Diatom Search #2
Diatom Search #2
So how you finding diatoms? I have a small pond near here and I’m not seeing them. Now the better microscopes are not assembled right now, so I’m using a light weight Nikon student one with a cheapo camera, but still looking at a reference slide I should be able to see some structures if they are there.
Procedure: Reach in pond pull out rock a foot deep and also scrap off rock at water level. Both get green particles and rock grit. Let it settle and pipette out of the mass at bottom in to a petri dish to search.
So far found a little round guy that moves around a lot. And also found some long guy that I don't know if he's doing much anymore.
Procedure: Reach in pond pull out rock a foot deep and also scrap off rock at water level. Both get green particles and rock grit. Let it settle and pipette out of the mass at bottom in to a petri dish to search.
So far found a little round guy that moves around a lot. And also found some long guy that I don't know if he's doing much anymore.
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- WIN_20210404_11_35_48_Pro_1K.jpg (45.86 KiB) Viewed 2617 times
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- WIN_20210404_11_38_13_Pro_1K.jpg (34 KiB) Viewed 2617 times
Re: Diatom Search #2
I'm trying to follow this procedure, but I don't have a river area near by. I can try an ocean area by the large rocks:
https://www.youtube.com/watch?v=Cp9ym5M0RUc
https://www.youtube.com/watch?v=Cp9ym5M0RUc
Re: Diatom Search #2
Hi,
many diatoms are very small, smaller than e.g. 30µm. To see them you need a sharp image and for this a well made slide. Which microscope and objective are you using, how is your lighting set up and do you use a cover slip?
Bob
many diatoms are very small, smaller than e.g. 30µm. To see them you need a sharp image and for this a well made slide. Which microscope and objective are you using, how is your lighting set up and do you use a cover slip?
Bob
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Re: Diatom Search #2
It is hard to tell based on the picture, but I believe the first pic is of some midge larvae. Maybe Chironomid?
Re: Diatom Search #2
To set the scaling, here is a Klaus Kemp slide done at 4x and 10x on this NikonSE with a mercury bulb that's probably on its last leg:
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- 10X_1K.jpg (35.9 KiB) Viewed 2585 times
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- 4X_1K.jpg (34.26 KiB) Viewed 2585 times
Re: Diatom Search #2
The first were baked onto a coverslip. The second batch shown in this thread (Excluding the Klaus Kemp slide) are in a petri dish as I'm just trying to find anything at this point.
So how Kemp is using a tiny hand held by the pond to look as he collects, so I thought this cheapo Nikon that I might battery power with an LED could be used for that. Maybe I'll see if I can find a plastic hand held off Amazon. But right now, I just some algae built greenhouses and start from there.
Re: Diatom Search #2
The diatoms on Kemps slide are of the bigger variety. So if you wan't to find diatoms and there are only small ones you will need a better combination of magnification and image quality. For sample collecting I would suggest to make a sieve from 25-50µ stainless mesh to be able to concentrate the sample. Then just place a bit of sample and a water drop on the slide and cover it with a cover slip, adjust condenser and look for diatoms with 10:1, 20:1 or 40:1 objectives.