Home · Register · Search · View Winners · Software · Hosting · Software · Join Upload & Sell

Moderated by: Fred Miranda
Username   Password

  New fredmiranda.com Mobile Site
  New Feature: SMS Notification alert
  New Feature: Buy & Sell Watchlist
  

FM Forums | Canon Forum | Join Upload & Sell

  

Archive 2012 · 1DX autofocus with extenders at f/8
  
 
jcolwell
Offline
• • • • • • •
Upload & Sell: On
p.1 #1 · p.1 #1 · 1DX autofocus with extenders at f/8


Extenders
- Canon Extender EF 1.4x III
- Kenko Teleplus Pro 300 DG 1.4x AF-C
- Canon Extender EF 2x III

Lenses
- Canon EF 70-200/4 L USM
- Canon EF 70-200/2.8 L IS II USM
- Canon EF 100-400/4.5-5.6L IS
- Canon EF 500/4 L IS USM

Procedure - all handheld shooting, Canon EOS 1DX, firmware v. 1.0.6, One-Shot AF, ISO 800, all tests with lenses wide open, at f/8, start by manual defocusing lens, then attempt to AF on a fairly bright lamp with high contrast details on the lamp shade, at approx 12m distance. The first two example photos show (i) the hallway and (ii) the target lamp. Tests were performed inside today. It was a very overcast day, as there is heavy rain from the remnants of Hurricane Isaac here today. The third example photo shows taped contacts on the 100-400L lens.

Note that the Kenko 'DG' teleconverter I used was purchased in 2009. The contemporary version is 'DGX'. I don't know if they are the same or different in some way. Edit: a recent link posted by Yakim on the 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
thread describes differences between the DG and DGX teleconverters, http://www.fredmiranda.com/forum/topic/1144996/4#10939274

Results

70-200/4L + 2x III
- contacts not taped
no AF
1DX reports f/8
- contacts taped
AF smooth but 'hunts' continuously, poor accuracy
1DX reports f/4

70-200/4L + 1.4x III + 1.4x DG
- contacts not taped
AF smooth and accurate
focus confirmation 'finder flash' active
1DX reports f/5.6
- contacts taped
AF jerky & discontinuous, poor accuracy
1DX reports f/4

70-200/2.8L IS II + 2x III + 1.4x DG
(only possible combination for f/8)
- contacts not taped
AF smooth and accurate
focus confirmation 'finder flash' active
1DX reports f/5.6
- contacts taped
AF smooth but 'hunts' continuously, poor accuracy
1DX reports f/2.8

100-400L + 1.4x III
- contacts not taped
no AF at any focal length
1DX reports f/6.3 at 100mm to f/8 at 400mm
- contacts taped
AF smooth but 'hunts', poor accuracy but sometimes locks on OK
1DX reports f/4.5 at 100mm to f/5.6 at 400mm

100-400L + 1.4x DG
- contacts not taped
no AF at any focal length
1DX reports f/6.3 at 100mm to f/8 at 400mm
- contacts taped
AF smooth and accurate
focus confirmation 'finder flash' active
1DX reports f/4.5 at 100mm to f/5.6 at 400mm

500/4L + 2x III
- contacts not taped
no AF
1DX reports f/8
- contacts taped
AF jerky & discontinuous, no focus lock achieved
1DX reports f/4

500/4L IS + 1.4x III + 1.4x DG,
- contacts not taped
AF smooth, often accurate
focus confirmation 'finder flash' not active
1DX reports f/5.6
- contacts taped
AF jittery, often accurate lock but moves off if AF-ON button held down
focus confirmation 'finder flash' not active
1DX reports f/4

Comment: if I want consistent AF performance at f/8, I'll use my 1D Mark IV.

Edit: new info on Kenko DG vs. DGX teleconverters added to para. 2.
















Edited on Sep 06, 2012 at 01:59 PM · View previous versions



Sep 05, 2012 at 09:01 PM
Geofn
Offline
• • •
Upload & Sell: Off
p.1 #2 · p.1 #2 · 1DX autofocus with extenders at f/8


Very interesting. Thanks for posting.


Sep 05, 2012 at 09:07 PM
Mescalamba
Offline
• • • •
Upload & Sell: Off
p.1 #3 · p.1 #3 · 1DX autofocus with extenders at f/8


If I understand correctly..

Canon intentionally crippled f8 AF via firmware?



Sep 05, 2012 at 09:11 PM
PetKal
Offline
• • • • • • •
Upload & Sell: On
p.1 #4 · p.1 #4 · 1DX autofocus with extenders at f/8


Thank you, Jim, that involved major work, and the results are presented logically and meaningfully.....a great contribution.


Sep 05, 2012 at 09:12 PM
AGeoJO
Offline
• • • • • •
Upload & Sell: On
p.1 #5 · p.1 #5 · 1DX autofocus with extenders at f/8


Jim, thanks for the test. The last picture you depicted, that of your 100-400mm lens, so, did you tape the lens end before you mount the TC on? Not that it matters, I guess, but I taped the TC end where I mounted the lens on.

When I did a more limited testing on my 5D Mark III back then, I noticed that the AF performance was significantly better outdoor in good light then indoor although I turned the light on, too, but I didn't use any lamp to actually focus on though. Based on the images, I assume you did the testing indoor and in the evening?

Joshua



Sep 05, 2012 at 09:25 PM
Lars Johnsson
Offline
• • • • • • •
Upload & Sell: Off
p.1 #6 · p.1 #6 · 1DX autofocus with extenders at f/8


Thanks Jim, good info


Sep 05, 2012 at 09:33 PM
rgold1963
Offline
• •
Upload & Sell: On
p.1 #7 · p.1 #7 · 1DX autofocus with extenders at f/8


Your 500f/4 with the 2XIII behaves exactly as my 400 DO does with the 2XIII. Hopefully Canon will release a firmware update to address this as it seems like the camera is quite capable of focusing at f/8 in somce of your other tests.

Ron



Sep 05, 2012 at 11:01 PM
 

Search in Used Dept. 



Pixel Perfect
Online
• • • • • •
Upload & Sell: On
p.1 #8 · p.1 #8 · 1DX autofocus with extenders at f/8


Great work Jim and as expected. I agree use 1D II/III/IV if you want good AF at f/8

On my 1D II you could get AF at f/11 if you used 400 f/5.6 + Kenko 1.4x + Canon 1.4 or 500 f/4 + Kenko 1.4x + Canon 2x. Haven't tried it on my 1D IV yet.



Sep 05, 2012 at 11:06 PM
AGeoJO
Offline
• • • • • •
Upload & Sell: On
p.1 #9 · p.1 #9 · 1DX autofocus with extenders at f/8


rgold1963 wrote:
Your 500f/4 with the 2XIII behaves exactly as my 400 DO does with the 2XIII. Hopefully Canon will release a firmware update to address this as it seems like the camera is quite capable of focusing at f/8 in somce of your other tests.

Ron



Or just use a 1.4X Mark III in combination with a Kenko 1.4X TC to get an effective focal length multiplier of 2X with your f/4.0 lens, at least for the time being as a work around.


Edited on Sep 05, 2012 at 11:28 PM · View previous versions



Sep 05, 2012 at 11:06 PM
kaycephoto
Offline
• • •
Upload & Sell: Off
p.1 #10 · p.1 #10 · 1DX autofocus with extenders at f/8


thanks for doing the tests & providing the results here Jim! very helpful & much appreciated!

maybe someone else might be able to comment on this question as well, but any comments on the performance (speed vs consistency) & image quality between having 1.4x III + 1.4x DG vs the Canon 2x III on any of the Canon superteles?

(maybe i oughta pose the question as a separate thread?)



Sep 05, 2012 at 11:24 PM
Fred Miranda
Offline
Admin
Upload & Sell: On
p.1 #11 · p.1 #11 · 1DX autofocus with extenders at f/8


"Comment: if I want consistent AF performance at f/8, I'll use my 1D Mark IV."

You nailed it Jim.
If 800mm is not long enough and you can't get closer to your subject to fill the full frame, keep your Mark IV.
After all, the most valuable 1D X improvement over the 1D Mark IV is the new 61-point AF system. Adding third party extenders and shooting at f/8 would greatly reduce any AF advantage.



Sep 05, 2012 at 11:32 PM
PetKal
Offline
• • • • • • •
Upload & Sell: On
p.1 #12 · p.1 #12 · 1DX autofocus with extenders at f/8


Fred Miranda wrote:
You nailed it Jim.
If 800mm is not long enough and you can't get closer to your subject to fill the full frame, keep your Mark IV.
After all, the most valuable 1D X improvement over the 1D Mark IV is the new 61-point AF system. Adding third party extenders and shooting at f/8 would greatly reduce any AF advantage.


Exactly. If we let ourselves become obsessed with that "reach" at the expense of some key qualities this latest technology offers, then might as well use this sorta thing....plenty of "reach" there :


Edited on Sep 07, 2012 at 02:48 AM · View previous versions



Sep 06, 2012 at 12:03 AM
WesN
Offline
• • • •
Upload & Sell: Off
p.1 #13 · p.1 #13 · 1DX autofocus with extenders at f/8


A bit off topic as it involves the 5DIII and a 1.4x TC at f8. Iíve had good success with the 5DIII + 400mm f5.6 + a taped pin Kenko DG 1.4x TC. Note that this was shooting outside with fairly decent light. I saw that you taped your lens here, I have both a Canon 1.4x II and Kenko 1.4x DG. I leave the Kenko permanently taped as Iíll sometimes stack the two TCs with the 500mm f4.

Jim Ė thanks for your testing effort.

Wes N.




Sep 06, 2012 at 01:04 AM
laytonp
Offline

Upload & Sell: Off
p.1 #14 · p.1 #14 · 1DX autofocus with extenders at f/8


Seems as if Canon shot themselves in the foot, by disabling F/8 autofocus in the 1D X. Kenko 1.4x DG teleconverters not "Canon". are selling like hot cakes.


Sep 09, 2012 at 05:33 PM





FM Forums | Canon Forum | Join Upload & Sell

    
 

You are not logged in. Login or Register

Username   Password    Reset password