Finally got my hands on a new Mk111 to try yesterday thanks to a fellow BF'er.
We conducted a few tests taking pictures of a static object, all at the same focal length, same ISO, same white balance, same matrix metering, same 21 point dynamic focus points, all shots were tripod mounted, the same distance from the subject. All shots were left untouched, no further processing than that set within the camera.
Both the 300mm f2.8Vr and the 500mm f4Vr were used with a D300s and all three current model TC's.
The only variance from picture to picture was the shutter speed, to try and get the same exposure for each shot. There was also the slight possibility of variable camera shake as a remote wasn't used.
Obviously the initial image differs from shot to shot but what was really surprising was that when you crop the image so that the subject matter was the same size for each picture no matter which TC was used it soon becomes apparent was the difference when shown on the web is marginal.
In other words, the image taken with the 500mm plus 2.0TC was very similar to the one taken without a TC but cropped by 66% on NX2.
What this tells me is that, for the internet, it makes little difference using a TC !
The one thing relating to the image however is that when you crop it, it becomes smaller so for printing purposes it might matter.
In terms of using the TC's AF was quicker on a naked lens, then the 1.4 but strangely the 2.0 was a bit quicker than the 1.7.
AF was possible with the 2.0TC but was very slow for non contrasting subjects and would prove very problematic for BIF .
My tests must be flawed somewhere as what it seems to say is that a TC is a waste of time, just crop. Maybe someone can enlighten me.
I could show a series of photo's but as the difference isn't apparent there is little point. If you have a TC try it yourself and see what you find.
cheers Dave
