p.3 #1 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Thought you might be interested that the 70-300 L with the 1.4X TC III at 300mm f/5.6 works in spite of it being at f/5.6. It does not have the extra 3 pins.
1D X, Canon 70-300mm L, f/5.6 with 1.4X TC III (nothing taped)
p.3 #2 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Lars Johnsson wrote:
But he says the camera does not note the TC with it's one stop loss of light. And because of that he have to shoot -1 in the exposure all the time
The explanation of the overexposure is a bit more complicated than a non-reporting TC. A completely non-reporting TC never gives overexposure, because the camera meters through the lens. The relationship between aperture at metering time and aperture at exposure time is always correct, even though the aperture is always one stop smaller than the camera thinks.
The overexposure can only be explained by a mismatch between the reported aperture at metering time, and the calculated aperture at exposure time. The 1DX seems to recognize the TC in parts of the system, but not everywhere.
p.3 #3 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Mickey wrote:
Thought you might be interested that the 70-300 L with the 1.4X TC III at 300mm f/5.6 works in spite of it being at f/5.6. It does not have the extra 3 pins.
1D X, Canon 70-300mm L, f/5.6 with 1.4X TC III (nothing taped)
Very interesting. Canon now have some options:
Confirm that AF will work at F/8 with some lens / TC combinations and leave it at that.
Block AF at F/8 wherever possible in a FW upgrade.
Release AF at F/8 for more lens / TC combinations with a FW upgrade.
Sep 01, 2012 at 03:09 PM
Lars Johnsson Offline • • • • • • • Upload & Sell: Off
p.3 #4 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
alundeb wrote:
The explanation of the overexposure is a bit more complicated than a non-reporting TC. A completely non-reporting TC never gives overexposure, because the camera meters through the lens. The relationship between aperture at metering time and aperture at exposure time is always correct, even though the aperture is always one stop smaller than the camera thinks.
The overexposure can only be explained by a mismatch between the reported aperture at metering time, and the calculated aperture at exposure time. The 1DX seems to recognize the TC in parts of the system, but not everywhere.
Yes I agree with everything you write. The point I was trying to make is that you can't call the TC a "reporting TC" then.
p.3 #5 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Not having anything better to do at this time, I tried to use the combination 1DX + 800L + 1.4xTC MkIII. As I powered the camera up and depressed the shutter button, I was truly astonished by poor AF responsiveness of the setup. Even after 5 or so seconds the setup wouldn't focus. Damn, that thing can not autofocus worth a damn even if its life depended on it.
p.3 #6 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
PetKal wrote:
Not having anything better to do at this time, I tried to use the combination 1DX + 800L + 1.4xTC MkIII. As I powered the camera up and depressed the shutter button, I was truly astonished by poor AF responsiveness of the setup. Even after 5 or so seconds the setup wouldn't focus. Damn, that thing can not autofocus worth a damn even if its life depended on it.
I assume this was with taped pins on the Canon?
So then if we take Artie at his word that the Kenko DGX TC is truly working amazingly, what is the difference between the Kenko and the Canon? Is it purely an optical formula difference between the two converters allowing the light to get to the AF module better with the Kenko? Or is there also an electronical/program component to the difference. Does taping the pins do more than just block the TC recognition?
Sep 01, 2012 at 05:12 PM
Lars Johnsson Offline • • • • • • • Upload & Sell: Off
p.3 #7 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
arbitrage wrote:
I assume this was with taped pins on the Canon?
So then if we take Artie at his word that the Kenko DGX TC is truly working amazingly, what is the difference between the Kenko and the Canon? Is it purely an optical formula difference between the two converters allowing the light to get to the AF module better with the Kenko? Or is there also an electronical/program component to the difference. Does taping the pins do more than just block the TC recognition?
If you take Artie at his word. The Kenko is over-exposing on every shot
p.3 #8 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
arbitrage wrote:
I assume this was with taped pins on the Canon?
No taping, everything was in its stock form . We do know that contact taping has worked for a long time in one form or another, even on prosumer cameras.
p.3 #9 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
PetKal wrote:
No taping, everything was in its stock form . We do know that contact taping has worked for a long time in one form or another, even on prosumer cameras.
Wait a minute. You got AF with the 800L + 1.4x III without taping the pins?
I didn't have a Canon 800L to test this but according to Canon, f/8 AF is not possible... I did try my 500 II + 2x III and it was no-go.
p.3 #10 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Fred Miranda wrote:
Wait a minute. You got AF with the 800L + 1.4x III without taping the pins?
I didn't have a Canon 800L to test this but according to Canon f/8 AF is not possible... I did try my 500 II + 2x III and it was a no-go.
p.3 #11 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Fred Miranda wrote:
Wait a minute. You got AF with the 800L + 1.4x III without taping the pins?
I didn't have a Canon 800L to test this but according to Canon, f/8 AF is not possible... I did try my 500 II + 2x III and it was no-go.
I think maybe Peter was trying to pull a fast one! If you read what he posted he actually never said that it AF at all. Maybe Peter will tape the pins for us and give us an impression of how the AF is in that situation?
p.3 #17 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Another attempt to get the 1Dx to AF at f/8 and it's a no go. Even with the camera reporting the lens at f/4, it seems to want to head right to infinity for focus and stay there. If I manually focus and then hit AF, I can get the AF confirmation light and the focus holds once in a while but most time, it's pulls itself out of focus right away. This was with the 2x III attached and the 400 DO lens.
p.3 #19 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
Yakim Peled wrote:
Any idea why the 1DX can do it while the 5D3 can't?
Happy shooting,
Yakim.
Possibly Canon have code that specifically forbid AF @ f/8 in 5D III, whereas 1D X doesn't so it can at least try. Can't see it having anything to do with the 100000pixel colour sensor array on the 1D X, but that could be another reason.
p.3 #20 · 800mm f/5.6 + 1D-X + 1.4x Extender = Apparently It Can AF!
My 100-400L + 1.4x III does AF on the 1DX with taped pins. The AF is a bit "stepped" (i.e. jumps around, as opposed to smooth changes), but it does work in good light, most of the time.
. We do know that contact taping has worked for a long time in one form or another, even on prosumer cameras.