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Rumors => Lenses => Topic started by: muldereric on November 13, 2012, 03:19:29 AM

Title: Which extender is best
Post by: muldereric on November 13, 2012, 03:19:29 AM
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!
Title: Re: Which extender is best
Post by: Vikmnilu on November 13, 2012, 04:27:32 AM
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
Title: Re: Which extender is best
Post by: Marsu42 on November 13, 2012, 04:45:59 AM
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.
Title: Re: Which extender is best
Post by: PeterJ on November 13, 2012, 05:31:20 AM
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.
Title: Re: Which extender is best
Post by: muldereric on November 13, 2012, 08:11:12 AM
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....
Title: Re: Which extender is best
Post by: moocowe on November 13, 2012, 08:55:51 AM
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.
Title: Re: Which extender is best
Post by: K-amps on November 13, 2012, 09:22:49 AM
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  :P.

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...
Title: Re: Which extender is best
Post by: Bosman on November 13, 2012, 10:44:53 AM
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?
Title: Re: Which extender is best
Post by: Ellery Sneed on November 13, 2012, 12:24:37 PM
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 (http://www.cyberphoto.se/info.php?article=128684)
Then chose: "Testbilder" (picturesamples)

Glenn
Title: Re: Which extender is best
Post by: Marsu42 on November 13, 2012, 12:24:41 PM
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 :-p

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.
Title: Re: Which extender is best
Post by: K-amps on November 13, 2012, 01:15:23 PM
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.
Title: Re: Which extender is best
Post by: Fotofanten on November 13, 2012, 01:39:53 PM
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?
Title: Re: Which extender is best
Post by: GuyF on November 13, 2012, 01:47:38 PM
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!
Title: Re: Which extender is best
Post by: Bosman on November 13, 2012, 01:51:13 PM
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
Title: Re: Which extender is best
Post by: moocowe on November 13, 2012, 01:53:18 PM
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 :-p

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?
Title: Re: Which extender is best
Post by: GuyF on November 13, 2012, 02:06:26 PM
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 :-p

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.
Title: Re: Which extender is best
Post by: Marsu42 on November 13, 2012, 02:58:23 PM
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 :-p ... 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.
Title: Re: Which extender is best
Post by: ahsanford on November 13, 2012, 03:17:12 PM
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 (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 (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
Title: Re: Which extender is best
Post by: bklein61 on November 13, 2012, 04:12:19 PM
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
Title: Re: Which extender is best
Post by: ahsanford on November 13, 2012, 04:43:23 PM
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 (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.   :P

- A
Title: Re: Which extender is best
Post by: Marsu42 on November 14, 2012, 02:38:11 AM
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.
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?

Right. I think the 70-300L rates as "very good" (maybe not "excellent" like the more expensive/heavier/larger 70-200L or even the "stellar" 200L), and with the extender it is just "good". The 400/5.6L should not only be significantly sharper, but the af @f8 with the extender does hunt sometimes if only using one af point on my 60d - so for that reason alone it's better to get the prime. The tc solution for the zoom is just convenience and some shots.
Title: Re: Which extender is best
Post by: ahsanford on November 14, 2012, 02:08:27 PM
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.
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?

Right. I think the 70-300L rates as "very good" (maybe not "excellent" like the more expensive/heavier/larger 70-200L or even the "stellar" 200L), and with the extender it is just "good". The 400/5.6L should not only be significantly sharper, but the af @f8 with the extender does hunt sometimes if only using one af point on my 60d - so for that reason alone it's better to get the prime. The tc solution for the zoom is just convenience and some shots.


Excellent point. 

'Effective' fully open apertures with extenders not only slow AF in general due to a smaller effective aperture (as I said before), but as Marsu42 aptly points out, that smaller aperture also greatly limits what AF points you can use.  Depending on your body + lens + extender choice, your AF will hunt longer before locking on.
Title: Re: Which extender is best
Post by: mrsfotografie on November 14, 2012, 03:32:00 PM
FWIW I have the 1.4 Canon TC II that I use with my 70-200 F/2.8 IS II. Interestingly this combination is supposedly sharper on an APS-C body than the same lens with the new Mk III 1.4 TC, which I'm ready to believe  ;)

http://www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-2.8-L-IS-II-USM-Lens-Review.aspx (http://www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-2.8-L-IS-II-USM-Lens-Review.aspx)

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687)
Title: Re: Which extender is best
Post by: ahsanford on November 14, 2012, 04:00:05 PM
FWIW I have the 1.4 Canon TC II that I use with my 70-200 F/2.8 IS II. Interestingly this combination is supposedly sharper on an APS-C body than the same lens with the new Mk III 1.4 TC, which I'm ready to believe  ;)

http://www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-2.8-L-IS-II-USM-Lens-Review.aspx (http://www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-2.8-L-IS-II-USM-Lens-Review.aspx)

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687)

I believe Carnathan only has 1-3 copies of each lens, whereas a rental shop like LR has (in some cases) a dozen copies or so.  I wonder if there is significant copy to copy variation with Canon Mk III extenders...

(Paging Roger Cicala!)

- A
Title: Re: Which extender is best
Post by: johnf3f on November 15, 2012, 09:15:41 PM
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?

I tried the Sigma 2x vs the Canon Mk2 and found the Canon noticeably better in colour and contrast though pretty similar in sharpness. I later traded The Canon Mk2 2x to get the Mk3. Basically My Canon Mk2 2x was staying at home as I felt cropping was better (remember I found the Sigma significantly inferior to the Canon Mk2) in other words it was a waste of money giving mediocre results on my 300 & 600mm lenses. The Mk3 2x however is enough better to make it worthwhile (it is VERY good on F2.8 primes) to use and carry around. Though very expensive the 2 x Mk3 is significantly better than the Mk2 which was significantly better than the Sigma. Though the Sigma wins hands down on price!
Title: Re: Which extender is best
Post by: RC on November 15, 2012, 09:35:31 PM
At least for Canon TCs, make sure they are compatible with your lens and the lens you plan to buy.  Also keep in mind that for some lens/TC combos, you will lose AF functionality.
Title: Re: Which extender is best
Post by: Fotofanten on December 26, 2012, 07:00:43 PM
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?

I tried the Sigma 2x vs the Canon Mk2 and found the Canon noticeably better in colour and contrast though pretty similar in sharpness. I later traded The Canon Mk2 2x to get the Mk3. Basically My Canon Mk2 2x was staying at home as I felt cropping was better (remember I found the Sigma significantly inferior to the Canon Mk2) in other words it was a waste of money giving mediocre results on my 300 & 600mm lenses. The Mk3 2x however is enough better to make it worthwhile (it is VERY good on F2.8 primes) to use and carry around. Though very expensive the 2 x Mk3 is significantly better than the Mk2 which was significantly better than the Sigma. Though the Sigma wins hands down on price!

Wow, thank you for that insightful post! Much appreciated :)
Title: Re: Which extender is best
Post by: natureshots on December 26, 2012, 10:24:51 PM
I've owned the kenko dgx set, tamron 2x and sigma 2x and I've used the canon.
At 1.4x the kenko is pretty much indistinguishable from the canon mkIII. The kenko works with any lens and the canon with very few lenses. Get the kenko unless you have one of the new mkII canon supertelephoto primes which I'm taking a wild guess is a no.
At 2x the Canon mkIII is substantially better. Kenko comes next, then the canon mkII, then the Tamron and then the sigma which produces mud (and also broke on me in 6 months although it was used/abused very heavily). Make sure your lens can accept the canon 2x if you want the best and can swing the extra $200 for the canon. Also be prepared to make some compromises with the 2x even with the canon. If the light is great and you have good technique you can even get some surprisingly good results with stacked Kenkos. Its less than ideal but I was pretty surprised. If your technique is not so great than you will not be able to stack TCs.
Title: Re: Which extender is best
Post by: East Wind Photography on December 26, 2012, 11:57:16 PM
The 70-200 2.8l II is a very fine lens.  Stick with the canon TCs.  I've used both the 1.4 and the 2x TCs with that lens and the 1.4 loss is negligible.  With the 2x the loss is slight but worth the cost vsa 400mm prime.

The reason I suggest using the canon TCs is that the III version tc's are matched for use with version II lenses.  Using a 3rd party TC will give you slower AF speed and likely lower IQ.  I don't think you will be happy with anything else.  They are more expensive but if you are looking for a matched TC performance my advice would be to stick with the canon TCs. Budget for both the 1.4 and the 2x because you will end up getting both and that's the best choice for expanding the capability of the 70-200 2.8L II lens.

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....
Title: Re: Which extender is best
Post by: bycostello on December 27, 2012, 03:47:22 AM
canon for canon stuff every time...
Title: Re: Which extender is best
Post by: expatinasia on December 27, 2012, 07:05:23 AM
On amazon.co.uk the Kenko 2x Teleplus PRO 300 DGX is £144.99 while the Canon Extender EF 2x III is a staggering £399.

Ironically, there are very few reviews on both, but the Kenko does seem to have a slight "stars" advantage over the Canon, though that may be due to the lower price.

Those about to purchase should definitely read the reviews though as there seems to be a few unhappy 100-400L campers on the Canon section.
Title: Re: Which extender is best
Post by: neuroanatomist on December 27, 2012, 07:26:07 AM
On amazon.co.uk the Kenko 2x Teleplus PRO 300 DGX is £144.99 while the Canon Extender EF 2x III is a staggering £399.

Ironically, there are very few reviews on both, but the Kenko does seem to have a slight "points" advantage, though that may be due to the lower price.

Before the 1D X firmware update providing f/8 AF, Art Morris blogged about getting AF at f/8 with the Kenko 1.4x on the 800/5.6L.  At that time, I had just received my 600/4L II, and really wanted to know if the Kenko 2x would allow f/8 AF with an f/4 lens.  I only found one comparison between the Kenko and Canon 2x TCs, on a birding forum. The guy had shot pics of a US$5 bill with both TCs behind a 500 II - with the Kenko, the bill was very soft, while the Canon 2x was sharp.  Still, it was only one review. I had planned to test the Kenko 2x myself, and in fact, had both the Kenko 2x and 1.4x (for AF with the 100-400) in my B&H cart...but before I got around to clicking Buy, the firmware update was announced, so I bought the Canon 2xIII instead.