When using the 100x magnification and oil immersion, what is it important not to do?

Question

When using the 100x magnification and oil immersion, what is it important not to do?

A. Use the fine adjustment knob

B. Use the coarse adjustment knob

C. look through the ocular lens(es)

D. move the stage horizontally

Answer 1

Hi Louis Alain P.,

Seeing as how you already adjusted the coarse focus before switching to oil-immersion, why would you risk running the lens into your specimen and damaging one or the other, by using coarse focus again?

If you remembered which way was up, then you could withdraw the lens using coarse focus. But then you couldn't safely bring it back; you'd have to switch to lower objective lens power and focus that, then switch in the 100x lens.

--Cheers, --Mr. d.