New Diatom Project

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Hobbyst46
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Re: New Diatom Project

#61 Post by Hobbyst46 » Fri Aug 21, 2020 6:39 pm

Amazing variety of diatoms.
Impressed how you hunt and transfer the tiny ones. Apparently for these, the mechanical finger must be very pointed, a ~1um perhaps. My mechanical finger is uniformly thick, ~10um diameter, so can easily pick 50um diatoms, but not the tiny ones.
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

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KurtM
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Re: New Diatom Project

#62 Post by KurtM » Sat Aug 22, 2020 12:01 am

Very nice! One thing I've been wondering is how you get diatoms to 'release' from the needle onto the storage slide. Can't be using adhesive, because then you can't get 'em back off?

Sorry to hear you got hammered by the hurricane, looks like it may be our turn now. And the shed, that sucks.
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

Charles
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Re: New Diatom Project

#63 Post by Charles » Sat Aug 22, 2020 2:36 pm

Hi Doron, Yes there is a nice variety of species in all three fossil diatomite samples. The glass needles do come to a point so I am able to manipulate and pick up the smallest diatom. Perhaps you can also get your fiberglass needles to a point by holding a strand over a low flame with tension to both ends and pulling it. It wouldn't take much for it to start melting and conduct the pull.

Hi Kurt, The damage from the storms was mostly down trees and limbs, no damage to the house. The shed will need to be replaced and we are awaiting the insurance adjusters.

Picking up a diatom isn't too hard although on some, one needs to 'play' with it to pick it up in the right spot. Picking up a diatom in the right spot facilitates the ability to place the diatom where you want it on a keeper slide. Each species has a sweet spot of where to pick it up. I try to just use the point of the needle to pick of diatoms from the side or just under it, carry it over to the keeper slide and drop/drag it into position. Sometimes if you just lower the diatom to the slide and wait a few seconds, the diatom will transfer from you needle to the slide. You also need a clean sharp needle and static free. With static, you see the diatoms just jump on your needle and then it is very hard to place it back down. To remove the static, at the beginning of a session, I will run the needle on the clean part of a glass slide, back and forth and in circles for about a minute. If the needle picks up debris or gets liquid residue from the strew slide and gets dirty, I will put a drop of distilled water on a clean part of the slide and run the needle through the drop several times to get the needle clean and then run the needle on a clean part of the slide to get the water off and dried.

You can see from the below keeper slide, you can be very accurate placing diatoms on a clean slide.
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Charles
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Re: New Diatom Project

#64 Post by Charles » Sat Aug 22, 2020 3:34 pm

For diatom picking up and placing back down, the three YouTube videos can give you an idea how to handle problem diatoms which stick to your needle. You can rub it against the glass slide, you can use a larger diatom to knock it off the needle, you can take it back to the strew, and pick it up differently, or you can flick the needle holder to dislodge the diatom and then pick it back up. It helps to have a platform which can be moved in all directions. That's why I use a large glass plate to hold both my strew slide and keeper slide together, and just move the glass plate to position the needle and diatoms.
https://www.youtube.com/watch?v=0YIsCop ... e=youtu.be
https://www.youtube.com/watch?v=g-F0Id_m3Ys
https://www.youtube.com/watch?v=UlZhqMU ... e=youtu.be

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KurtM
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Re: New Diatom Project

#65 Post by KurtM » Sun Aug 23, 2020 12:52 am

Thanks, Charles. I've seen those (exceedingly nice!) videos and will be watching them again. Your written description is also helpful, and very much appreciated.
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

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