TELE CONVERTERS

HI All,

Can I please have some help, I am thinking of getting a tele converter but which is the best to get & why??

Many thanks,

Andy

Andy,

I'm assuming you are talking teleconverters and not close-up filters ("diopters" -- hate that term, it's a unit, not a thing).

Teleconverters are the ultimate and purest of trade-offs. A 1.4x teleconverter will give you 1.4x the "zoom" at a cost of 1 stop and 1.4x drop in resolution. Likewise, a 2x teleconverter will give you a 2x zoom at the cost of 2 stops and 2.0x drop in resolution.

Universally, 1.4x TC's give better performance than 2.0x TC's. In fact, most people find that "digital enlargement" will do about as good a job as a 2.0x TC unless you are talking about SERIOUSLY good glass (e.g. the Canon 300/2.8 monster, which you would never take underwater anyways). A good 1.4x on a good lens will yield better results than the comparable "digital enlargement". From this point on, I'll just talk about 1.4x's.

I'm a Canon guy, so I'll talk Canon. I have found that the "cheap" Tamron and Kenko TC's aren't very good, but the corresponding "Pro" models are very good, and are darned near as good as the corresponding Canon versions at many times the price. Also, the Canon TCs are only usable on a subset of lenses because they contain an optical element that extends back into the lens a bit. The main reason to get the Canon TC is, if you are having focus problems or lack of sharpness with the TC, Canon will address it, but will ignore issues with a third-party TC.

So:

- If you can, you should use a better lens instead of a TC (not always possible)

- TCs always decrease image quality (how much depends on the lens and camera you are using)

- Stick with the "Pro" version of 3rd party filters, avoid the "cheapest of the cheap"

For underwater use, keep in mind that they are about 1" thick so you may need a different port.

Regards,

Dan

HI All,

Can I please have some help, I am thinking of getting a tele converter but which is the best to get & why??

 

Many thanks,

Andy

Depends a bit on which lens you want to use it with. I have no experience with the Nikon teleconverters since every time I touch a Nikon I somehow break it, but I think both the Kenko Pro and the Tamron Pro give excellent results (They might be exactly the same with different labels). As Dan said, higher magnification at one stop loss (depending on your focus light this may or may not be a very big deal). I agree to stay away from the 2.0 versions the 1.4 are much better optically. You might take a lens you like down to your local camera shop and shoot some still lifes and see how they look.

Bill

I would like to confirm the Kenko 1.4x people here use.

Its the Kenko Teleplus PRO 300 "DG" AF 1.4x Teleconverter. Is that correct?

Just curious since all websites I read about it state it is designed for lenses over 100mm and better if over 200mm. I am planning on trying it with a Tokina 10-17, as others have.

Just wanting to make certain I am looking the right TC.

that's the right converter for the 10-17

i pretty much agree with the above and find that converters seem pretty marginal on high resolution cameras like the 5D2 and have pretty much given up on 2x converter entirely. the Canon converters are marginally better than the Kenko on the Canon compatible lenses -- however there is still very substantial barrel distortion and the edges are VERY soft (may be a flatness of field problem)

the Kenko/10-17 combination is a unique underwater bastard that a number of people find useful