How can one improve polarization?

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Plasmid
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How can one improve polarization?

#1 Post by Plasmid » Mon Nov 23, 2020 3:56 pm

I started to play with the polarizing kit on my Microlux, and notice that at higher magnifications 20x and above the effect is not that noticeable is there a way to improve the polarization effect? Does the condenser need to be as far up as possible what about the iris diaphragm? I keep getting mixed results when playing with the settings. Thank you
Stentor 20x Objective
https://youtu.be/ULRtgDrGaus
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BramHuntingNematodes
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Re: How can one improve polarization?

#2 Post by BramHuntingNematodes » Mon Nov 23, 2020 4:01 pm

Do you have both a polarizer and an analyzer wet up? The effect is not subtle.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination
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Plasmid
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Re: How can one improve polarization?

#3 Post by Plasmid » Mon Nov 23, 2020 4:39 pm

Yep, both are up, the effect can be graded by rotating the lower filter, and is very visible at lower magnifications but use the 40x and it starts to look like oblique mire than polarization which i don't understand, the manual calls for the condenser Iris to be fully open.
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BramHuntingNematodes
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Re: How can one improve polarization?

#4 Post by BramHuntingNematodes » Mon Nov 23, 2020 4:42 pm

Can you obtain extinction?
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination
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Greg Howald
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Re: How can one improve polarization?

#5 Post by Greg Howald » Mon Nov 23, 2020 5:50 pm

Something is wrong. White light is most likely passing the polarizer on the sides causing an oblique mess.
Experience says close down the diaphragm any way no matter what the book says. The book is not you and does not have your equipment. So try that.
Greg
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Plasmid
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Re: How can one improve polarization?

#6 Post by Plasmid » Mon Nov 23, 2020 8:22 pm

BramHuntingNematodes wrote: ↑
Mon Nov 23, 2020 4:42 pm
 Can you obtain extinction?
Yes, I think It was user error, I was lowering the condenser more than I should had.
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Plasmid
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Re: How can one improve polarization?

#7 Post by Plasmid » Mon Nov 23, 2020 8:25 pm

Greg Howald wrote: ↑
Mon Nov 23, 2020 5:50 pm
 Something is wrong. White light is most likely passing the polarizer on the sides causing an oblique mess.
Experience says close down the diaphragm any way no matter what the book says. The book is not you and does not have your equipment. So try that.
Greg
Hi Greg , close the condenser iris or kholer iris? With that being said do i have to reposition the kholer diaphragm after revolving each objective?
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Plasmid
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Re: How can one improve polarization?

#8 Post by Plasmid » Mon Nov 23, 2020 8:27 pm

I was able to rotate through all the objectives an maintain polarization. :)
I guess some samples don't reflect the light like others as in the case with that Stentor.
What do y'all think!
https://youtu.be/ljoTuO1RZiY
https://youtu.be/Igl2MuLf6RI
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Greg Howald
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Re: How can one improve polarization?

#9 Post by Greg Howald » Mon Nov 23, 2020 9:51 pm

I think you did a great job! And it's nice to know that someone else's pond water is as cluttered as mine.😃
Greg
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Plasmid
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Re: How can one improve polarization?

#10 Post by Plasmid » Mon Nov 23, 2020 10:24 pm

Thank you Greg.
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