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Gear Talk => Lenses => Topic started by: VitaliD on August 27, 2012, 01:08:11 PM

Title: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: VitaliD on August 27, 2012, 01:08:11 PM
Given that I've definetely decided to buy the Canon 70-200 2.8, what would be the reason for me NOT to buy a 2x teleconverter to cover the up to 400mm range instead of Canon 100-400, apart from the slight aperture advantage at shorter range?
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: Mt Spokane Photography on August 27, 2012, 01:27:23 PM
There are three versions of the 70-200mm f/2.8L, the answer is different for the different versions, but one answer is common, slow autofocus.  The IQ will vary from dismal to almost as good as the 100-400mmL depending on the version.
I think its a waste of money, you will spend $$$ on a TC that is a pain to mount and use, and then, it will only work with f/2.8 lenses and retain AF unless you have a 1 series body up thru the 1D MK IV.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: VitaliD on August 27, 2012, 01:57:52 PM
I am planning to buy the IS Mk2 version - that, I suppose, means that the image quality will be almost the same as with the 100-400.

The "it will only work with f/2.8 lenses and retain AF unless you have a 1 series body up thru the 1D MK IV" can be taken out of equation, because the same applies to the 100-400 lens (aperture difference is small).

Which leaves the following for the 2x extender:

- 1/3 of the price of the 100-400
- more flexibility: ability to use it with other lenses for other applications

and the following against it:

- slightly lower image quality
- slower autofocus
- more cumbersome to mount and use.

The price and flexibility advantages look appealing. I've never used extenders; can you elaborate on "pain to mount and use"? Is it really that bad?
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: jhpeterson on August 27, 2012, 02:06:43 PM
There are three versions of the 70-200mm f/2.8L, the answer is different for the different versions, but one answer is common, slow autofocus.  The IQ will vary from dismal to almost as good as the 100-400mmL depending on the version.
I think its a waste of money, you will spend $$$ on a TC that is a pain to mount and use, and then, it will only work with f/2.8 lenses and retain AF unless you have a 1 series body up thru the 1D MK IV.
I'll beg to differ.
I have both the II version of 70-200/2.8L IS and the 2x EF III. While I'll concede the autofocus speed slows down noticably with the converter on, given decent light, it's still usable for most situations. I'll grant that I don't have much experience with the 100-400, but the IQ, to me, appears almost as good to slightly better with the 70-200/2x combination. However, I found the older version of the IS model was much worse, while the non-IS lens fell somewhere in between.
With the MkII lens and the MkIII converter, I suppose it's a wash and you're paying considerably more money. But , if you planning on working much at 200mm and under, where you'd be using the 70-200 alone, there's absolutely no comparison. Likewise, if you seldom use lengths beyond 300mm, perhaps a better choice would be to get the 1.4x MkIII and cropping for the occasional long shot.
As far as the "pain to mount and use", I suppose you have to ask yourself whether you can spare the 5-10 seconds it will take to make the change.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: Ayelike on August 28, 2012, 06:16:01 AM
I had the 70-200mm f2.8 non-IS but wanted more reach since I've gone full frame. Have toyed with the idea of 100-400mm, 300mm f4 IS and the 400mm f5.6 but have decided to get the 70-200 f2.8 IS II and the Extender 2X III.

The Extender 2X III has arrived today but I'm still waiting for the 70-200mm f2.8 IS II to arrive so I'm unable to share my experiences just yet.

I can say however share my reasons for going down this route:

70-200mm f2.8 IS II is an amazing lens and worth the upgrade from the non-IS version. Sharper and with IS.

100-400mm would only be using this lens in the 200-400mm range as already owned the 70-200mm that does a better job in this range. From what I've seen, the 70-200mm f2.8 IS II with the Extender 2X III is nearly as sharp and still has the IS - will wait and see how the AF performs.

300mm f4 IS - I struggled to justify the cost of this lens at f4 when I could crop a shot from the 70-200mm at f2.8. I think this would be a great lens but I just don't think I'd use it all that much.

400mm f4.6 - this lens is supposed to be really sharp but the lack of IS at that range and speed worried me (I mainly shoot hand-held) and if I wanted to zoom out to compose a shot it would mean a lens change. I think at an event I'm shooing, as I only have one body, I'd be swapping this on and off way too much.

There are so many routes to go down I don't think there is a right and a wrong. You have to find what is best for you I suppose.

My 70-200mm f2.8 IS II should be here in the next few days - I'm also taking this and the Extender 2X III to an airshow in a couple of weeks so I'll let you know my findings after that.

I think the combo is going to be sharp enough for me... at this stage I've just got my fingers crossed that the 5D MKIII will be able to keep the AF tracking through the extender. Watch this space!
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: M.ST on August 28, 2012, 08:05:47 AM
At 400 mm you can focus much faster with the EF 100-400 IS.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: Paul W. H on August 28, 2012, 10:07:11 AM
My wife and I both have 7D's and share lenses including a EF100-400L and a EF70-200L f/2.8 IS MKI.  We also have a Canon 1.4x II and 2.0x II TC and both these work with the 70-200 making it a very versatile lense.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: FarQinell on August 28, 2012, 10:39:31 AM
In a situation like this I always refer to the-digital-picture ISO test charts by Brian Carnahan.

With both lenses wide open @400mm the 100-400L is significantly sharper than the 70-200mm f2.8 II plus Canon TC 2x II.

You have to be desperate to put a 2X TC - even a good one - on any lens! You loose a lot of sharpness and AF speed and the 2XTC is not light in weight either.

My suggestion: wait for the new 100-400L coming down the line - likely to be even sharper than the present one and with a much better IS.

Unfortunately there will be a long waiting list for it!
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: bbasiaga on August 28, 2012, 11:17:30 AM
...and a huge price tag on the new 100-400 too.

I'd look at it this way:  if you are only an occasional shooter at longer than 200mm...then use the TC and save your money.  If you like to do a lot of longer stuff, get the dedicated lens.  Remember that using that TC on any of your other lenses slower than 2.8 renders autofocus inoperable (unless you've got a 1Dmk2,3,4)...so it may not be as versatile as you think.  And really, if you are going to have 70-400 covered already, what other lens are you going to put that TC on anyway? 

-Brian
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: Ayelike on August 28, 2012, 11:29:16 AM
I found this comparison pretty useful:

http://www.canonrumors.com/forum/index.php?topic=5894.msg111941 (http://www.canonrumors.com/forum/index.php?topic=5894.msg111941)

I wouldn't say there was much difference in sharpness between the 100-400 @400 and the 70-200 IS II with 2X III @400 but the 100-400 wins on contrast. I wonder if some RAW processing or post production could fix that though.

I agree with bbasiaga in that if you mainly shoot beyond 200mm then get a lens that has a native range you're after. TCs in my opinion are for occasional times you want more reach and only on sharp and fast lenses.

If I find myself using my TC a lot it'll probably lead me to sell it and get a lens that fits the bill better. But a TC is a good stopgap so you can priorities your money elsewhere.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: VitaliD on August 28, 2012, 11:34:05 AM
And really, if you are going to have 70-400 covered already, what other lens are you going to put that TC on anyway?

Probably none  :)

I agree with you. The flexibility argument hardly applies here; I am very unlikely to use the extender for anything other than 70-200.

Which lives me with the alternative: 1/3 the price VS slightly higher quality and much faster autofocus. In case of the next generation of 100-400, it will probably be 1/4 of the price.

Now I understand what I'll be paying for, how much and for what reasons.

Thank you guys :)
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: K-amps on August 28, 2012, 12:04:18 PM
Hi there:

I was in your position a few months back. Infact I actually owned both side by side for a while and did some tests. (70-200 f2.8 mk.ii + 2x mk.iii  vs. 100-400mm).

I agree there was slightly faster focus with the 100-400, but the f2.8 +Tc was not bad at all. On my 5D3, the AF is still pretty fast , I am able to shoot sports with not a lot of issues with this combo.

Second, the contrast was abit better with the 100-400, but the gradients in the TC combo were better and let me see more details overall. Also the contrast can be tweaked in PP so this was not a huge issue for me.

Third; Sharpness was a toss, but perhaps the 100-400 was slightly better... but not by much. the 2x mk.iii is a huge improvement over the 2x mk.ii so talk to people that have used the mk.iii TC for a more relevant comparison. (unless you plan to buy a 2x ii in which case IQ will take a definite hit)

Fourth: the 100-400 is a large lens... takes up a lot of space in my camera bag, I can store 3 lenses vertically for that 1 slot that the 100-400 takes.

Fifth: Weight. No comparison here.

Sixth: you can use the TC with other lenses also

Lastly you will save about $1000 and not lose a whole lot in IQ, in fact youmight need to pixel peep to see a difference. I am assuming you do not have deep pockets otherwise you'd be getting a 400mm f/2.8 ii.  :D The dedicated lens will always be better but the question is, is it a material difference?

I sold my 100-400 a few weeks back, and have little desire to own one again while I have the 70-200 mk.ii plus TC combo working.

Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: ernieu on August 28, 2012, 12:24:40 PM
I had both, and my experience is that the 70-200 IS II with the 2x II seemed about equal to the 100-400, and in some shots was sharper and more contrasty.  I may have had a bad 100-400.  With the 2x II, the 70-200 IS II was quite slow focusing, even in sunlight - but was acceptable for shooting still images.  I have sold my 100-400 and will probably replace it with a 500 f4 (or the new 100-400, if it rates quite well).

I tend to use my 7D for the longer lenses and 5D MII for the shorter lenses, unless I really need high ISO.  My standard setup is a 24-105 on the 5D II, and the 70-200 on the 7D, giving me basically 24-320 equivalent.  I keep the 2x II handy for longer reach if required.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: Maui5150 on August 28, 2012, 12:47:01 PM
Just shot with the 70-200 F/2.8 IS II and the 2X III and was pleasantly surprised. 

From others I have talked with, the 70-200 II is extremely agile, even with the 2x III, so while it may be a little slower AF, it is not nearly the impact the extender has on some of the other lenses. 

I think the 70-200 II with 2x III still shot faster than the 70-200 F/4

Sharpness was a little down, but also not sure how of that was me shooting action with a 5d MK II so not the best AF system for that

If I wind up doing a lot of shooting at this distance, I will probably go for the 100-400, but would think of nothing renting the extender for a weekend, especially at around $30, very cheap to get the extra reach
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: IIIHobbs on August 28, 2012, 01:28:10 PM
I found the results of having the 1.4xII attached to the Ver I 70-200 f2.8 IS okay.

When switching to a FF Camera earlier this year, I sold the zoom and replaced it with the 300 f4. I liked the results provided by the 300 f4 very much, fast, sharp, excellent for sports.

I initially planned to use the 1.4xII with the 300 f4, but instead sold it and bought a Ver I 300 f2.8 IS. The 300 f2.8 IS with the 1.4xII is an incredible combination.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: K-amps on August 28, 2012, 01:34:34 PM
I found the results of having the 1.4xII attached to the Ver I 70-200 f2.8 IS okay.

When switching to a FF Camera earlier this year, I sold the zoom and replaced it with the 300 f4. I liked the results provided by the 300 f4 very much, fast, sharp, excellent for sports.

I initially planned to use the 1.4xII with the 300 f4, but instead sold it and bought a Ver I 300 f2.8 IS. The 300 f2.8 IS with the 1.4xII is an incredible combination.

Maybe you can rent the Mk.III 1.4x , it might make you even happier than the mk.ii  I hear the improvement is not incremental but in leaps .  :)
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: InterMurph on August 28, 2012, 02:31:28 PM
I went looking for loons in a kayak last week.  I brought my Canon 5D Mark III, 70-200mm f/2.8L II IS USM, and 2x III teleconverter.

Most of the shots were not sharp, but that was clearly due to the motion of the kayak, and the difficulty in holding steady at 400mm.  But I did get many shots like this (400mm, f/5.6, 1/400, ISO 100):

(http://farm9.staticflickr.com/8425/7844946088_66abcd9065_o.jpg) (http://www.flickr.com/photos/martindelvecchio/7844946088/)
Lake Dunmore-2699 (http://www.flickr.com/photos/martindelvecchio/7844946088/#) by Martin Del Vecchio (http://www.flickr.com/people/martindelvecchio/), on Flickr

Here is a 100% crop:

(http://farm9.staticflickr.com/8446/7844975426_a1a08a42f4_o.jpg) (http://www.flickr.com/photos/martindelvecchio/7844975426/)
Lake Dunmore-2699-2 (http://www.flickr.com/photos/martindelvecchio/7844975426/#) by Martin Del Vecchio (http://www.flickr.com/people/martindelvecchio/), on Flickr
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: K-amps on August 28, 2012, 03:43:28 PM
Thats amazing clarity for a TC, lookat that Iris .  Nice shot

A side benefit of the combo is the extra blur your get a wider apertures by merely adding a TC... since you are now shooting at 400mm, you can get very nice background blurs when you want to.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: brianleighty on August 29, 2012, 01:39:34 PM
Thats amazing clarity for a TC, lookat that Iris .  Nice shot

A side benefit of the combo is the extra blur your get a wider apertures by merely adding a TC... since you are now shooting at 400mm, you can get very nice background blurs when you want to.
Just to confirm, you're not saying the 70-200 with 2x TC has a shorter depth of field than the 100-400 at the same aperture and zoom setting correct? Just that 5.6 at 400mm has a smaller depth of field than 5.6 at 200mm correct?
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: castillophotodesign on August 29, 2012, 03:21:42 PM
I was thinking of buying the 100-400 as well but i decided not to. I own the 70-200IS II and TC1.4x & TC2X. I barely  use the 2X because the autofocus seems very slow and the image losses a lot of sharpness. On the other hand, the 1.4X is great. focus is nice and fast and and I see no major change in image quality. here is a shot with the 70-200 and the TC1.4X

(http://farm9.staticflickr.com/8164/7275678430_e61bb24aaa_z.jpg) (http://www.flickr.com/photos/castillophotodesign/7275678430/)
untitled shoot-8479.jpg (http://www.flickr.com/photos/castillophotodesign/7275678430/#) by CastilloPhotoDesign (http://www.flickr.com/people/castillophotodesign/), on Flickr
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: K-amps on August 29, 2012, 04:50:53 PM
Thats amazing clarity for a TC, lookat that Iris .  Nice shot

A side benefit of the combo is the extra blur your get a wider apertures by merely adding a TC... since you are now shooting at 400mm, you can get very nice background blurs when you want to.
Just to confirm, you're not saying the 70-200 with 2x TC has a shorter depth of field than the 100-400 at the same aperture and zoom setting correct? Just that 5.6 at 400mm has a smaller depth of field than 5.6 at 200mm correct?

What I meant was you can get more OOF blur with longer focal lengths...  correct me if I am wrong but adding a TC does not reduce the physical aperture size, which still remains at f2.8 . The physical aperture governs the OOF blur right?

Adding a TC will give you more length and thus more OOF blur. Adding a TC will reduce the light intensity and thus f2.8 becomes f5.6, but it does not close the aperture blades per se, they remain fully /wide open. With the aperture size constant and the focal length double, you lose 2x light intensity but gain 2x OOF blur.

This is how I understand it, and it coincides with experience. Anyone correct me if I am wrong..
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: neuroanatomist on August 29, 2012, 05:18:27 PM
Ok, I'll correct you - you're wrong.  :P

200mm f/2.8 with a 2x TC behaves just like any other 400mm f/5.6 lens in terms of DoF.  Since the 200/2.8+2x magnifies the subject more than a native 200mm, assuming you don't double the distance to the subject, it appears to yield a shallower DoF.  But you are still at f/5.6, and if you framed the subject identically with a native 400/5.6, the DoF would be the same as the 200/2.8+2x, you are not magically getting a 400mm f/2.8 in terms of DoF.

As a side note though, there is a real, lens-dependent effect.  Because a TC does not change the MFD, and the 70-200/2.8 II MFD is about 2 feet closer than that of the 100-400, it is possible to get a closer subject distance with the 70-200+2x than the 100-400, and that does result in a (slightly) shallower DoF, assuming you are shooting at the MFD.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: K-amps on August 29, 2012, 05:47:24 PM
Ok, I'll correct you - you're wrong.  :P

200mm f/2.8 with a 2x TC behaves just like any other 400mm f/5.6 lens in terms of DoF.  Since the 200/2.8+2x magnifies the subject more than a native 200mm, assuming you don't double the distance to the subject, it appears to yield a shallower DoF.  But you are still at f/5.6, and if you framed the subject identically with a native 400/5.6, the DoF would be the same as the 200/2.8+2x, you are not magically getting a 400mm f/2.8 in terms of DoF.

As a side note though, there is a real, lens-dependent effect.  Because a TC does not change the MFD, and the 70-200/2.8 II MFD is about 2 feet closer than that of the 100-400, it is possible to get a closer subject distance with the 70-200+2x than the 100-400, and that does result in a (slightly) shallower DoF, assuming you are shooting at the MFD.

Thanks Neuro...  I am not comparing it to the 400 f5.6 or saying I will get  400 F2.8... Perhaps I did not explain myself better.

 I can use my feet, go back a bit shoot the same framing (by moving back) and get more OOF blur with the TC (200 +TC)  that without (200 without TC) for the same framing ... does this explain my position?
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: adhocphotographer on September 08, 2012, 08:16:07 AM
Hey, this might be a little off topic, but i was hoping someone could chip in with an answer.

I have a 55-250, which i am about to upgrade to a 70-200 IS II (whoooop)...  Does anyone know how the AF compares between the 55-250 and the 70-200 2xTC combo???

I know there are good resources for resolution comparisons, but what about focusing speed comparisons? does anyone know of any?

Thanks
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: M.ST on September 08, 2012, 09:21:44 AM
I prefer the EF 400 2.8 II for or higher for wildlife shots.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: shadowsatnight on September 08, 2012, 10:06:56 AM
Hey, this might be a little off topic, but i was hoping someone could chip in with an answer.

I have a 55-250, which i am about to upgrade to a 70-200 IS II (whoooop)...  Does anyone know how the AF compares between the 55-250 and the 70-200 2xTC combo???

Hi adhoc, I've found (on a 7D) that with the 2xIII, the AF using this combo is still slightly quicker than the 55-250 - providing you've limited the min. focus distance. If you let it go through its full range, takes a similar or possibly slightly longer time to acquire lock.
(to stress though....this is just with the TC on, the lens on its own is V fast to AF. Enjoy it! ).
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: bkorcel on September 08, 2012, 10:41:22 AM
I've used both and I returned the 100-400 in favor of the 70-200 f2.8L IS II and Canon 2X III.  There are a couple of reasons why I did this:

1) AF on the 100-400 was inaccurate with birds in flight on my 60D (What I owned at the time) and often would just fail to lock in time before the shot was gone.  I determined that the 100-400 wide open suffered from slight diffraction issues which interfered with the AF system in both quick mode and live view mode focusing.  It's slight but was enough to cause the AF to fail to lock on accurately enough.  The focus was all over the place.  you could sharpen the image by stopping down some but the AF always works wide open. I tried two copies of the lens and same results.  The 70-200 with the 2X was able to lock on about 90% of the time, the 100-400 about 50% (for birds in flight).  AF speed was a bit faster with the 100-400 but if it cant lock very well, what's the point?

2) The 100-400 is not weather sealed and would often fog on the inside during extreme temperature extremes and high humidity (less of an issue if you didn't "pump" the zoom).  Go from a room with AC to a hot humid summer day and your shoot is ruined for the day.  This was important to me due to the kind of shooting I would use it for...might not be a big issue for some.

3) Removing the 2X gave me another zoom range for closer shots (dual purpose lens) and therefore gets more use than a 100-400 would normally get.

I also purchased the 1.4x III and that has been useful for shooting sports where I can get reasonably close to the action and don't need f2.8.

Going with the 70-200 option is obviously much more expensive so you have to weigh your budget with the cost of getting a higher percentage of keepers.  The good news is that if you take care of your lens you can often get 80% of the value at resale or trade in...so it's possible to go with your budget limits and then upgrade later without taking much of a hit.  Hopefully the 20% can be made up by sales or simply by personal enjoyment during use before you upgrade and take your shots to next level.

Hope this is helpful.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: DigitalDivide on September 08, 2012, 01:08:00 PM
I can use my feet, go back a bit shoot the same framing (by moving back) and get more OOF blur with the TC (200 +TC)  that without (200 without TC) for the same framing ... does this explain my position?

It does explain your position, but unfortunately this is also incorrect :).  Let's assume you are 20 feet from your subject and you are shooting your 200mm wide open for maximum DOF.  At f/2.8 you'll get about 6 inches of DOF.

Now you attach your 2x TC and back up 20 feet to get a 40 foot subject distance for the same framing.  You now have a 400mm f/5.6 lens because of the effect of the TC.  DOF in this case would be double - about 12 inches.  So you actually get a shallower DOF without the TC by staying closer to your subject.

Like many amateurs, I found the whole subject of DOF confusing.  I shot for many years with cheap consumer lenses where it was rarely an issue, but in the last few years I have upgraded to some higher quality glass and I started to notice instances where the DOF was shallower than I anticipated, sometimes enough so to compromise my shot.  To get a better feel for the behavior of my lenses I downloaded a couple of DOF calculator apps for my smartphone, and I fiddle with them from time to time - for example, when I happen to be thinking about a certain shooting situation and I want to know what f stop would work best.  It is also easy to compare the DOF of various lens and TC combinations this way.  There are plenty of examples of DOF calculators on the web as well, such as http://www.outsight.com/hyperfocal.html (http://www.outsight.com/hyperfocal.html).

When the DOF with TC question came up recently, I Googled it and found a lot of very helpful information online which has improved my knowledge of the subject considerably.  DOF is not particularly hard to understand, but there are a lot of misconceptions about what it really means.  It is dependent not only on the fundamental properties of the lens but also on the interaction between the physiology of the human eye and the size of the final image that is being viewed, and it is essential to understand the Circle of Confusion to grasp how it works.  I found the tutorials on the Luminous Landscape website to be invaluable in this regard.
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: adhocphotographer on September 08, 2012, 01:52:39 PM
Hi adhoc, I've found (on a 7D) that with the 2xIII, the AF using this combo is still slightly quicker than the 55-250 - providing you've limited the min. focus distance. If you let it go through its full range, takes a similar or possibly slightly longer time to acquire lock.
(to stress though....this is just with the TC on, the lens on its own is V fast to AF. Enjoy it! ).

Hey, thanks for the info! :) Can't wait to get my hands on it...
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: NJK on October 05, 2012, 11:26:15 AM
I'm pondering the same decision right now.

I don't own either lens yet, but I will be getting the 70-200 2.8 IS mk II soon.  I have the non-L 70-300 IS right now, and I routinely shoot at 300mm.  I would not object to having even more range.  200mm won't cut it for what I do - so I'll either go with the extender 2x mk III or the 100-400.  Obviously, the former solution is cheaper, but if I have to save up a bit longer to get the 100-400 in addition to the 70-200 2.8 IS mk II, then I will.

I understand that the speed of the focus drive is cut by 75% when the extender 2x is used (and by 50% when the 1.4x is used).  I don't do a lot of sports or fast-action shooting (at least not in the 300mm + range), so I can probably live with this.  It sounds like with the (mk II) lens + (mk III) extender at 400mm, IQ is on par with what you get from the 100-400 lens at 400mm.  Yes, you lose 2 stops of light with the extender 2x, which means that either way you go, you will have a maximum aperture of f/5.6 at 400mm.  So, this is really looking like a true "toss up" here.   

I firmly believe in buying lenses with the native focal lengths that you really need, and as I've said, I'm not opposed to saving up a little longer to get the 100-400mm.  BUT, here is what has me leaning in the direction of the 70-200 2.8 IS mk II + the extender 2x mk III, instead of the 100-400:  

(1)  The "drawbacks" in terms of sharpness, IQ, contrast, etc... inherent with any extender are offset by the fact that you're starting with a MUCH higher quality lens (the 70-200 2.8 IS mk II);

(2)  Any issues with contrast can certainly be corrected in PP and the images can also be sharpened a bit in PP, if necessary.  I’m willing to do this work, if lens + extender ends up being the better way to go;

(3)  The 100-400 isn’t (fully) weather sealed, while the 70-200 2.8 IS mk II is weather sealed (as is the extender 2x mk III).  I don't deliberately subject my gear to adverse conditions, but it is nice to know that my investment is protected, if the elements catch me off guard; and     

(4)  The 100-400 only has 2 stops of correction via its IS system, vs. 4 stops of correction via the newer implementation of IS on the 70-200 2.8 IS mk II. 

Point # 4 above is what REALLY has me leaning in this direction.  I don't lug a tripod around with me everywhere.  99% of my shots are hand-held.  DOUBLE the correction (from a more updated IS system) has me thinking that the 70-200 2.8 IS mk II + extender 2x mk III might actually be "better" than buying the 100-400. 

Am I crazy for thinking this?!?  As you can see, I'm aware of the slower focus speed, IQ issues, etc. of going the lens + extender route here.  I didn't see the issue of a much better IS system being discussed in this thread and I just wanted to bring it up.  I'd love to hear your thoughts about this and anyone's actual experience as it relates to the two IS systems here.  Thanks!
Title: Re: 70-200 2.8 + 2x teleconverter vs 100-400
Post by: bkorcel on October 05, 2012, 04:31:45 PM
You are on the right path.  If you are going to get the 70-200 mkii then you wont need the 100-400.  The 200 plus 2xiii extender is all as good as the 100-400.  After using the 70-200 mkII with the 2XIII for a while.  I picked up the 100-400.  Decided to return it as it did not offer me anything I didn't already have.  Plus  the AF was more accurate on the 70-200 with 2xiii.. More keepers shooting birds in flight.  the 100-400 seemed to hunt more for focus and I lost a lot of shots because of it.

I'm pondering the same decision right now.

I don't own either lens yet, but I will be getting the 70-200 2.8 IS mk II soon.  I have the non-L 70-300 IS right now, and I routinely shoot at 300mm.  I would not object to having even more range.  200mm won't cut it for what I do - so I'll either go with the extender 2x mk III or the 100-400.  Obviously, the former solution is cheaper, but if I have to save up a bit longer to get the 100-400 in addition to the 70-200 2.8 IS mk II, then I will.

I understand that the speed of the focus drive is cut by 75% when the extender 2x is used (and by 50% when the 1.4x is used).  I don't do a lot of sports or fast-action shooting (at least not in the 300mm + range), so I can probably live with this.  It sounds like with the (mk II) lens + (mk III) extender at 400mm, IQ is on par with what you get from the 100-400 lens at 400mm.  Yes, you lose 2 stops of light with the extender 2x, which means that either way you go, you will have a maximum aperture of f/5.6 at 400mm.  So, this is really looking like a true "toss up" here.   

I firmly believe in buying lenses with the native focal lengths that you really need, and as I've said, I'm not opposed to saving up a little longer to get the 100-400mm.  BUT, here is what has me leaning in the direction of the 70-200 2.8 IS mk II + the extender 2x mk III, instead of the 100-400:  

(1)  The "drawbacks" in terms of sharpness, IQ, contrast, etc... inherent with any extender are offset by the fact that you're starting with a MUCH higher quality lens (the 70-200 2.8 IS mk II);

(2)  Any issues with contrast can certainly be corrected in PP and the images can also be sharpened a bit in PP, if necessary.  I’m willing to do this work, if lens + extender ends up being the better way to go;

(3)  The 100-400 isn’t (fully) weather sealed, while the 70-200 2.8 IS mk II is weather sealed (as is the extender 2x mk III).  I don't deliberately subject my gear to adverse conditions, but it is nice to know that my investment is protected, if the elements catch me off guard; and     

(4)  The 100-400 only has 2 stops of correction via its IS system, vs. 4 stops of correction via the newer implementation of IS on the 70-200 2.8 IS mk II. 

Point # 4 above is what REALLY has me leaning in this direction.  I don't lug a tripod around with me everywhere.  99% of my shots are hand-held.  DOUBLE the correction (from a more updated IS system) has me thinking that the 70-200 2.8 IS mk II + extender 2x mk III might actually be "better" than buying the 100-400. 

Am I crazy for thinking this?!?  As you can see, I'm aware of the slower focus speed, IQ issues, etc. of going the lens + extender route here.  I didn't see the issue of a much better IS system being discussed in this thread and I just wanted to bring it up.  I'd love to hear your thoughts about this and anyone's actual experience as it relates to the two IS systems here.  Thanks!