MicrobeHunter.com Microscopy Forum

Hello I recently bought a zeiss 47 30 30 9904 polarized head attachment so I did not have to hold a filter up between the eyepiece and my eye anymore kinda hard to do when you have to manipulate the stage and other controls
well it has some controls that I am unaware of what they do I understand the small swing lever is for the linear polarizer swing arm but there's a Knob on the side that when I turn the images goes out

Well that is one way to place an analyser in a microscope, here is another:

Pol Monocular:

what does "auxiliary object mean"? and that head seems to have 2 slide openings were as mine has just one

what does "auxiliary object mean"?

Good question! I suspect it means that you can use it add a filter of your choice if you wish.

It would be good to get more feedback on this.

rs6000 wrote: ↑

Sat Sep 07, 2019 10:21 pm

what does "auxiliary object mean"? and that head seems to have 2 slide openings were as mine has just one

This might be a less perfect traslation from german language.
Here a retarder is meant that influences the rotation angle ofthe polarized light.
Here you can see such "Hilfsobjekte":https://www.mikroskopie-forum.de/index. ... ic=10998.0
Here you can read more on polarisation microscopy (in german, but lots of pictures):ftp://ftp.min.rub.de/pub/Medenbach/Mine ... tfaden.pdf

You only need real Pol components if you want to equip your microscope as a polarisation microscope = measuring instrument with added image forming.

If you are just looking for colourful images you insert a piece of plstic foil of CD-cover and observe the effect it has.
Glens first image shows where to put the polarizers in this case. If you use a bino tube and hold the analyser over the eyepiece it may not work at all or worse than in the shown position in the microscope head. Something happend in the bino head.

Bob

The advantage of placing an Analyser* (top polarized filter) in the head is that you can leave it there as it has very little effect on the illumination.

When you want to view something under polarized light you just need to place a polarized filter on the field housing.

This allows you to continue to use your usual binocular or trinocular head.

Note: This does not turn your microscope into a polarizing microscope, which is a specialist instrument, it just allows you to view specimens under polarized light.

* The Analyser can consist of a piece of polarized film, which may be more convenient to place in the head, it can be bought online.

Make sure it is linear rather than circular.

You can find the auxiliary objects on eBay. The lambda and lambda/4 filters. They can be used to tell the direction of the retardation in a polarizing material, along with the conoscopic viewing with the Bertrand lens in place. Using the Bertrand for conoscopic viewing is interesting and it involves determining colors in different quadrants of the image. Quite different than regular image viewing. It can be helpful in identifying chemicals with the polarizing microscope (This is getting to be a lost art).

Anyway, look for some lambda plates; they might be labelled glimmer, mica, quartz, rot, etc. The retardation that they provide can give some interesting visual effects, they can add color to an otherwise colorless sample, and add some contrast.

There is a photo on the cover of this months "The Anatomical Record" of some reptilian bone viewed under cross-polarized light with a lambda filter. This is just an example of what you can do with it (you can get on the covers of major biomedical journals). The article associated with the cover also has some nice polarized light bone images for those who are interested. I'll attach an image of the cover photo.

I'm also attaching a photo of some filter examples. The smaller metal style are older. The newer plastic versions meet the DIN standard, and are readily available. Just measure your slot to get the appropriate size.

75RR wrote: ↑

Sun Sep 08, 2019 10:08 am

Make sure it is linear rather than circular.

A circular polarizer is a linear polarizer with a retardation object on one side. So if it is used the right way round it can be used too. Some 3D-cinema glasses use circular polarizer foils of acceptable quality for microscopy purpose.

Bob

WOW you have a lot of sliders
I have never bought any but HAVE seen them around 400$ plus thats a lot of dough invested in those
my slot is 20.23mm BTW so the metal type are the proper ones I assume can you tell me the difference in all those silver one you have they look similar but writing on them is not the same

wstenberg wrote: ↑

Sun Sep 08, 2019 5:25 pm

The retardation that they provide can give some interesting visual effects, they can add color to an otherwise colorless sample, and add some contrast.

A full wave lambda plate can provide you with information about the molecular organisation of your sample. If the slow axis of the plate coincides with the direction of parallel bundles of macromolecules (for example cellulose in cell walls or polysaccharide chains in starch granules) then the wavelength that undergoes interference extinction shifts to higher values i.e. the reds (addition color) and the sample looks bluish. If the orientation of the axis is crossed with respect to the axis of the macromolecular bundles then you lower the wavelengths of extinction and you end up with yellow (subtraction color). This can tell whether in a microscopic body the fibers are oriented radially or tangentially.

Very nice collection of sliders btw. What does the one on the right do?