'd say. Interesting 'rainbow-like' effect. Show us more!

[gekko]

CE and mrsonchus, many thanks for your comments.
75RR, I agree with you, but the purpose was to obtain a reasonable Rheinberg effect.

I forgot to add a few comments: (1) the color pattern of the filter was meant to give different contrasting colors to objects at 90 degrees to each other, as can be clearly seen in the last image, where the horizontal parts are red and the vertical green, the background being blue. This can be useful, e.g., in unstained striated muscle sections, for example. (2) The filter was made for the 10x objective, but appeared to work reasonably well with the 4x objective.

[75RR]

75RR, I agree with you, but the purpose was to obtain a reasonable Rheinberg effect.

You are quite right. I did rather miss the point. Sorry!