Crosed eye stereo Queen of Spain fritillary (Issoria lathoni

JH · Post by JH » Tue Dec 03, 2019 6:52 am

Was testing to find the best compensating variation settings for using the Nikon plan apo 20x NA 0.75 0.17 160mm objective. The result seems to be best at approximately 4 cm extra tube. First some heavily cropped pictures of some dust.

Proof of concept a crossed eye picture of a Queen of Spain fritillary (Issoria lathonia), Storfläckig pärlemorfjäril. (Not as flat as one could have thought)

Best regards
Jörgen Hellberg

Lou Jost · Post by **Lou Jost** » Tue Dec 03, 2019 7:19 am

That's something I've been wondering also for a long time. Nice to see a test. Did this correction for lack of coverslip still leave the final inage degraded compared to using the objective with a cover slip?

What if you just added a coverslip to the front of the objective? You can easily cut coverslips to any shape using a cheap glass scoring tool.

Pau · Post by **Pau** » Tue Dec 03, 2019 8:06 am

Very interesting, Jörgen.

One important clarification, please: Is your 20/0.75 the OEM no name golden version or the typical microscope one with Nikon and 0.17 written on its shell?
(there has been some discussion on the different cover correction of both versions, https://www.photomacrography.net/forum/ ... p?p=243057 )

I would really appreciate a full size version of your scales stack or a 100% crop of it.
The 0.17 version I have easily outresolves my 18Mpx sensor when used as intended.
https://www.photomacrography.net/forum/ ... 770#245770

Lou Jost · Post by **Lou Jost** » Tue Dec 03, 2019 9:09 am

Pau, as you know, both the objectives you mention are infinity-corrected, but JH mentioned a 160mm tube length for his. Maybe he has an earlier finite version?

Pau · Post by **Pau** » Tue Dec 03, 2019 9:25 am

Lou Jost wrote:Pau, as you know, both the objectives you mention are infinity-corrected, but JH mentioned a 160mm tube length for his. Maybe he has an earlier finite version?

Ops! I need to read more carefully

Thanks for pointing it.
This makes more sense.

JH · Post by JH » Tue Dec 03, 2019 11:08 am

Hi Pau and Lou Jost - thanks for the questions

This is the 20x plan apo NA 0.75 objective. WD with coveslip is 0.64 mm.

Here is a corner and a mid picture at 100%. This was direct projection on a FF sensor. I have done some WB, deleted noise and dust, and done some sharpening.

Best regards Jörgen Hellberg

Corner

Mid

Pau · Post by **Pau** » Tue Dec 03, 2019 11:23 am

Thanks, Jörgen!