How much time should be spent in the darkroom before testing for fog?

Spending 15-20 minutes in the darkroom before testing for fog is the appropriate duration because it allows sufficient time for the film or imaging plates to acclimate to the dark environment. This period is critical to ensure that any potential fogging caused by light exposure or environmental factors can be accurately evaluated.

During this time, the ambient light levels can stabilize, and any residual light from the loading processes can diminish. Testing too early might lead to the misinterpretation of fog levels, as the film may not have had adequate time to adapt to complete darkness, possibly resulting in false readings. Ensuring proper acclimation is essential for obtaining reliable results regarding the presence of fog, which can affect the quality of radiographs and the overall effectiveness of radiographic inspections.