If image appears blurry at 40x after focusing at 10x, most likely cause is:

Practice question

Question

If image appears blurry at 40x after focusing at 10x, most likely cause is:

Options

Choose one · Correct answer highlighted

Incorrect use of coarse adjustment at high power causing slight defocus; use fine adjustment and check coverslip thickness Correct Iris fully open Stage clips missing Base unstable

Explanation

Parfocality should maintain focus, but slight refocus with fine knob needed. Also check oil, dirty lens, wrong coverslip (#1.5 required).

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