Photo Microscopy

Excellent:  microscope introduction, resources and advice;
  my microscope optics fundamentals
Rolf Vossen Experiments and tests:
  objectives, eyepieces, condensers, illumination
Camera + Microscope Combinations
Macro links  
Focus stacking
Polarizing filters e.g. for DIC or attenuating specular reflections
Practical guide to binocular collimation - Ron Green 2008

Photo 2:  Nikon Trinocular Head …Type Siedentopf

Adjust left eyepiece tube.
Comments. With this type of head the right eyepiece is rotated by a metal band under a fibre cover, so try to avoid working on the right or you may also have to adjust the said band as well.
Note the two-collimation screws may be very tight and sealed with a drop of epoxy resin,
so it is most important a good fitting screwdriver is used;
as you may have to give it a short sharp rap to break the seal on each of the screws
(not with a 7 lb hammer please).
Difficulty level… Easy, but the above screws can make one’s heart rate increase.

Nikon
  Labophot   LED conversion (also for Optiphot 66)   Fine focus repair
  Metaphot
  Optiphot
    Optiphot 2
  Optiphot 66
    Optiphot 66 DIC
  Optiphot Infinity
    Optiphot 100 DIC

  210mm Industrial CF objectives
  Condensers
  Confocal microscopy - McMaster
  DIC
  Optem Optizoom 0.8x-2x
  Phase contrast   ELWD turret, condenser
  Sliders
  Stages and crossed roller bearing rails
  Trinocular heads
  Vertical Illuminators

Microscope Stylus Images

Background

Photomicrography and macro photography are both InterWeb subjects
popular among better writers than I.
Consequently, content here will focus (heh) on specific experiences,
rather than more general theory and technique, which for macro photography see e.g. Allan Walls.

Years ago, I saw and admired Micrographia and more recently Ray Parkhurst's work
including at vinylengine.com Stylus images on the not cheap (but not massively expensive).
Phonograph needle image capture combines 3 of my long-time interests:
audio, photography, and microscopy.

While not aspiring to artistic images,
capturing clear and useful phono stylus image wear images seems achievable.
Ray demonstrated that Nikon's long working distance CF objectives are well-suited to this,
but my American Optical (AO) microscopes lack long working distance objectives.

Generalities

Microscopes traditionally shared some mechanical conventions:

• RMS (Royal Microscope Society) Objective threads
• 23.2 o.d. eyepiece (ocular) tubes
• 160mm "tube length"

Consequently, optically-matched objectives and oculars could be swapped among frames.
Practically, after frames evolved from straight tubes to separate heads with prisms,
additional lenses might be introduced, specifically to allow for e.g. vertical illuminators
and/or polarizing filters to be inserted into optical paths.
These optics are typically optimized for some manufacturer's objectives optical formula.
Most modern microscopes use other than RMS threads; here is a list.
Here is a list of threads used in astronomy.

AO Series 10 - headless

Disappointed with EPIStar images, Series 10 configuration experiments resumed.

RGB ring light

Microscopes better resolve using blue illumination,
since shorter wavelength and less opportunity for chromatic aberrations.
A 40mm RGB LED halo ring fits around microscope objectives
and can be supported by a 20mm i.d. o-ring.

O-ring below LED halo blocks illumination...	Bayer-filtered camera sensors have relatively sparse blue pixels, aliasing is liable with less than 4x oversampling. Dark wedge along the center of the above M55E stylus image is partly surface not in focus, but also stylus angle not 45 degrees (twisted cantilever).
Curled strip of business card glued to the halo backside... ...an o-ring secures LEDs to the objective:	Rotating the headshell in a clothespin brings more of the stylus upper surface nearly in focus: green light employs more camera pixels

Improve contrast by putting something flat black between the cantilever and its light plastic grip.

MEIJI S.PLAN M 20X longitudinal chromatic aberration correction

Microscope fine focus is indexed in microns, 200 per revolution.
Images of 0.01mm test slide (with cover slip) using MEIJI S.PLAN M 20X with Series 10 tube lens
and Olympus PE 2.5X; no matching corrections.
Numbers by colors are micon settings to focus that color:

red 144	green 153
white 148	blue 153

Red focus is out about 9 microns from blue and green..
This is axial (or longitudinal) chromatic aberration.

A.O. 10X with NFK 3.3X

With an AO head, AO objectives are substantially corrected, better matching a Nikon CF PL relay lens.
Headless, an NFK relay lens approximates AO tube lens corrections.
Finding a stylus in microscope objectives is easier using conventional oculars
than with camera Live View.
Since this AO head has an infinity tube lens, infinity objectives are wanted.
Series 10 AO Spencers often include a 10X objective;  how well does one work on a stylus?
Because they are smaller in diameter than MEIJI and Leitz objectives
for which cardstock half-cylinders were epoxied to LED halos, a shim was cut from clear vinyl tubing.

This AO 10x objective has about 4mm working distance.
With halo illumination, a stylus tip is better illuminated with cartridge vertical centerline
rotated more nearly 60 than 45 degrees from horizontal, reducing surface in focus.

With NFK 3.3X relay lens and about 200mm projection distance,
full field of view with APS-C sensor is usefully in focus;
both of these images (downsampled, but not cropped)
were captured after central focusing (zoomed Live View):
 

After visually confirming that minimal detail is lost by downsampling original (5472x3648) images by 3x,
then, given optics are NOT matched for color correction,
compared whether blue (left) or green (right) illumination yields more detail:
 
Approximate IrfanView color corrections settings for recovering dynamic range after grayscale conversion
and before 3x downsampling: brightness ~25, contrast ~99, gamma ~1.65