dhornick wrote in post #18102616
So I've read as many reviews as I can but I wanted as much feedback from here as possible.....I'm moving up from Crop to FF. One of the things I'm concerned about is losing the magnification from my crop sensor when using my 100-400 lens. But on the flip side I'm thinking about an 2X Extender.
I know about the loss of light, I know about having to double the shutter speed and I only use the 100-400 in daylight usually anyway so I don't see an issue with any of these issues.
Any other input????
So before you spend $2k on a camera and another couple hundred on a 2.0x TC, you might want to consider that your camera will not autofocus at F11 (F5.6 - > F8 -> F11 with 2.0x TC). If you're ok with Live View focus only, then it will work. Otherwise, the best you're going to do and keep autofocus is with a 1.4x TC (F8). You also lose considerable image quality using the 2.0x on the zoom.
Since this is for sports, where you want AF, the 2.0x TC is not going to work.
You might want to consider your real needs before you do all this just to end up with a solution that doesn't do what you're wanting as a goal.