Chest films acquired in the lateral decubitus position (with the patient lying on their side) are more sensitive, and can detect as little as 50 ml of fluid. At least 200ml-300 ml of fluid must be present before upright chest films can detect signs of<unk>  effusion (e.g. blunted costophrenic angles).
Pleural effusion chest x ray
Bronchitis chest x ray
Pleural effusion physical examination
Air embolism chest x ray
Pneumothorax chest x ray
Pulmonary edema chest x ray
Aspiration pneumonia physical examination
Pulmonary nodule chest x ray