135L with TCs

[HDNitehawk]

Dave

I love the L primes, if your looking for a lens that does a specific job and does it better than any other it is the way to go. It sounds like what you are going for, you are wanting a lens that can do what it does very well. Of course Neuro is right you loose the versatility and his advice is good, the thing Neuro may have eluded to but didn't lay out specificaly and tell you is that once you use the 135L you are most likely not going to be happy with your 55-250. Once you see what the prime can and does produce you will find it hard to pick the 55-250mm up over the prime. The Canon L primes are fun to own, if you need that specific tool to use.

If you go with any of the L zooms mentioned, if you thought the 70-300mm L was heavy you will most likely think that about all the zooms in that range. As IQ upgrades go I think any of the mentioned lenses will give you that and would be a nice step up from where you are. If you want the one zoom that will come closest to creating what you can get out of the 135L I think you would need to go with the 70-200mm F2.8L II, lots of money but the best of the best when it comes to zooms and it heavy like a brick.

Good Luck

Edit: if you do go for a 135mm with a 1.4x or 2x TC, you don't need the new version III TC...get the old version II