Polarizing Chemicals/Crystals

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houstontx
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Polarizing Chemicals/Crystals

Post by houstontx »

What are somechemicals (other than the usual suspects, vit c, citric, salicylic, vit b12 etc.) that provide interesting images when polarized? I have access to many common lab chemicals and solvents(titrants, indicator dyes, salts etc) along with pure solids.

Maybe someone already has a list on the web somewhere?

Thanks,

Harald
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Post by Harald »

Hi there houstontx,
I´ve used Resorcinol with great result.
Both with sterile water and 60% alcohol.
Kind Regards
Harald

Lier Fotoklubb / NSFF
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zzffnn
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Post by zzffnn »

I searched before but did not find such a list. But I heard thick preparation would give more vibrant colors.
Selling my Canon FD 200mm F/2.8 lens

houstontx
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Post by houstontx »

Ok I found some butylatedhydroxy toluene (BHT) and benzoic acid. Dissolved in Isopropyl alcohol and ethanol respectively. The first two pics are BHT the other two benzoic. Right off the bat I put a couple drops of bht on the slide and they immediately crystalized underneath the cover glass. This was the only slide to do that, all the rest the crystals grew out from under the coverslip and along the edges. I need to research how to make a thin layer of crystals under the cover slip, this is definitely an art form.


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houstontx
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Post by houstontx »

And sorry about the phone pics the Toupeview software a 5mp usb camera does not impress.

zzffnn
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Post by zzffnn »

^ Make a thick layer, it will look even better than a thin layer. Sandwich a cover slip or two between slide and top cover. Or with low NA 4x -10x, you don't have to have cover slips during crystalization (you can add cover after crystals have formed).
Selling my Canon FD 200mm F/2.8 lens

houstontx
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Post by houstontx »

Fan,

I tried a thick layer, it seemed that when there was thick layers or clumps of crystals the colors decreased or were non existent. I think the crystal growth type (needles, plates etc) determines amount of bifringence.

Also these were at 10x, maybe I just won't use a coverslip, and do a streak of liquid, kind of like bacteria colony plating on a petri dish.

Greenfields
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Post by Greenfields »

houstontx

Lots of articles and examples here:

http://www.microscopy-uk.org.uk/mag/lib ... larisation

Henry
Feel free to edit my images.

houstontx
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Post by houstontx »

Henry,

Just what I was looking for, tons of good info! Thanks!

Olympusman
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Resorcinol

Post by Olympusman »

Resorcinol makes a very good melt slide. I would recommend trying various chemicals dissolved in water and then dried on a slide. You may be surprised at what you find.

Mike
Michael Reese Much FRMS EMS Bethlehem, Pennsylvania, USA

houstontx
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Post by houstontx »

I don't have any resocrinol in the lab (1,3 Benzenediol). I did manage to melt some Biphenyl into Isopropyl and make a slide...

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houstontx
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Post by houstontx »

FYI these were all taken at 10x with an olympus A 10. I am using a polarizing filter on top of the slide instead of above the objectives. Hopefully I can fix that soon so I can take higher mag pics.

Also I took a drop of my fish tank algae at 10x, looks really cool under pol lighting. Really can't wait to get higher mags with that...

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