Understand that I am nothing more than an amateur photographer so I come from a very simpleton point of view...and my tests are far from perfect, but I suspect most folks here fall into my category....

I did test the 1.4TC on 4 other lenses today...
The bigma 50-500...The auto focus really hunted...I suspect the only way the TC would work on this Lens is with a TriPod and lots of light...

The Sigma 135-400 did OK...While it did not hunt, the sample pics I took were rather soft...Here is a sample of some lemons shot from about 100 feet away at 400mm x the 1.4 TC = 560mm


I also ran some test shots on my 50mm F/1.4..It really worked well on this lens..Other than a longer focal point, I would not notice it was their...

Another lens, I tried it on was my DA*50-135 and again..Amazing results...Everything worked as if the TC converter was not there...Yes the HSM was in full effect..







Likely Tuesday when the 1.5 TC i ordered comes In, I will post more pictures of all the lenses involved...