odonnellake wrote:
I am strictly a hobbyist and am looking for an affordable way to increase my capabilities. I mostly shoot wildlife, landscape, and macro. I would love to be able to get closer in on the wildlife and any enhancement I can do in macro intrigues me. Not sure what would happen with the wide angle. I shoot with a common 60D and the following lenses: 70-200 Cannon zoom (1:2.8), Tamron 10-24 (1:3.5-4.5) wide angle, Cannon 100 (1:2.8) Macro, and a couple of cheap Cannon kit lenses 75-300 zoom and 18-55 EFS (that I rarely use). I’m told I could use the teleconverter with both my zoom and my macro lens and that it should definitely be a cannon. I’m wondering what I give up here. Is there distortion or loss of clarity? Can someone with experience help me sort through this? Thanks!
I am strictly a hobbyist and am looking for an aff... (
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You would be able to use a 2X teleconverter on your f/2.8 lenses... The 70-200mm would "become" a 140-400mm f/5.6 and the 100mm macro would "become" a 200mm f/5.6.
Your 60D is able to autofocus an "f/5.6" combo such as these... but not any less (newer models such as 80D and 7D II can autofocus a combo a stop slower.... f/8.... with some limitations).
Likely the "dimmer view" will cause AF to slow down and hunt more in situations with less light and/or lower contrast.
Image quality will "take a hit". But it depends upon which 70-200mm f/2.8 you have. If it's the current Canon EF 70-200mm f/2.8L IS USM "II", that works pretty well with the Canon EF 2X "III" teleconverter. Some people find the image quality acceptable for their purposes.
I have the earlier versions of both lens and teleconverter... and will not use them together because image quality takes too big a hit. I have occasionally used the weaker 1.4X II teleconverter, though and the result are "okay". Not great, but usable for modest purposes. I have three 300mm and a 100-400mm lens, so don't really need to use the 70-200 + 1.4X... but you might consider that as an alternative, since 1.4X teleconverters do a lot less "damage" to images. I have never tried using either teleconverter on my Canon 100mm macro lens.... that really serves no purpose since I have several lenses that give me 200mm focal length (as do you).
Canon's own teleconverters are very high quality... but they all use a protruding front element that needs to fit insider the rear barrel of any lens they are used upon. This prevents them from being used on some lenses that either aren't large enough diameter and/or have rear elements that move during focusing and would interfere with the teleconverter. For example, you could not even fit the Canon teleconverters to your 75-300mm (I assume it's the "III" without IS or USM that's often sold in kit with cameras... and isn't a particularly great lens to begin with, so would likely be awful with any teleconverter magnifying it's short-comings).
Most teleconverters cannot even be fitted to Canon EF-S lenses.... Not that many of them would be good candidates to use with one, anyway.
There are teleconverters from Sigma, Tamron and Kenko, too. Those are a lot less expensive than Canon's and may be usable. But it's a bit of a gamble, if one of those 3rd party TCs would give you usable images. I know the Kenko 1.4X "MC4" is sharp in the center on most lenses and can be a good choice for use an APS-C crop camera like your 60D, in particular. The slightly more expensive Kenko 1.4X "Pro 300" has better corner sharpness, so might be a better choice for full frame cameras. (Though, to be honest, some softness in image corners often is no problem with using telephotos.)
I don't know anything about Kenko's 2X in either of those series.... I haven't used them. And Kenko has a new "HD" series with both 1.4X and 2X, which I haven't used and can't compare. More expensive, the "HD" are the only TCs I'm aware of that can mount an EF-S lens (still, I'm not sure why, with the current EF-S lenses... but some future EF-S lens may benefit). I notice that the Kenko HD teleconverters use fewer elements than either or the other series. I also have no experience with Sigma or Tamron TCs.
In the end, you almost have to give it a try and decide for yourself if any particular lens/TC combo will serve your purposes adequately. In general, TCs work best on extremely high performance lenses, which produces such excellent image quality they can tolerate a bit of loss.... lenses like Canon's 300mm f/2.8L, 400mm f/2.8L, 500mm f/4L, etc. They also usually work best with prime lenses, as opposed to zooms. But you'll never know if some combo might work for you, unless you try it for yourself.