Leica DM IRB manual Parfocality, Dry objectives, Oil immersion objectives, Exiting the Learn mode

Parfocality

Select the “Parfocality” option (“PARF”) in the Learn mode by pressing the “CHANGE” key; the “PARF” option now flashes.

Confirm your choice with the “LEARN” key.

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ADJUST & LEARN

Learn mode: Parfocality

Dry objectives

Select the dry objective with the highest magni- fication by pressing the objective nosepiece keys (behind the focus handwheel on the left).

Focus the specimen with the focus handwheel. Use the “STEP” key to select the suitable focus stepwidth, also using the focus keys if neces- sary (behind the handwheel on the right). When the focus position is set, the z drive stops near the focal plane.

Confirm the learned focus position by pressing the “LEARN” key. “ADJUSTED” appears in the display.

Now select the dry objective with the next lower magnification.

Focus the specimen again with the focus hand- wheel and confirm with “LEARN”.

Repeat this procedure until you have reached the smallest dry objective.

For low-power dry objectives (5x, 10x) it is ad- visable not to correct the focus any further, as these objectives are focused immediately after switching on.

Oil immersion objectives

Once the parfocality has been learnt for all the dry objectives it can be done for the immersion objectives.

Please remember that if the specimen is very small and lightweight it must be fixed onto the stage to prevent it being moved by the adhesive force of the oil.

Select the oil immersion objective with the objective changing key.

Apply a drop of immersion oil to this objective. To do this, you can move the objective to the most easily accessed outer position with one of the objective changing keys.

Return the objective to the working position and focus.

Confirm the learnt focus position by pressing the “LEARN” key. “ADJUSTED” appears in the dis- play.

Proceed similarly for any other immersion ob- jectives.

Conclude the parfocality setting by selecting the “EXIT” option with the “CHANGE” key and confirming with “LEARN”.

Exiting the Learn mode

To leave the Learn mode, select “EXIT” and confirm with “LEARN”.

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