Which extender is best

[muldereric]

Hi all,

When I am fotographing, I sometimes need a focal lenght beyond the focal length of the lenses that I own.
Because the lenses nowadays are not getting much cheaper, buying for example a 400mm lens is not funny!
Therefor, as I am usually shooting during daytime in well lit environments, I would like to buy a zoom extender (TC). That way, I can keep using the lenses I already own without having to buy new ones for those rare occassions where I need them.

It so happens that both Canon, Sigma and Kenko sell teleconverters, but I find it hard to pick one.
Therefor my question "Which one would you pick and why?".
Shooting all kinds of subjects, so no particular purpose for the TC other then "just extending" .
I am curious about the results!

 

[Vikmnilu]

Hello!

TC's are nice to get an extra reach (40% more on the 1.4x and 100% more on the 2x) in those cases where you need to "be closer" to your subject.
I bought a 1.4Canon TC II in June just before my excursion to photograph wolverines and really appreciated that my 70-200 f4 became a 270mm, that, although it was not too long it was better than a 200mm.

However, first you will loose some quality, this is especially noticeable in the 2x (havent tested but people claim it).
Also, you have not told us what lenses you have. The canon TCs are only compatible with the L tele lenses, due to its front element that literally gets inside the rear part of the lens. Hard to explain but if you have a tele or short tele canon you know what I mean.

So first check out what lenses you have and then decide.

I also have a quite bad Tamron 2x that I rarely use, however I was surprised when I used it with a 300 f4 L, the results were not that bad imo. And it is supposed to be quite bad and cheap.

good luck!

Cant say anything about kenko, or the others as I have never used them.

Victor

 

[Marsu42]

Shooting all kinds of subjects, so no particular purpose for the TC other then "just extending" .

I've got the Kenko 1.4x dgx tc which is "just fine"... in comparison to Canon...

... advantages are a) it fits *every* lens, b) it's smaller, c) it's cheaper, d) af works with f8 (the Canon tcs need a 1d body or a 5d3 with the April (!) 2013 (!) update).

... disadvantages are afaik a) not weather sealed, b) not white :->

IQ seems to be on par with Canon, the latter might be better for some lenses because it moderates (i.e. slows) af speed to give more precise results. But as a "just extend" solution the Kenko is very good, I use it with my 70-300L and 100L macro.

Generally you should stay clear of 2x extenders unless the lens itself is absolutely stellar - otherwise sharpness might be better with cropping, though with higher iso noise.

 

[PeterJ]

Marsu has it pretty well covered. I've got a Canon extender and only added advantage I'd add is that it reports accurate focal length information in the EXIF. A disadvantage I'd add is that with non-EF lenses and any others that don't support the Canon protocol you can't shoot without taping the contacts, it reports a communication problem with the lens.

 

[muldereric]

At this moment I will probably only be using it on my 70-200 f/2.8L IS II USM.
Well since Canon doubled their prices, it's not interesting anymore to stick to that.
The Kenko ones on the other hand are much cheaper! And if they deliver the same results, I can do the math...

In my country (Netherlands) I get these TC's for these prices (converted to USD):
Canon EF 1.4x III Extender for 607,00 USD
Kenko PRO 300 DGX 1.4x for 290,00 USD

Canon EF 2.0x III Extender for 619,00 USD
Kenko PRO 300 DGX 2.0x for 315,00 USD

In both cases it would save me 300+ USD if I would buy the Kenko TC's....

 

[moocowe]

I don't know if this is true of other TC/lens combos, but my Kenko 2x Pro 300 DG is pretty much useless at close focus on my 70-200 IS II.
I'm happy with the sharpness at or near infinite focus, but if you're working near MFD then results are no better than cropping an image from the bare lens.
Only other lens I've used it on is the 100L macro, but that combo had too much fringing for me to use often.

Still, I'd recommend it for the price if you'll be using it at 200mm focussed on distant objects. Sharpness is pretty good with the 70-200 IS II and I've never had any autofocus issues.

Edit: Since I don't use a TC very much and my Kenko only cost me 150 USD brand new, I couldn't justify the price difference for the Canon mkII after seeing reviews where performance difference was negligible to my eyes.

 

[K-amps]

Yes you do lose some IQ with the Canon 2x iii vs the bare lens... but it is:

Better than mk.ii 2x
Better than resampling the image 2x in photoshop taken with bare lens
Better than Kenko 2x
Better than not having a 2x .

If you are price sensitive, don't skimp on a Canon 2x iii, I would get it. However the Kenko 1.4x is not bad compared to the Canon 1.4x, so maybe you can save up on some and get the kenko 1.4x with the Canon 2x iii.

Ideally, both Canon's are better...

 

[Bosman]

If you are extending the reach of a Canon tele I don't think it wise to compromise on the quality of an extender. Can Kenko glass even come close to Canon's optics? I guess we all have our reasoning processes. I just sold my 1.4 II and would prob consider a 2x III for the future if i needed the focal length. Although i can surmise the version III is better than the version II as it is no doubt optimized for the latest L's that work with an extender I wonder about real world testing on the matter. Anyone have data on that?

 

[Ellery Sneed]

It' s allways a dilemma when there are no tests available. Hera is one thou'.
It's in Swedish but the picturecomparison still talks!

It's from a Swedish retailer called Cyberphoto, the best in Sweden, very reliable.

the link:

http://www.cyberphoto.se/info.php?article=128684
Then chose: "Testbilder" (picturesamples)

Glenn

 

[Marsu42]

I've got a Canon extender and only added advantage I'd add is that it reports accurate focal length information in the EXIF.

That's the older dg version, the newer dgx version reports correct exif. There's always a lot of confusion about the different Kenko genrations, just get the latest one

Can Kenko glass even come close to Canon's optics?

That's a definitive "yes" - as for how close they are, from what I've read the 1.4x don't show much of a difference, but everyone can google the reviews for him/herself. Personally, I didn't have a choice anyway since the Canon doesn't fit Canon (the 70-300L) and I really like the Kenko on the 100L macro, too.

 

[K-amps]

Looking at those cyberphoto tests of the fabric side by side... lets keep the sigma out since it was bested by the Canon and the Kenko.

In the 1.4x the center, they are both close. Kenko might be better but too close to call. On the Mid frame to the corners, the kenko is very Mushy and soft... not contest there.

On the 2x: The kenko seems sharper in center and mids, canon better in the corners... it's a Toss overall.

 

[Fotofanten]

Ok, so I am look at the samples from cyberphoto.se, and the Sigma 2x converter looks considerably sharper than the Canon 2x III both at f/5.6 and especially at f/8. Do my eyes deceive me?

 

[GuyF]

I use both the Kenko DG300 1.4x and 2x convertors (not the DGX versions). Kenko does point out that they are designed to be used on fixed focal length lenses above 100mm.

The 1.4x makes no noticeable difference to the sharpness of my 300mm f2.8 IS mk1 although you do see light fall-off in the corners but only if it's a uniformly coloured background i.e. a blue cloudless sky.

The 2x is softer but still quite acceptable (at least to me).

I haven't used the Canon ones but have read there can be compatibility issues with some non-Canon lenses.

I'd suggest the Kenko 1.4x and Canon 2x would be the way to go.

Or you could always walk closer to the subject!

 

[Bosman]

I did do some reading up on this and Canon explains the slower focusing is to increase in-focus accuracy. Makes sense to me.
The 1.4x is 50% slower focus
The 2x is 75% slower focus

 

[moocowe]

I've got a Canon extender and only added advantage I'd add is that it reports accurate focal length information in the EXIF.

That's the older dg version, the newer dgx version reports correct exif. There's always a lot of confusion about the different Kenko genrations, just get the latest one

Strangely, my 3 year old DG version gives me correct EXIF info. l just checked an image and it reports the lens as " EF70-200mm f/2.8L IS II USM +2.0x", focal length as 380mm and max aperture as 5.7.

Is this only because it's a version II lens?

 

[GuyF]

I've got a Canon extender and only added advantage I'd add is that it reports accurate focal length information in the EXIF.

That's the older dg version, the newer dgx version reports correct exif. There's always a lot of confusion about the different Kenko genrations, just get the latest one

Strangely, my 3 year old DG version gives me correct EXIF info. l just checked an image and it reports the lens as " EF70-200mm f/2.8L IS II USM +2.0x", focal length as 380mm and max aperture as 5.7.

Is this only because it's a version II lens?

Hmmm, I'm quite sure my 70-200 f4 IS reports the correct EXIF with either Kenko TC. Certainly my 300mm does. Only with the two stacked do things go off tangent - EXIF only reported for lens plus TC directly attached to it and ignores the one at the body end.

 

[Marsu42]

Strangely, my 3 year old DG version gives me correct EXIF info. l just checked an image and it reports the lens as " EF70-200mm f/2.8L IS II USM +2.0x", focal length as 380mm and max aperture as 5.7. Is this only because it's a version II lens?

As I wrote, the Kenko confusion is growing ... obviously the older "dg" tries to emulate the Canon one by adding +2.0x to the lens info, the newer dgx only modifies the focal length, at least with my 70-300L + 1.4x ... maybe to get around the disabled f8 af.

 

[ahsanford]

My personal experience is limited here, but my thoughts are:

1) Don't buy an extender for just the lenses you have today. Think about what will be in your bag down the road, and with that in mind, get the most compatible tool you can.

2) I own a 2x III and only have one lens (the great 70-200 F/2.8L IS II) that I use it on. Though it's somewhat less sharp than the native glass, you know the argument -- less weight/size to carry, less risk to smuggle into events that you shouldn't bring large glass to (read: sporting events), less heavy/expensive glass not getting used, and far less cost. For me, as an enthusiast (i.e. not a pro), this is an easy decision for the aforementioned reasons, and I love my extender as a result.

3) AF speed with an extender does suffer a bit, so sports may be problematic depending on what you shoot. I've shot baseball with it very well, but I've only been framed on pitchers or batters (which are easy targets) -- hockey, basketball, etc. would likely be a nightmare with one.

4) If you are a pixel peeper, let Bryan Carnathan show you the way...

http://www.the-digital-picture.com/Reviews/Canon-Extender-EF-2x-III-Review.aspx

As always, the good Mr. Carnathan has nice mouseover comparisons of the different extenders. Look about 40% of the way down the page for the sharpness comparison.

Also, he has controlled lab shots with/without extenders here:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687&Camera=453&Sample=0&FLI=3&API=3&LensComp=687&CameraComp=453&SampleComp=0&FLIComp=7&APIComp=2

Feel free to noodle with apertures and extenders (just change focal length, the 1.4 or 2.0 should be obvious based on seeing 280 or 400 on a 70-200 lens). Then mouseover left to right on the graphic to see each. Super useful!

Just my two bits.

- A

 

[bklein61]

MARSU42, I have similar setup. I have the 50D and the 70-300L. I have been tryng to decide on using the 70-300L with the Kenko for wildlife or purchase the 400mm 5.6. Although I am not sure if there is any noticable difference in IQ using the Kenko extender versus the 4005.6 L by itself.

Any thoughts

 

[ahsanford]

MARSU42, I have similar setup. I have the 50D and the 70-300L. I have been tryng to decide on using the 70-300L with the Kenko for wildlife or purchase the 400mm 5.6. Although I am not sure if there is any noticable difference in IQ using the Kenko extender versus the 4005.6 L by itself.

Any thoughts

I've not shot those, but an L prime (even a modestly priced one like the 400 5.6) without an extender should significantly outperform a zoom with an extender, right?

Using that same tool I referred to, comparing almost exactly what you are referring to:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=738&Camera=453&Sample=0&FLI=5&API=1&LensComp=278&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=2

Disclaimer: I don't know what apertures you shoot, and these comparison are only on FF bodies.

Despite the disclaimer, my original guess appears to be in line with the sample shots -- even fully open, the 400 prime seems clearly sharper than the 1.4x F/8 70-300L. Stopping down the 400 prime to the equivalent 'fully open' F/8 of the 1.4x + zoom aperture improves upon this slightly in the corners.

That said [with a fair shrug and hands going up in the air] sharpness isn't everything. What you shoot and what you care about is your business. Telling someone else what they should want in a lens is like telling someone how to raise their kids.

- A