Hi Jaako, My EF 28-135 IS USM and EF 100-400 IS USM make two sets of noises when power is first applied to the lens. I presume this is the result of the internal lens microprocessor resetting itself, and self-testing the image stabilizer mechanism and resetting the aperture blades.
Cheers Julian Loke * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
