5D3 - 1DX focus speed

Klystron wrote in post #16186405
Ok, different to what I'm trying to do. I'm doing Cycling, motor racing, Canon define this as case 3. Where you move from one subject to another and the AF should change. Tracking a moving target, seems to work.

I suppose its just a bit of trial and error and tweaking? I shot some road cycling on Sunday and in hindsight should have used Case 3. Case 1 didn't work very well. I can't blame the camera. For wildlife and BIF I find Case 1 does the job.

Bones1974 wrote in post #16188225
I suppose its just a bit of trial and error and tweaking? I shot some road cycling on Sunday and in hindsight should have used Case 3. Case 1 didn't work very well. I can't blame the camera. For wildlife and BIF I find Case 1 does the job.

I think I have found the answer, but it has taken some digging.
I use single point focus as I have done on the 7D, with the 5D I should use the expanded AF.
I found it here this is on the Canon DLC, this also applies to the 1Dx.
So I will give it a try. I also found this is a better description of the AF on the 5d and 1Dx

We did some digging on this a few weeks back,. it was news to me

It IS new because ONLY the newest MkII Super telephotos are set up for this advantage, thus a few years back this was NOT true.


Chuck Westfall:
"Lens drive speed: Because of its higher voltage battery, the 1D Mark IV can supply an initial burst of power to select L-series USM telephoto lenses (limited to certain EF super telephotos )* that drives them twice as fast as normal for the first second of operation. The 5D Mark III can't do that because its battery is lower voltage, and also because the camera body is not designed to accept higher voltage even if it was available**."

* so only with some lenses can the 1D big battery actually increase speed.
** which explains why battery grips do not help AF speed. The bodies they attach to can't let the extra power "burst" to the lens.

More links;
http://digitaljournali​st.org/issue0908/tech-tips.html
http://www.ronmartblog​.com …nboxing-first-report.html

This is a question for 2slo (only because I know he has the gear!) how much is the focus speed affected on your 300 2.8 when used with the 2x and 1DX?

is the 85L considered "EF super telephotos"? Because the 85L certainly does focus faster on the 1D bodies vs. anything else.

And the LP-E6 is 7.2V, while the LP-E4N is 11.1V. I'm very rusty with my electrical engineering knowledge but I believe 2x 7.2V battery is still 7.2V.

That would mean with higher battery voltage, less volt drop on the wiring to the lens, and this would help with the start up torque of the motor. If its only to start with.

Klystron wrote in post #16188273
I think I have found the answer, but it has taken some digging.
I use single point focus as I have done on the 7D, with the 5D I should use the expanded AF.
I found it here this is on the Canon DLC, this also applies to the 1Dx.
So I will give it a try. I also found this is a better description of the AF on the 5d and 1Dx

Good find I'll give that a read; anything that can help up the keeper rate is welcome!

jwcdds wrote in post #16188658
is the 85L considered "EF super telephotos"? Because the 85L certainly does focus faster on the 1D bodies vs. anything else.

And the LP-E6 is 7.2V, while the LP-E4N is 11.1V. I'm very rusty with my electrical engineering knowledge but I believe 2x 7.2V battery is still 7.2V.

No, the 85 is not.


2X 7.2 in a camera could likely still be 7.2 with double the amperage.. as the batteries are possibly wired in parallel

But, most electronics that use batteries wire them in series,. in which case amperage remains constant, and it's the voltage that doubles. Thus 4qty 1.5 volt AA in almost any electronics are installed in series to deliver 6volts dc.

Canon could wire the grip in series for 14.4 volts, but the bodies again, are not wired in a way to actually deliver any more power to the lens drive even if you plugged the camera into a stack of car batteries.

CyberDyneSystems wrote in post #16188960
No, the 85 is not.


2X 7.2 in a camera could likely still be 7.2 with double the amperage.. as the batteries are possibly wired in parallel

But, most electronics that use batteries wire them in series,. in which case amperage remains constant, and it's the voltage that doubles. Thus 4qty 1.5 volt AA in almost any electronics are installed in series to deliver 6volts dc.

Canon could wire the grip in series for 14.4 volts, but the bodies again, are not wired in a way to actually deliver any more power to the lens drive even if you plugged the camera into a stack of car batteries.

Ah, thank you for the refresher course. I had forgotten about wiring things in parallel vs. series and how that affects voltage and current.

CyberDyneSystems wrote in post #16188643
We did some digging on this a few weeks back,. it was news to me

It IS new because ONLY the newest MkII Super telephotos are set up for this advantage, thus a few years back this was NOT true.

Chuck Westfall:
"Lens drive speed: Because of its higher voltage battery, the 1D Mark IV can supply an initial burst of power to select L-series USM telephoto lenses (limited to certain EF super telephotos )* that drives them twice as fast as normal for the first second of operation. The 5D Mark III can't do that because its battery is lower voltage, and also because the camera body is not designed to accept higher voltage even if it was available**."

* so only with some lenses can the 1D big battery actually increase speed.
** which explains why battery grips do not help AF speed. The bodies they attach to can't let the extra power "burst" to the lens.

More links;
http://digitaljournali​st.org/issue0908/tech-tips.html
http://www.ronmartblog​.com …nboxing-first-report.html

I was happy with the 5dmk3 but then found this out so bought a 1dx to get the best out of my lens .
Rob.

CyberDyneSystems wrote in post #16188643
We did some digging on this a few weeks back,. it was news to me

It IS new because ONLY the newest MkII Super telephotos are set up for this advantage, thus a few years back this was NOT true.

Where did you get this info from? I can remember Arthur Morris talking about the advantage of the 1D Mark IV higher voltage battery for lens drive speed, this was before the new mkII super teles came out.

nellyle wrote in post #16188657
This is a question for 2slo (only because I know he has the gear!) how much is the focus speed affected on your 300 2.8 when used with the 2x and 1DX?

Very little. It's certainly fast enough for a grab shot at a BiF (as per the Peregrine shot I posted on the 300mm lens thread a week or so ago). I'm not saying it's as fast as the bare lens, the 1Dx + 300mm f/2.8 is as fast at AF as any combination I've tried, but with the 1.4x or 2X TCs (both version III) there isn't much delay at all. I think you'd be pleasantly surprised.

Cameras like the 7D, when using a battery grip with two LP-E6 batteries installed, use these batteries one at a time. They alternate between the two, thus running them both down at about the same rate. That's one of the reasons for the long battery life. The chemistry in one battery gets a chance to recover while the other one is being used, instead of running all the way down to flat in one sequence.