I am not sure I know where this thread is going. No one is more convinced of the efficacy of, or is more enthusiastic about IS technology than myself. However, after several attempts, I came to the conclusion it just does not really do much for a lens/camera in rapid motion, as in panning in either mode 2 or mode 1. When IS is engaged and I am trying to follow a moving object, I find the image seems to lag behind the motion, making it very hard to follow it. The object seems to then ""lurch" forward in the viewfinder as it attempts to catch up. In one attempt the lens began a "screeching" sound and I quickly turned it off! All very disconcerting and, I repeat, "worse than useless" for me personally in this particular application. I only have experience with the EF300/2.8L IS in this respect. While I also have the EF600/4L IS, I have not done any panning with it and, rather obviously, do not hand hold it when shooting. I still think the question raised earlier needs to be answered. Why have a switch at all if the lens operates as suggested? Still makes no sense.
My understanding is that the IS works in two directions at 90 degrees . . . usually perpendicular and parallel to the horizon. In normal "landscape mode" panning, mode 2 would be engaged. The lens would stabilize in the direction perpendicular to the direction of panning with no effect in the other direction. It seems obvious that IS can not possibly be effective in the direction of panning. Trouble is, in my application, I am always panning at an oblique angle. I don't see how IS can be of help here. And my personal experience has borne this out. Perhaps a simple panning operation, with a well behaved object, like a sports car, mode 2 might be effective. I have not had such cooperative subjects > From: Gerry Morgan <[EMAIL PROTECTED]> > > Terry Danks wrote: > >>The image becomes jumpy as IS attempts to do what is an impossible job > >>for it. IS may or may not work in mode 2 for panning an object moving in > >>a well defined horizontal plane, such as a sports car. For a bird > >>approaching overhead at an oblique angle it is not useful. > > The first 100-400 IS lens that I owned behaved in a manner similar to that > which Terry describes. Intermittently, the image would jump around in the > viewfinder. Unlike Terry, I found that it happened even when I was not > panning. [snip] Terry, have you observed this jumpiness with more that > one IS lens? -- Terry Danks Wildlife & Nature Photography http://www3.ns.sympatico.ca/danksta/home.htm * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
