I've been doing some very non-scientific comparisons with/without my 2x teleconverter. I'd assumed (wrongly) that my working distance with the TC on would be quite a bit less than with the straight 105mm. But it seems that it's just the opposite.
With the 105mm racked out all the way, the distance from the subject to the tip of the lens is about 5 1/2". With the 2xTC on, it's about 5 3/4". Does this seem right? And why? The teleconverter is not supposed to change the working distance of the lens but if you add the width of the converter, it should get shallower???
Rand
Working distance should stay the same. The lens itself is working in exactly the same way; the teleconverter is magnifying the lens's image on the way to the sensor. The extra length added to the system is also added to the overall focusing distance.
Thanks Craig. It just seems like I was a lot closer underwater with it on...maybe it's that 25% thing...
