tickerguy wrote in post #16632239
I own a Canon 1.4x TC III and use it with some regularity behind the 70-200, which is why my 150-600mm is arriving on the brown truck today (confirmed out for delivery at this point.)
The 1.4x on the back of the 70-200 is just not enough far too often, even on the 7d with its crop factor. And while I can afford the Canon 400 prime now I lose autofocus (unless I tape pins) and with the TC I bet there's not much difference in IQ AND I lose some light-gathering over the Tamron. The gain is that I get IQ @ 400, but I spend more.
I'll probably sell the 1.4x TC once I use the Tamron a bit. If it obviates my desire to use it with the 70-200, the TC will go up for sale.
I owned a TC II and the III is materially
better in IQ. It's also more money, so there you have it.
Yea, that makes perfect sense to me - a 70-200 bare (as it has great IQ and AF for that range), and the Tamron for the longer work.
Bsmooth wrote in post #16632258
Also just throwing around some figures using the 1DMKII, which is a 1.3x factor sensor. With the 150-600 tamron, it essentially gives you a 780mm lens.
Now with a Canon 400 5.6 and 1.4 Ext you have essentially a 728mm lens.
I was just wondering which of these would be a better choice, granted with the 400 you lose a little bit of light and range, but I think that combo is still lighter than the 150-600. What do you think ?
Also are the newer 1.4 ext (version 2 and 3) any better than the 1st version ?, which i think I have.
Does the 1DMKII AF at f8? If not, then the 400 f/5.6 + TC would be a problem.
Without a TC, the 400 prime should AF faster than the Tamron, and for BIF the shutter speeds should be high enough that the lack of IS would be less of a problem. If you need more reach, or IS/VC, then the Tamron's probably the choice.
I don't know the version I of the Canon TCs. I wouldn't be surprised if the II was better, but I believe the III of the 1.4x isn't sufficiently better than you should overlook a good deal on a used 1.4x II.