dark field filter

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Maryfox
Posts: 57
Joined: Fri Jan 04, 2019 5:10 pm
Location: Florida, USA

dark field filter

#1 Post by Maryfox » Fri May 22, 2020 6:06 pm

A small success! I made a dark field filter! Watching the video 🔬 Making microscope filters: Darkfield, Rheinberg, Oblique
I gave it a try and it worked. https://www.youtube.com/watch?v=Pku4T8s ... x=6&t=623s

You may now go back to your regularly scheduled program.

Hobbyst46
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Re: dark field filter

#2 Post by Hobbyst46 » Fri May 22, 2020 9:26 pm

I would love to see your results !

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Maryfox
Posts: 57
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Location: Florida, USA

Re: dark field filter

#3 Post by Maryfox » Sat May 23, 2020 1:34 pm

I cut a circle of semi-rigid plastic using a filter as a template. Somewhere on the net I read about a "dime" filter so I cut a circle the size of a dime from black paper and attached it using double-stick tape. It ain't pretty, but it works. I'm looking forward to playing with this. Here's my first experiment at 4x.
Attachments
First darkfield experiment.jpg
First darkfield experiment.jpg (119.06 KiB) Viewed 2714 times

Hobbyst46
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Re: dark field filter

#4 Post by Hobbyst46 » Sat May 23, 2020 5:56 pm

Thanks. Looks promising !

MicroBob
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Re: dark field filter

#5 Post by MicroBob » Sat May 23, 2020 6:49 pm

Hi Mary,
I have one suggestion: Dark field images are difficult for camera light meters to handle as the meters are tailored towads an averagely lighted image. This leads to an over-exposure of dark field images. So the results are usually improved when an eyposure compensation of 1-2 stops is dialed in. This leads to a pitch black background and highlights that still contain detail.

Bob

DonSchaeffer
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Re: dark field filter

#6 Post by DonSchaeffer » Sat May 23, 2020 7:34 pm

I would suggest closing the condenser a little. It looks like your bright areas are overexposed.

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Maryfox
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Location: Florida, USA

Re: dark field filter

#7 Post by Maryfox » Mon May 25, 2020 12:59 pm

Thanks, folks, for the suggestions. I use an eyepiece camera so the only adjustment is via the camera's software. But I can vary the condenser. Again, Thanks.

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