Jon wrote in post #17952541
Piece of glass? If pieces of glass in the image path bother you, then mount an empty tube on your camera. Canon designs a lens group specifically to compensate for physical motion while complementing the other lens elements. That's been the case since they offered the first IS lens in 1995. Go look at their lens diagrams and descriptions.
Already done, quite a while ago. Please re-visit those descriptions as it is just a piece of glass that is moved around and uses refraction to compensate for vibration. The other pieces of glass (and Fluorite), namely lenses, are more than welcome to be in the optical path in my lenses. Incidentally how does a flat piece of glass complement other elements?
Not having a dig here but, with one exception, I have invariably found that I get more "Keepers" with the IS turned off - so what is the point of an extra flat piece of glass in the optical path? Even at 800mm hand held IS gives me no noticeable advantage, yes I can get lower shutter speeds but if the light is that bad then I won't get a decent shot anyway. More importantly IS interferes with AF. It slows acquisition and interferes with tracking moving subjects - try it for yourself. If you cannot see the difference then you are either using a lens that I have not encountered or a Canon camera that I have not tried - possible but not likely. Again don't take my word for it - try for yourself. I notice that your gear list includes a Canon 300 F4 L IS, nice lens, but try tracking birds with that and the IS on! I also noticed the 300 F2.8 L IS - better but still a problem. I mention these because I did/do own them as well as several others in your list. It's a pity you don't live closer as I could demonstrate what I am getting at in minutes/seconds.
Please feel free to criticize my observations/opinions - I will not take it personally as I am getting a higher success rate (as are quite a number of local Togs who have turned IS off) so I and they are quite happy! I am just trying to help others do the same - try or ignore, it's up to you.
The exception that I mentioned above is my (recently acquired) Canon 100-400 Mk2 which I am having problems holding steady. I have no idea why as I have no problem with other lenses regardless of focal length or weight - well maybe not a 1200 F5.6! As a result I am trying IS mode 3, I have tried modes 1 and 2 and whilst better than older lenses they exhibit the same problems, mode 3 is looking promising though.
Sorry about the long post but just trying to share simple, free, improvements that can help (and have helped) others. Isn't that what these forums are for? I have certainly learned a lot to my advantage here.
Life is for living, cameras are to capture it (one day I will learn how!).