Final Considerations - Picture Taking with the Zeiss Photoscope 

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Use High Light Intensity to Focus!!!!!

1] Use the Phonographic Reticule to achieve Kohler Illumination with the 10X Objective & an Optivar setting of 1.25

2] Expand the Field Diaphragm just beyond the Field of View.

3] Check to be sure that the built-in Blue Filter (Rt.-hand Base of the Scope) is inserted and that the light coming through the Field Diaphragm looks Blue.

This filter must never be removed from the light path!!!

4] Insert the CLEAR Blue Filter over the Field Diaphragm for UNSTAINED & Phloroglucinol-Stained material.

Remove the Clear Blue Filter for Toluidine Blue-Stained Material.

5] Place a Polarizer over the Field Diaphragm & Rotate it to achieve MAXIMAL Illumination (MINIMAL POLARIZATION). I call this 0-Pol (0P). It enhances contrast with unstained material and specimens stained with Phloroglucinol.

6] Set the Film Sensitivity Dial to DIN 27. (for ASA 100 Film)

Reduce Illumination so that the needle is near the Blue Line on the light level indicator on the light meter face.

Press A! You should hear the shutter open & close plus the motor which transports the film.

The exposure should be one second or longer!

7] Rotate the Polarizer to achieve MINIMAL Illumination
                                   (Full Polarization or FP).

8] Open the Field Diaphragm completely.

9] Turn the illumination to MAXIMUM.

10] Take photos at DIN 30, 33 & 36.

1] Flip out the High Mag Condenser Lens.

2] Remove the Clear Blue Filter from the well over the Field Diaphragm.

3] Place the Frosted Blue Filter over the Field Diaphragm. It may not fit exactly (this is OK). The light is uneven at low magnification. This produces a bad photo. The frosted filter diffuses the light and eliminates most of the problem.

Be careful to see that the frosted filter is not in focus by moving the condenser up and down. You may need to defocus the condenser to achieve this. If you don't do this, your pictures will be frosty!!!!!

4] Set the Light Level to 8

5] Set the DIN to 27

6] Expose the Film (Press A)

Take Pictures with Full Polarization at DIN 30, 33 & 36

O-Pol will not be helpful at low magnifications.

If the specimen is heavily stained with Toluidine Blue,

Remove the Frosted Blue Filter and spread a sheet of Fine Lens Paper over the Field Diaphragm.

Expose the film as you would above at DIN 27. The lens paper does what the frosted blue filter does but it does not add any color!!!!! It would be nice to have a neutral frosted filter.