Purslane (Portulaca oleracea) seeds

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nic
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Location: Cervia (RA) - Italy

Re: Purslane (Portulaca oleracea) seeds

Post by nic »

Could it be very diffuse light allowing the interference to show through a thin top layer? I get the same thing with black beetles. If you diffuse the light enough (a lot - beyond ridiculous) then sub-surface patterns and colours start showing clearly instead of the outer surface. Doesn't look anything like the black beetle does to the eye when this happen - even with a loupe.
the same colors can also be seen with the stereomicroscope .. if anyone wants to receive some seeds, please tell me the mailing address and I will send them by post
Last edited by nic on Sat Apr 03, 2021 10:27 am, edited 1 time in total.
nicola merloni

nic
Posts: 60
Joined: Tue Dec 26, 2017 6:29 am
Location: Cervia (RA) - Italy

Re: Purslane (Portulaca oleracea) seeds

Post by nic »

Guppy wrote:
Sat Apr 03, 2021 5:59 am
Hi Nic

Very nice pictures, I like them very much!
Did you use LED for lighting?

Kurt
Yes, I used 4 led spotlights of 3.8w each, and also I put a white diffuser ring around the seeds ..
nicola merloni

Guppy
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Re: Purslane (Portulaca oleracea) seeds

Post by Guppy »

Hi Nic

It would be interesting to see if the colors can be seen with flash.

Kurt

Pau
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Re: Purslane (Portulaca oleracea) seeds

Post by Pau »

Are these seeds natural or bought from a commercial source?
In the second case one possible explanation of the interference colors could be a chemical treatment deposited in fine layers

I don't think that the colors could be due to excessive light diffusion, in fact the opposite seems more likely to happen

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Pau

nic
Posts: 60
Joined: Tue Dec 26, 2017 6:29 am
Location: Cervia (RA) - Italy

Re: Purslane (Portulaca oleracea) seeds

Post by nic »

Pau wrote:
Sun Apr 04, 2021 10:18 am
Are these seeds natural or bought from a commercial source?
In the second case one possible explanation of the interference colors could be a chemical treatment deposited in fine layers

I don't think that the colors could be due to excessive light diffusion, in fact the opposite seems more likely to happen

Note: PM sent
these seeds were collected in the field .. derived from spontaneous plants
nicola merloni

Pau
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Re: Purslane (Portulaca oleracea) seeds

Post by Pau »

Nicola, thank you so much for posting it and for the seeds :D

I've posted some pictures here https://www.photomacrography.net/forum/ ... 23#p273323
Pau

nic
Posts: 60
Joined: Tue Dec 26, 2017 6:29 am
Location: Cervia (RA) - Italy

Re: Purslane (Portulaca oleracea) seeds

Post by nic »

rjlittlefield wrote:
Beatsy wrote:Could it be very diffuse light allowing the interference to show through a thin top layer? I get the same thing with black beetles. If you diffuse the light enough (a lot - beyond ridiculous) then sub-surface patterns and colours start showing clearly instead of the outer surface. Doesn't look anything like the black beetle does to the eye when this happen - even with a loupe.
Interesting! In general I'm used to seeing strange stuff when I look closer, sometimes with very strange colors (e.g., HERE). But I've photographed a lot of black beetles, and with those I don't remember seeing any effect that I can match with your description. If you have a specimen handy, it would be an interesting study to see the beetle shot both ways.

In any case, I'm inclined to think that's not the difference with nic's seeds, because of the photos shown at the links I provided. Those photos are high mag, apparently similar to nic's, but with no trace of the trippy colors. I checked to see if they had been converted to grayscale, but apparently not that because in the histograms there are clearly separated RGB profiles.

--Rik
it is also possible that I was wrong in attributing these seeds to the Portulaca oleracea species; I often collect seeds - one of my favorite subjects - but sometimes I do it quickly, and without noticing precisely the species and the place of collection. In this case I found the seeds with only a few dry capsules in a box, perhaps a long time after harvest, and it is possible that the attribution of these seeds to P. oleracea is incorrect. I'll come back to collect the 'oleracea' seeds and then I'll let you know ..
nicola merloni

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