Soki, Rene and Rik: Thanks for your kind remarks!
@Rene and Rik : I get the point regarding the resolution query. So the formula does not need to be rewritten

Thanks for this interesting post, slime molds indeed invite to be explored more often.

Wow, beautiful phase contrast!

In case you want to do this without reflected light: You might try to cut a small piece out of the mask, mount it in e.g. euparal and observe it with a low power immersion lens, e.g. 10x/0.45 and try darkfield.

Excellent set, Charles. Wonderful & colorful details.

Good to hear that, Robert. Now what resolution did I achieve? The angular resolution formula is helpfull to assess what could be expected . (https://en.wikipedia.org/wiki/Angular_resolution) http://www.photomacrography.net/forum/userpix/5187_foto_1_6.jpg The partially open iris objective has an Na o...

Great set, fantastic colour and details.

I wonder what would other water organisms look like with same lighting method?

Well done, nice "portrait".
Thanks for sharing!

Regards,

Walter

Very interesting, nice section. Thanks for sharing.


Regards,

Walter

Very nice, Pau; all the tiny hairs are very detailed. And I like the black and white too.

Regards,

Walter

Thanks for sharing, Ken! Getting curious what it looks like at higher magnification.

regards,

Walter

... so your objective has a higher NA than the low NA of your dark field condenser? Exactly what objective is it if you don't mind? James, indeed the objective has a considerable higher Na than the condenser. The objective is, to be more precise, a100x magnification Leitz PL Fluotar oil immersion o...

Dear all, thanks again for the kind remarks! @James: The 100x objective has got an iris diaphragm which was partially closed. According the specs the Na with full open iris diaphragm is 1.32, closed 0.6. In this setup it is more open than closed. @Charles: Correct, a dry 0,8 Na darkfield condenser i...

You're welcome, Lou! The sensor of the camera is the CMOS type APS-C sized, which is "medium frame". The Periplan 6,3x 30mm eyepiece in this setup results in a large field number, FN28. The Objective is a 100x/ 1.32-0.6 iris immersion objective. Below 2 pictures of the setup including the led light....

Thanks all for the kind remarks. @Macro_Cosmos: Yes I was glad to have the opportunity to buy this slide from Klaus Kemp, who's been a master in diatom preparation for decades. And I don't know anybody else offering commercial type slides this good with this variety of types. @ Lou: The fiddling aro...