Usability of a 100x-lens in photomacrography?

keks · Post by **keks** » Wed Feb 15, 2017 12:40 pm

I have just got a BD Plan 60 0.7 ELWD, but for some reason I can't remove the outer shroud, which shouldn't be a problem to my knowledge. I have even clamped the objective with 2 big cable glands, which allow me to put severe force to that thing.

Just for a test I have removed the shroud of my M Plan 5 without any problem.

I have read that the thread of the inner shroud has some glue in it that must be dissolved, could it be that the thread of the outer shroud has glue in it also?

keks · Post by **keks** » Thu Feb 16, 2017 12:26 pm

Ok my last post is outdated already, I managed to remove both shrouds. If there is interest I will describe my method in a thread related to that topic - if there is one. I guess nobody would find the information here.

rjlittlefield · Post by **rjlittlefield** » Thu Feb 16, 2017 12:37 pm

Perhaps this thread?

"Removing outer casing of Nikon BD objective", at http://www.photomacrography.net/forum/v ... hp?t=12127 .

--Rik

ChrisR · Post by **ChrisR** » Thu Feb 16, 2017 4:50 pm

@keks - it would still be good to know how you did it!

I would also like to know, if anyone has tried it, how to get the lighting parts off a BD APO. they are sprung, which changes the design. Nothing comes easily off mine!

keks · Post by **keks** » Sat Feb 18, 2017 2:25 pm

Ok I did describe the process in http://www.photomacrography.net/forum/v ... hp?t=12127

I have in between done some studies about optics because I want to assess which lens/sensor combination is good/bad, where the the limitations lie and what to change to improve the setup. I know how to calculate depth of field, effective aperture and cycle of confusion. Also I have calculated the size of the airy disc for objectives with a given f-number.

Now what puzzles me is 1. the calculation of the airy disc size for microscope objectives with a given NA, and 2. what must be the size of the airy disc to match the performance of the sensor (based on its CoC-size).

Somehow on all the pages I have checked the matter is described somewhat different, and some explanations seem to conflict. I am quite confused about that matter now.

Some short and simple explanation to 1. and 2. would be greatly appreciated, and also maybe a calculation example (Nikon M Plan 40 ELWD on a full frame Sensor, lambda 0.52 um, CoC 30 um). Thx in advance!