What is the recommended starting objective when focusing a microscope?

The recommended starting objective when focusing a microscope is the low power objective. This option is ideal because it provides a wider field of view and a greater depth of focus, making it easier to locate the specimen being examined. Using the low power objective allows the user to scan a larger area, ensuring that the specimen is centered and allowing better initial alignment and focus.

Once the specimen is in clear view at low power, the user can then switch to higher power objectives for more detailed observation. Starting with a coarse objective or high power objective may result in difficulty in finding the specimen or risk damaging the slides or the microscope optics. The oil immersion objective is specifically used for enhanced resolution when observing very fine details but is not appropriate for initial focusing, as it requires specific techniques and additional steps.