Lens focus tracking data

[CanineCandidsByL]

Does anyone know if there is a site that looks at focus tracking in lenses in a measured way instead of just "its fast/slow" or "one 1 in 5 shots has usable focus"?

I'm hoping someone is alternating between targets at different distances and recording change time.  Maybe also using something that moves a target in a repeatable way while firing off photo to see how on/off focus they are?

[prestonpalmer]

Great question.  Id love to see a test like that.  The problem is trying to compare apples to apples.

[briansquibb]

I would love to see that combined with AF times too. I keep seeing remarks about how much faster the 5DIII AF is over the 1D4 - to me the 1D4 is nearly instant so I would love to see some absolute figures

I have also seen comments about how much slower the 5DIII AF is when using automation selection due to the extra points being scanned.

Quite frankly I dont believe either is significant - I would expect no more than a couple of ms either way but it would be nice to know

[Viggo]

A couple of ms is all it takes at f1,2.

I use a lot of the widest apertures available and what surprises me is the difference between the 50 L and the 85 L, while the 85 is obviously slowe, I have more keepers with and my son running due it's insanely good accuracy.

So, yeah, I hope to see what the OP is asking to!

[briansquibb]

A couple of ms is all it takes at f1,2.

Do you mean mm?

[Viggo]

A couple of ms is all it takes at f1,2.

Do you mean mm?

ah, yes...thanks! but maybe also millisceonds of hesitation of the AF I guess.

[lol]

I think part of the reason no one has done it yet is it will be a major pain to setup something that is controlled and repeatable.

[Aglet]

Anyone got a big clean basement, with a large scale race-car track and great lighting?
That's be a somewhat repeatable hardware setup to start with for closer distances.
Otherwise gotta go outside and shoot traffic.

[Viggo]

One could shoot the mechanical rabbit dogs chase at a dog-race?