I've owned the OM-D E-M5 and more recently the E-M1, but only recently have I begun to wonder if I need to change the focal length setting for the I.S. when I switch between lenses. Sorry, I have some time on my hands and trying to learn as much about my cameras as possible and this is a little detail I question if adjusting I.S. focal length per lens (or per zoom range) may result in better image stabilization for each particular lens? Forgive my ignorance in advance if I have missed some sort of "common sense" logic or knowledge about the I.S. in Olympus cameras. If I recall the instruction manual correctly, it says you should set the actual focal length (not the 35mm/FF equivalent) of any lens which is NOT MFT or FT... say an old OM manual lens and Voigtlander, etc. I just wanted to be sure it wasn't necessary, if not simply better, to set the focal length for the I.S. when switching between lenses? 2 examples: Ex. 1) I have the 75mm f1.8 and the I.S. shows focal length at 12mm. Should it not be set (if not automatically detected by the camera) to 75mm? Wouldn't it make sense to match the actual focal length of the lens currently being used. I mean 12mm vs 75mm is quite a big difference. Ex. 2) I have the 12-40mm f2.8 and when I check the I.S., it seems set to 12mm. When I zoom out to 40mm, I check the I.S. again and it still shows 12mm. Should it not match the 40mm focal length (or whatever in-between)? You shouldn't have to reset the I.S. focal length manually, however, it doesn't show any change to I.S. focal length. Maybe I'm over thinking this and perhaps the camera actually does adjust and account for the actual focal length for I.S. optimization IN CAMERA.. doesn't necessarily show it when you check the I.S. settings? Or it doesn't and you just either have to live with a default I.S. focal length or go through the trouble of adjusting per lens. FYI, I have tried adjusting the focal lengths to see if there's any difference.. to be honest, it seems to work just as well regardless of focal length settings to the I.S. Perhaps I've just answered my own question just now, but ...If anybody has any insight into this, it would be appreciated so I have a better bit of solid knowledge wrapped around this particular subject and understand what happens inside my E-M1 regarding I.S. and focal length setting when MFT & FT lenses are used.