Does autofocus work when 600mm f/4L IS II USM is used with 2x Teleconverter?

<p>When I used 600mm f/4L IS II USM is used with 1.4x Teleconverter, autofocus works perfectly but when I mount 2x Teleconverter with 600mm f/4L IS II USM, it does not focus. Please suggest.</p>

<p>Which camera?</p>

<p>When you add a 1.4x teleconverter to your f/4.0 lens the effective maximum aperture becomes f/5.6. Many Canon DSLR cameras will autofocus with apertures as small as f/5.6. However, when you add the 2x teleconverter your f/4.0 lens has maximum aperture of f/8.0. Most Canon DSLR cameras cannot autofocus at f/8.0. I know the 5D3 and 1DX can handle autofocus at f/8.0 - but earlier models cannot.<br /> Some might suggest you insulate specific connector pins on the teleconverter so that it cannot tell the camera that the 2x teleconverter is in place. Autofocus may then work at f/8.0 when the light/contrast conditions allow. Also, some third party teleconverters do not communicate their presence to the camera and may work under optimum conditions.</p>

<p>AT http://www.fredmiranda.com/TipsPage/ there are instructions for what Rick describes:</p>

 

<p>The 5D MkIII and the 1D series of bodies will AF at f/8. Anyone that owns a Series II 600/f4 should own one of those bodies to get the most out of their lens. You've spent a fortune on an incredible lens, so don't mess around taping the contacts. Only the top bodies can take full advantage of that lens.</p>

<p>The 5D MkIII has less battery voltage than the 1D series, so with either the 1.4x or the 2.0x TC-III, it's AF slows so much that it's extremely challenging to use for birds in flight, taking up to 1-sec. to lock in, when you use perfect technique. The 1D X slows slightly, but BIF is much, much easier than the 5D MkIII, because the lag is reduced to .1-sec. The 1D MkIV is not quite as quick and flexible as the 1D X, but it's in the same ballpark. I'd really suggest getting the 1D X to go with your super lens.</p>

<p>Perched birds are no problem with the 5D, see below:</p>

<p>1,000mm, handheld, with 5D3:</p>

<p><a title="Kestrel Poses by dcstep, on Flickr" href=" src="http://farm3.staticflickr.com/2805/11919093086_fd3a0c1e4b_c.jpg" alt="Kestrel Poses " width="800" height="800" /></a></p>

<p>OTOH, I was sitting on a ridge this weekend and a bald eagle started flying up toward me. I had a head-on shot with the bird looking up at me, BUT, even after what I thought was a good pre-focus, I couldn't obtain focus. The camera was set properly, in AI Servo mode, but the body didn't have enough juice to yank the lens into focus.</p>

<p>I'm ordering a 1D X on Friday.</p>

<p>Just to give you an idea how incredible the IS is on your Series II lens. Here's a shot with the 500/f4-II and the 1D X (a loaner from CPS), hand held at 1/40-sec:</p>

<p><a title="Waxing Crescent Moon by dcstep, on Flickr" href=" src="http://farm6.staticflickr.com/5476/9489935439_500a128597_c.jpg" alt="Waxing Crescent Moon" width="800" height="800" /></a></p>

<p>Scrap the tripod. You only need it for situations where your focused on one spot for long periods and your arms can't stand it. I'd use my tripod, for instance, if I was staking out a Great Horned Owl's nest, with owlets, or a burrowing owl burrow, etc. Be ready to quickly get the camera off the tripod in case there's a flight shot opportunity, which will be better hand held.</p>

<p>Instead of faffing around with teleconverters or spending a fortune on a 1DX, get a used 7D and keep it in your bag.</p>

<p>Benefits:</p>

<ol>

<li>You'll have an effective 1.6x extender</li>

<li>You can continue to shoot at f/4 instead of f/8 or f/5.6</li>

<li>You won't be degrading the image quality with extra optics</li>

<li>No extenders means AF performance is unaffected</li>

<li>More likely to focus in low light at f/4 compared to f/8</li>

<li>Free back up DSLR included</li>

</ol>

<p>I have recently bought a copy of Reikan FoCal Pro and have been using it to set AFMA for a variety of body, lens and Extender combinations. The data display from the program shows, among other things, how consistently focus is achieved, and it is interesting to note a couple of points – admittedly, in relation to much more modest kit than the 600/4 II.</p>

<p>First, on 7D and 5DIII, AF deteriorates badly with a low-ish battery, long before the battery stops operating the camera. So if you want AF to work well, use a well-charged battery. This is probably a place (?yet another place) where the 1DX has an advantage.</p>

<p>Secondly, the 7D finds 300/4IS×1.4 about as hard to handle as the 5DIII finds 300/4IS×2 (both version II Extenders). In terms of reach (ppd, or pixels per duck) the 7D has about a ×1.4 advantage over the 5DIII, so these are directly comparable alternatives in that respect. Not a great deal to choose between them in terms of IQ on the basis of my test-chart comparisons.</p>

<p>The 7D's AF is two or three generations old and, particularly in the AI Servo mode, it can't keep up with the 5D3. I own both the 7D and the 5D3. When I moved from the 7D to the 5D3, my keeper rate more than doubled, with no change in technique. That's with the bare lens. Add the extenders and the 7D falls even further behind.</p>

<p>Also, the 7D's high ISO performance is not close to the 5D3, much less the 1D X, which is in a high-ISO class all its own. For birds in flight (I'm not sure what our OP will actually be shooting) you're often shooting at ISO 800, which is the point where the 7D does fine, but as you move to ISO 1600 and 3200, the exposure for the 7D becomes super-critical and noise can get nasty fast. (I've shot my 7D with pleasing results up at ISO 6400, but it's just not as easy to use at that ISO as either the 5D3 or 1D X).</p>

<p>The image quality of the EF 1.4x TC-III and the 2.0x TC-III is stunning, as is their AF performance on the 1D X. High quality optical reach beats crop-reach every time.</p>

<p>I love my five-year old 7D, but it's long in the tooth, with an old sensor and an old AF system. When the 7D MkII comes out, hopefully with an updated sensor with better high-ISO performance and the AF system that's in the 1D X and 5D MkIII, then I'll be near the front of the line.</p>

<p>You've invested big money in a super-duper lens. I'd suggest not missing shots because your AF can't keep up or you can't raise the ISO where you need to.</p>

<p>Robin, can you use that Reikan with moving targets? Shooting birds, it's hard to get a "control" sample, because they approach at varying angles and speeds in changing light, but if I took a large sample (like 100+ with each lens/body/extender combination) it might yield meaningful results. Maybe I could set up where gulls or geese are known to repeatedly fly and take a ton of shots testing the AI Servo performance.</p>

<p>I'd love to be able to validate some of my observations gained through field experience.</p>

<p>FYI, I keep my EF 1.4x TC-III on my EF 70-200mm f/4L IS most of the time and find very little latency in AF on my 7D. OTOH, the latency of my 500/f4 plus 2.0X TC-III is HUGE. When I put the 70-200mm plus the 2.0x TC-III on the 5D3, there's a slow down, but nearly so bad as with the 500mm. I suspect it's lens-specific. The mass of the moving parts in the 500mm is probably a big part of the problem.</p>

<p ><a name="00cLbi"></a><a href="/photodb/user?user_id=5331729">David Stephens</a> <a href="/member-status-icons"><img title="Subscriber" src="/v3graphics/member-status-icons/sub5.gif" alt="" /><img title="Frequent poster" src="/v3graphics/member-status-icons/3rolls.gif" alt="" /></a>, Jan 29, 2014; 01:56 p.m.</p>

 

<blockquote>

<p>Robin, can you use that Reikan with moving targets? Shooting birds, it's hard to get a "control" sample, because they approach at varying angles and speeds in changing light, but if I took a large sample (like 100+ with each lens/body/extender combination) it might yield meaningful results. Maybe I could set up where gulls or geese are known to repeatedly fly and take a ton of shots testing the AI Servo performance.</p>

</blockquote>

<p>No. I know of no method of setting up AFMA optimally for moving targets other than trial and error of the kind that you describe. It would certainly be hard to devise a systematic process. The optimal static setting is complicated enough. By default FoCal defocuses the lens towards infinity between harvesting successive data points, but I believe that you can tell it to reverse that and results may not be identical. </p>

 

<p>Thanks Robin. It'd sure be nice to document my observations with empirical numbers.</p>

<p>I've had people tell me that I'm wrong in my observations of the differences between the 5D3 and the 1D X, because the AF time only changes x%. They don't understand that the result can vary very widely with a moving target in changing light, with different backgrounds and different lens. Of course, the people that tell me that have never tried to do it themselves.</p>

Dieter Schaefer : 5D3 it is.

<p>Since you have a 5D3, get the EF 2.0x TC-III and have at it. You'll get lots of great shots. The missed shots will tell you if you need a 1D X or not.</p>

AF was not working with 2x and 600,

was it because of the 5D3 does not

support beyond f8 ?

Will 1DX be the answer to all this problem ?

<p>It should work on the 5D MkIII. Do you have the latest Firmware Update?</p>

<p>As I've state above, the 1D X will be better with the 2.0X TC-III, but it'll only matter for moving subjects.</p>

<blockquote>

<p>The 7D's AF is two or three generations old and, particularly in the AI Servo mode, it can't keep up with the 5D3. </p>

</blockquote>

<p>But he'd be using the 7D without an extender and the 5D3 with an extender. That will even up the AF playing field a little.</p>

 

<blockquote>

<p>Also, the 7D's high ISO performance is not close to the 5D3, much less the 1D X, which is in a high-ISO class all its own.</p>

 

</blockquote>

<p>The 7D will be shooting at f/4, the 5D3 will be shooting at f/8 or f/5.6. Therefore the 7D will be shooting at a lower ISO than the 5D3. Factor in the loss of image quality due to the extra glass of the extender and the image quality of the 5D3 takes a bigger hit.</p>

<p>Page 19 of the EF 600 f/4 IS II USM Manual, second bullet point:</p>

<blockquote>

<p>"With extender EF2x II/III attached to lens, only manual focus is possible. However, with the EOS-1Ds Mark III, EOS-1Ds Mark II, EOS iDs, EOS-1D Mark IV, EOS-1D Mark III, EOS 1D Mark II N, EOS-1D Mark II, EOS 1D, EOS-1V/HS camera, <em>autofocusing with the <strong>center focusing point</strong> is possible.</em>"</p>

</blockquote>

<p>The ability to AF with the center point when using the 2x converter also applies to the 5D Mark III when Firmware 1.2.1 or later is installed. And to the EOS-1D X.</p>

<p>Jamie said:</p>

 

<blockquote>

<p>But he'd be using the 7D without an extender and the 5D3 with an extender. That will even up the AF playing field a little.</p>

</blockquote>

<p>So what? Even with the bare lens, the 7D will not keep up with the 5D MkIII. My keeper rate with the 5D3 and a bare lens is double that with my 7D.</p>

<blockquote>

<p>The 7D will be shooting at f/4, the 5D3 will be shooting at f/8 or f/5.6. Therefore the 7D will be shooting at a lower ISO than the 5D3. Factor in the loss of image quality due to the extra glass of the extender and the image quality of the 5D3 takes a bigger hit.</p>

 

</blockquote>

<p>AF performance trumps ISO performance every time. If the image is OOF, the ISO performance doesn't matter. With the 1.4x TC-III, the 5D MkIII will be in focus and still have a better file in terms of noise. With the 2X at 1200mm, with the 5D3, our OP will have superior optical reach. </p>

<p>The OP already owns the 5D3. No way will he consider a 7D. He might wait for the 7D MkII to see if some of it's issues are fixed with the update.</p>

<blockquote>

<p>AF was not working with 2x and 600, was it because of the 5D3 does not support beyond f8 ?<br>

</p>

</blockquote>

<p>The 5D3 does support AF with f/8 lenses with the current firmware, but the original firmware did not. So you may simply need a firmware update.</p>

<blockquote>

<p>So what? Even with the bare lens, the 7D will not keep up with the 5D MkIII. My keeper rate with the 5D3 and a bare lens is double that with my 7D.</p>

 

</blockquote>

<p>But how's your keeper rate on the 5D3 with a 1.4x or 2x extender compared to a bare lens on the 7D?</p>

 

<blockquote>

<p>With the 2X at 1200mm, with the 5D3, our OP will have superior optical reach.</p>

 

</blockquote>

<p>No he won't. The 7D + 1.4x extender will give 1344mm of focal length at f/5.6 compared to 1200mm at f/8 on the 5D3 using the 2x. </p>

<p>Keeper rate is better with the 1.4 and worse with the 2.0x. IQ is better with the 5D MkIII, in most cases when shooting at ISO 800 and above.</p>

<p>I said optical didn't I, not crop? The actual pixel density increase is not 1.6x. You have to compare pixels on the subject not sensor size. I will say that the 7D is close to the 5DIII when the 1.4x TC-III is attached to the 7D.</p>

<p>The 1D X has even less pixel density, but it's still the best job for this situation.</p>

<p> </p>

<p>Not to divert the thread, but does anyone know the latency of the 5D MKIII with the <a href="http://www.usa.canon.com/cusa/consumer/products/cameras/ef_lens_lineup/ef_200_400mm_f_4l_is_usm_extender_1_4x">EF 200-400mm f/4L IS USM Extender 1.4X</a> and the 1.4x switched on?</p>

<p>Bradford,<br>

I can't offer anything in response to your question. However, it would appear to me that you might get more responses with starting a new thread.<br>

Just sayin . . .</p>

<p>Bradford asked:</p>

<blockquote>

<p>Not to divert the thread, but does anyone know the latency of the 5D MKIII with the <a href="http://www.usa.canon.com/cusa/consumer/products/cameras/ef_lens_lineup/ef_200_400mm_f_4l_is_usm_extender_1_4x" rel="nofollow" target="_blank">EF 200-400mm f/4L IS USM Extender 1.4X</a> and the 1.4x switched on?</p>

</blockquote>

<p>I can't express it quantitatively, but it's hardly noticeable. With the 2.0x TC-III, you start to notice it, but it's not anywhere near as bad as with the 500/f4-5D3 combination. For example, I shot a bunch of skiers, up at Vail, a couple of weekends ago, using the 5D MkIII, the EF 70-200mm f/4L IS and the EF 2.0x TC-III and, with good prefocus, hardly missed a shot. The 1.4x will cause no real problems.</p>