This is description of this part:
Carl Zeiss Jena Planachromat 25x microscope objective with M19 thread, for infinity systems, for work without a cover glass.
Basic parameters:
Manufacturer: Carl Zeiss Jena
Engraving on the objective: Planachromat 25x/0,50 ∞/0
Magnification: 25x
Numerical aperture N.A.: 0,50
Free working distance: 3,1 mm
Tube length: infinity (more precisely: 250 mm)
Optical correction: planachromatic
Cover glass: no - this objective is intended for work without a cover glass
Immersion: no - this is a so-called dry objective
Phase contrast: no - this objective has no phase ring inside
Polarisation: no - this is not a polarising objective
Thread: M19
Plan compensating eyepieces: yes, required - this objective calls for eyepieces with additional correction (designated "PK" by Carl Zeiss Jena)
Direct projection and macro photography: no - this objective does not work in direct projection mode and is not suitable for macro photography by connecting the objective directly to a camera
This objective can be used as:
- an objective for work in reflected light (EPI), for biological as well as, among others, metallurgical or mineralogical applications
- an objective for work in transmitted light, among others with biological specimens or, for example, with mineralogical thin sections
A few facts about Carl Zeiss Jena objectives with M19 thread (CZJ M19) and their compatibility with various microscopes of this company:
- these objectives serve mostly technical applications and are intended for work without a cover glass (marking ∞/0)
- CZJ M19 objectives intended for biological applications (that is, marked ∞/0,17) are most often used on Carl Zeiss Jena NU / NU2 microscopes
- in Carl Zeiss Jena Nf and Lumipan microscopes, CZJ M19 objectives are used together with the EPI illuminator and can then work both in bright field and in dark field
- in Carl Zeiss Jena Polmi-A microscopes, CZJ M19 objectives can be used, but they give a magnification other than the nominal one
- Carl Zeiss Jena Amplival / Amplival Pol / Amplival Interphako / Peraval microscopes have an interchangeable nosepiece, and there is also a nosepiece intended for these microscopes that accepts objectives with M19 thread
- Carl Zeiss Jena Metaval microscopes use newer versions of CZJ M19 objectives (those with a coarsely knurled rim and a glossy barrel), yet many people experiment with older M19 objectives on these microscopes
- Carl Zeiss Jena Epignost and BK 70x50 microscopes were produced in various configurations - and some work with CZJ M19 objectives
- Carl Zeiss Jena Vertival / Epival / Nf / BK 70x50 microscopes often allow work with CZJ M19 objectives in EPI dark field mode
- on inverted metallographic Carl Zeiss Jena Epityp-2 / Neophot-21 microscopes, many people use biological objectives intended for work with a cover glass alongside metallurgical ones, and place the slide with the specimen on the stage "upside down", that is, with the cover glass facing downwards
What is this part needed for?
- if you need an objective with this magnification for one of the microscopes with which it is compatible (additional information can be found in the description)