Radiolarians

Beatsy · Post by **Beatsy** » Sun Oct 02, 2016 12:26 pm

I've been taking a closer look at the radiolarians I used for the 4k video test stacks the other day. The sample vial is labelled "perhaps barbados" and my first scans revealed fossil species typical of the area. But I found others that I'm not so sure about since. For example...

First image is the more typical mix of types, second is one of the "stand outs" that doesn't appear to be associated with Barbados deposits. I'm very short on reference material for this area though, so it could be typical after all. More investigation needed...

Note: these are among the largest specimens as the smaller ones were separated out before making strews.

Edit: oops! messed up my maths. Scale bar is totally wrong. It's about 46µm in reality, not 100µm as shown.[/u]

JH · Post by JH » Sun Oct 02, 2016 1:50 pm

Regards Jörgen

Tom Jones · Post by **Tom Jones** » Sun Oct 02, 2016 8:00 pm

Absolutely gorgeous!

Tom

Lou Jost · Post by **Lou Jost** » Sun Oct 02, 2016 9:24 pm

Really beautiful light. They don't give the usual visual cues (like imperfect or flat lighting, or abrupt drop-off of background sharpness) that tell us we are looking at photos of microscopic objects. These could be photos of big pieces of glass jewelry or Tiffany lamps or big sea shells. That's hard to accomplish.

Beatsy · Post by **Beatsy** » Mon Oct 03, 2016 6:03 am

Thanks for the positive feedback everyone - always nice to get. And thanks Lou for the memory jog by mentioning "microscope". I've been meaning to try a brightfield approach by mounting on a coverslip and lighting from behind with an LED flat panel. In fact...

[short pause]

...just resumed typing after doing exactly that

Very quick stack at 50x as described above. Yowza! This is a way better result than I could get on my microscope as lens aberrations kick in once you get too deep into the stack (looking through a coverslip). FoV is 0.7mm wide here. Now they look much more like the illustrations and photos in the reference books. Definitely going to do more of these but I'll put them in a separate post. Thanks again for the prompt Lou!

Sumguy01 · Post by **Sumguy01** » Mon Oct 03, 2016 8:44 pm

Very nice photos.
Thanks for sharing.

benjamind2014 · Post by **benjamind2014** » Mon Nov 19, 2018 12:20 am

Wow, that has to be the best image I've seen of detailed radiolarians taken without a coverslip.

I presume these were taken with a 50x mitty?

anne · Post by **anne** » Mon Nov 19, 2018 12:42 am

Hi Steve,
thank you for showing this sample, I remember this.
Hope you will show more fo the species in this sample.

BR
Anne