In the case of more conventional office environments, the techniques in architectural acoustics discussed above may apply. Other solutions may involve researching the quietest models of office equipment, particularly printers and photocopy machines. Impact printers and other equipment were often fitted with "acoustic hoods", enclosures to reduce emitted noise. One source of annoying, if not loud, sound level emissions are lighting fixtures (notably older fluorescent globes). These fixtures can be retrofitted or analyzed to see whether over-illumination is present, a common office environment issue. If over-illumination is occurring, de-lamping or reduced light bank usage may apply. Photographers can quieten noisy still cameras on a film set using sound blimps.