# D4 AF vs 1d X AF



## Viggo (Jan 5, 2012)

Hi guys! just have a question:

How is it that the Nikon's have only 9 "normal" crosstype, and the Canon has 45 and 5 dual crosstype, and yet they seem to have VERY similar performance, AF-wise. 

The tests done with the D3s and the 1d mkIV they said they were pretty much equal, shouldn't the Canon be WAY better with that much more Cross-type sensors?

And now both the D4 and the 1d X are rated down to -2 EV.


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## Polansky (Jan 5, 2012)

Canon used to have contrast AF detection only on the 1D series. Which measures in 'black and white' so to say. 
While Nikon uses a RGB chip to measure differences in objects and distances. This is why their AF performance is more or less equal.

The 1Dx now seem to have the best AF compared to the D4. Although we can only tell if both camera's have been tested in the field.


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## AprilForever (Jan 5, 2012)

The Canon camera is way, way better. Yes, I know they are still both a dream in the eyes of the faithful, and perhaps some pre-production models, but the Canon one is better!


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## Angryoak (Jan 5, 2012)

AprilForever said:


> The Canon camera is way, way better. Yes, I know they are still both a dream in the eyes of the faithful, and perhaps some pre-production models, but the Canon one is better!



I love canon, and have much invested in glass, but let's hit reality. Nikon has it all over canon with respect to AF, particularly in the prosumer models. 

The 7D was a step in the right direction, but it is very hit and miss on many bodies, with focus points not being aligned with the display points & forward and back focusing on some bodies that apparently is incapable of repair. If the 7Dmk2 can correct this issue of inconsistency, Canon may be able to argue parity with respect to AF with Nikon.

I hate to say this, but there is no point in putting our heads in the sand, as such behaviour will not guide Canon in a direction that will produce a better product. People that are really behind canon, should be duty-bound to loudly point out any deficiencies, or issue that are not acceptable, and only then will Canon's hand be forced and will assist them in to produce a better product in the end.


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## wickidwombat (Jan 5, 2012)

AprilForever said:


> The Canon camera is way, way better. Yes, I know they are still both a dream in the eyes of the faithful, and perhaps some pre-production models, but the Canon one is better!


Um i'm going to assume you meant that as a joke? or have you actually used the nikon AF system? i've used both and when i changed from nikon to canon based on 1Dmk3 performance i was totally unprepared for the 5D af , though after a while you learn to work around it and avoid the pitfalls but it shouldnt be like this, the AF system is critical and i took it for granted that all of canons range would have an acceptable AF system like nikon have. Canon need to pick up their game here and I hope that the new 61 point system is awesome and works perfectly so that the old 45 point system will make it into lower models like the 5d3 its also not about the number of points its about the performance of the points you have.


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## Maui5150 (Jan 5, 2012)

I would not even really mind the AF on the 5D MKII if the AF points had a little more spread than the center focus that they do.


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## 5D Freak (Jan 5, 2012)

I agree about the 5D AF. Centre is awesome, but I would love some cross AF sensors on the outer rim. Doesn't worry me much as I shoot mainly landscape. Sensor performance and RAW quality is important to me.

I have never used a 1D camera, but from what I can gather, you can customize the way the AF works to your needs by mucking around with the custom functions that can be accessed via menu only. It's like customizing the various AF algorithims to suit your needs. If you want the AF to work best for you, you need to sort this out. If I am right, sounds like the AF whiners haven't spent the time in learning these in depth functions to get the best out of their cameras. Less time drinking beer and more time tinkering!

Interesting Canon has had a good crack about overhauling their AF for the 1Dx. I know some have questioned F8 capabilty, but lets see how the package performs once it's released into the wild. Would be interesting to see how the D4 goes, but I don't see either as ship jumping or buyer remorse cameras as both will be awesome!


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## Noink Fanb0i (Jan 5, 2012)

Simple, no one knows because no one as yet has used both side-by-side.


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## EYEONE (Jan 5, 2012)

When they say 9 cross type AF points the have to just be talking about the sensors that go up to F8. The Nikon D3 had 15 cross type sensors. I'd be willing to bet that the AF system in total has much more than 9 CT sensors.


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## neuroanatomist (Jan 5, 2012)

Polansky said:


> Canon used to have contrast AF detection only on the 1D series. Which measures in 'black and white' so to say.
> While Nikon uses a RGB chip to measure differences in objects and distances. This is why their AF performance is more or less equal.



That seems a bit confusing/misleading. Phase detect AF is just that - it detects differences in phase, which are best detected at contrast transitions, but detected much faster. Nikon's AF points are still phase detect AF points. What I think you're trying to say is that previous Nikon cameras used data from the autoexposure sensor to supplement the phase detect AF system, and now the 1D X is doing that, too.



Angryoak said:


> I love canon, and have much invested in glass, but let's hit reality. Nikon has it all over canon with respect to AF, particularly in the prosumer models.



I don't buy this argument. Nikon does not 'have it all over Canon' nor vice versa. Yes, Nikon cameras have more AF points than corresponding Canon cameras, especially in the prosumer segment. But if you believe that the number of points is what determines the effectiveness of an AF system, then do you also believe that the number of MP determines sensor performance, and thus Canon 'has it all over Nikon' in the sensor department? Cross type points are superior to single-orientation points. Nikon's current pro bodies have 51 points with 15 cross-type points. Canon's have 45 points, but 39 of them are cross type, and the Canon cross-type points are distributed across the frame whereas Nikon's are clustered in the center. Furthermore, Canon has f/2.8-sensitive AF points, and the wider triangulation baseline makes those more accurate than f/5.6-sensitive sensors (when used with f/2.8 or fasterlenses, of course) - Nikon has all f/5.6-sensitive points. 

At the prosumer level, i.e. D7000 vs. 7D, again Nikon has more points - 39 vs. 19, but fewer cross-type points (9 vs. 19), and again, no f/2.8-sensitive points. IMO, not even better, let alone 'having it all over Canon.'



Viggo said:


> How is it that the Nikon's have only 9 "normal" crosstype, and the Canon has 45 and 5 dual crosstype, and yet they seem to have VERY similar performance, AF-wise.
> 
> The tests done with the D3s and the 1d mkIV they said they were pretty much equal, shouldn't the Canon be WAY better with that much more Cross-type sensors?



I think you're mixing up your models here. The D3s (and D3x, D3) have 51 total points with 15 cross-type points. The 1D IV has 45 points with 39 cross-type points and no dual cross points. The 1D X has 61 points, of which 41 are cross-type and 5 are dual cross. The D4 spec rumor (and it's still a _rumor_, today at least) is that it will have improved 51 AF points (whatever 'improved' means), and '9 cross-type sensors that are operational up to f/8.' There could be more cross-type sensors at f/5.6, we don't know that yet. An f/8 sensor is going to be less accurate than an f/5.6 sensor, but of course if you have an f/8 lens+TC combo you'll probably take less accurate AF over no AF at all...

Regarding the tests done with the D3s and the 1D IV that said they were pretty much equal, what tests? I've seen comparisons showing the D3s is better, comparisons showing the 1D IV is better, and comparisons showing it's a wash. It all depends on what's being compared, and how. For example, the 1D IV has 39 cross-type points only with an f/2.8 or faster lens. Throw on an f/4 lens and how many cross-type points does the 1D IV have? One. How about with an f/5.6 lens? In that case, the 1D IV has zero cross-type points. None. Zip. Nada. Meanwhile, with any lens down to f/5.6, the D3s still has all 15 of it's cross-type points. Also, even though f/2.8-sensitive points are more accurate, they are slower - for AI Servo tracking of moving subjects, the AF system uses primarily the faster-locking f/5.6 lines. So Nikon, with all it's lines at f/5.6, is going to be able to lock onto moving subjects and track better, especially with the 15 cross-type f/5.6 points clustered in the center, than Canon's single-line points at f/5.6. From that standpoint, even the 7D is better since all 19 of it's AF points are f/5.6-sensitive crosses. But they're more widely spaced and the 1-series has better algorithms, so the 1-series still beats out the 7D.

The 1D X will be a different story. Unlike previous Canon bodies, the 1D X will have 21 cross-type points with most f/5.6 lenses, 41 cross-type points with most f/4 or f/2.8 lenses, plus 5 dual cross-type points with most f/2.8 lenses (but only one with a few, including the 24-70L). So, at the minimum it will have 21 f/5.6 cross-type points in the center (more than the D3s' 15 central f/5.6 crosses). Plus it will use the 100,000 pixel RGB sensor to assist the AF system. 

But in terms of comparing the 1D X to the D4 specs, we'll need to wait until the D4 is officially announced. We'll have to wait even longer for real-world copmparisons, but keep in mind that the lens used will affect the comparison.


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## Viggo (Jan 5, 2012)

neuroanatomist said:


> I think you're mixing up your models here. The D3s (and D3x, D3) have 51 total points with 15 cross-type points. The 1D IV has 45 points with 39 cross-type points and no dual cross points. The 1D X has 61 points, of which 41 are cross-type and 5 are dual cross. The D4 spec rumor (and it's still a _rumor_, today at least) is that it will have improved 51 AF points (whatever 'improved' means), and '9 cross-type sensors that are operational up to f/8.' There could be more cross-type sensors at f/5.6, we don't know that yet. An f/8 sensor is going to be less accurate than an f/5.6 sensor, but of course if you have an f/8 lens+TC combo you'll probably take less accurate AF over no AF at all...
> 
> Regarding the tests done with the D3s and the 1D IV that said they were pretty much equal, what tests? I've seen comparisons showing the D3s is better, comparisons showing the 1D IV is better, and comparisons showing it's a wash. It all depends on what's being compared, and how. For example, the 1D IV has 39 cross-type points only with an f/2.8 or faster lens. Throw on an f/4 lens and how many cross-type points does the 1D IV have? One. How about with an f/5.6 lens? In that case, the 1D IV has zero cross-type points. None. Zip. Nada. Meanwhile, with any lens down to f/5.6, the D3s still has all 15 of it's cross-type points. Also, even though f/2.8-sensitive points are more accurate, they are slower - for AI Servo tracking of moving subjects, the AF system uses primarily the faster-locking f/5.6 lines. So Nikon, with all it's lines at f/5.6, is going to be able to lock onto moving subjects and track better, especially with the 15 cross-type f/5.6 points clustered in the center, than Canon's single-line points at f/5.6. From that standpoint, even the 7D is better since all 19 of it's AF points are f/5.6-sensitive crosses. But they're more widely spaced and the 1-series has better algorithms, so the 1-series still beats out the 7D.
> 
> ...



Excellent, that gives me all the info I needed. For the record, I didn't mix up the models, I just wrote the 1d X and d4 and mk4 and d3s in one long sentence ;D

But your thourough answer, answered all I was wondering about. I just read 9 crosstype, and found it strange.

This, of course, makes the wait for the 1d X that much longer


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## HurtinMinorKey (Jan 5, 2012)

neuroanatomist, teaching people as usual. How do you have so may smites? Do people hate the truth that much?


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## AprilForever (Jan 5, 2012)

HurtinMinorKey said:


> neuroanatomist, teaching people as usual. How do you have so may smites? Do people hate the truth that much?



Telling the truth gets you smitten, always, regardless of what field. In my two non-photographer day jobs, the truth regularly gets the speakers thereof smitten likewise...

But... as the guy asked above, yes, I was kidding in that post! I was referring to the still not yet present 1dX and D4. 

I doubt that there will be any problems with the autofocus of either...


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## traveller (Jan 5, 2012)

HurtinMinorKey said:


> neuroanatomist, teaching people as usual. How do you have so may smites? Do people hate the truth that much?



People just hate it when they're proved wrong, especially in public... 

My two cents? I think that the major AF advantage the D3 series had over previous 1D cameras was the tracking by colour that the meter did. As Neuro states, the 1D X now has this; I wonder if they had to pay Nikon a licensing fee?


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## Picsfor (Jan 5, 2012)

traveller said:


> I wonder if they had to pay Nikon a licensing fee?



Nah, not a hope. Nikon don't have a Digic 4 processor in their arsenal...
And why would Canon compromise when they've apparently got a shed load of Digic 4's to use up 8)


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## briansquibb (Jan 5, 2012)

HurtinMinorKey said:


> neuroanatomist, teaching people as usual. How do you have so may smites? Do people hate the truth that much?



I reckon so by my score :-X :-X :-X

My smiter has another 2 to do by the end of the day - must be one of the APS-C fanbois


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## KeithR (Jan 5, 2012)

traveller said:


> As Neuro states, the 1D X now has this; I wonder if they had to pay Nikon a licensing fee?



Shouldn't think so - the 7D has "colour tracking" too: it incorporates colour data from the metering system into the AF sensor data.

http://www.imaging-resource.com/PRODS/E7D/E7DA.HTM



> The Canon 7D also uses... color information to better identify objects, merging that information with the AF sensor data -- which tells the Canon 7D not only which AF areas are in focus, but which areas are out of focus -- to calculate an object's total range of distances; in that way it can set the aperture to keep that object in focus, if desired.
> 
> The color information also becomes important when trying to focus more accurately when shooting under unusual light sources, like sodium lights, whose unusual spectrum often fools AF systems into backfocusing significantly. When light sources like these are detected, though, the Canon 7D can compensate.



It's not exactly how Nikon use colour data for AF, but I bet it's closer to the 1DX implementation.


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## neuroanatomist (Jan 5, 2012)

KeithR said:


> traveller said:
> 
> 
> > As Neuro states, the 1D X now has this; I wonder if they had to pay Nikon a licensing fee?
> ...



The first statement you quoted sounds like the color imformation is being used to help determine aperture in P and Full Auto modes, and the second statement indicates compensation for wavelengths of light outside of what the AF system is normally calibrated for (recall that phase detect AF sees in monochrome).

Let me excerpt another statement from the review you link:



> Nikon uses this same type of data to track objects moving through the image area, augmenting their continuous focus mode. *Canon does not.*



That suggests that the 7D is not using the color information to support AF in anything similar to how Nikon has, whereas the 1D X is doing exactly what Nikon does - using color data to support AF tracking - and improving it one step further by using that same color information to track specific faces.


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## traveller (Jan 7, 2012)

I've just noticed this about the D4's AF system, from Rob Galbraith's website (http://www.robgalbraith.com/bins/multi_page.asp?cid=7-11673-12223-12224):

_"Autofocus with lenses or lens + teleconverter combos whose maximum aperture exceeds f/5.6. With the D3S, and many other Nikon digital SLR models past and present, attaching something like a 600mm f/4 + 1.7x teleconverter would result in sub-par autofocus or no autofocus, because this combination is beyond the f/5.6 AF limit of most Nikon models. The D4 can autofocus properly to f/8, the first Nikon digital SLR to be rated to do so, as long as your composition keeps the subject relatively close to the centre of the 51-point array.

If the maximum aperture of the lens or combo is between f/5.6 and f/8, the number of AF points that retain their cross-type performance drops to nine, while six others, left and right of centre, operate with single line sensitivity only. The remaining 37 AF points in the array may function, but may not detect focus distance properly if they do.

If the maximum aperture of the lens or combo is f/8, the total number of properly-operating points is 11, with the centre-most AF point retaining its cross-type sensitivity. Other points may function, but might not function well.

Note that the D4 doesn't prevent the user from selecting a non-optimal AF point. If you plan to hook up a long lens and teleconverter that puts you into the beyond-f/5.6 territory, you'll want to pay special attention to which of the 51 AF points work best." _

From what is stated here, it doesn't seem that Nikon have actually made physical changes to the design of the AF sensor to incorporate f/8 sensitive lines, just that they are confident that the AF chip is capable of operating with less light and a smaller 'rangefinder' base length. Perhaps because (_ibid._): 

_"The minimum light level for AF detection, at EV-2, is one stop better than the D3S' EV-1."_ 

So, if the 1D X's AF system is also capable of working at EV-2... (http://cpn.canon-europe.com/content/education/technical/eos_1d_x_af_system_explained.do):

_"The benefits of the new AF system include finer precision and increased AF tracking speed, increased low-light sensitivity down to EV -2"_

Would it be possible for Canon to simply do the same as Nikon and not disable their AF system at f/8 and simply warn users that only the central sensors are likely to be reliable? 

Of course, without actually seeing the D4's AF sensor, we can't know what changes Nikon have actually made to enable f/8 AF, so my logic may be totally wrong! 

Over to Neuroanatomist...?


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## neuroanatomist (Jan 7, 2012)

traveller said:


> Over to Neuroanatomist...?





Noticed and hypothesized on yesterday:

http://www.canonrumors.com/forum/index.php/topic,2707.msg57623.html#msg57623

In short, my take agrees with yours - it's a firmware implementation, and there is a _possibility_ that Canon could match it with the 1D X (if it works well enough with their sensor, and if the choose to (they may not, either for marketing reasons - driving customers to buy longer lenses - or to avoid being seen as reacting directly to the competition).


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## Meh (Jan 7, 2012)

briansquibb said:


> HurtinMinorKey said:
> 
> 
> > neuroanatomist, teaching people as usual. How do you have so may smites? Do people hate the truth that much?
> ...



Neuro gets smited because he's awesome... and maybe because of his sharp wit. You can't please all of the people all of the time.

Brian, you're going to just have to stop telling the truth about the great AF in the 5D2.


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## Meh (Jan 7, 2012)

I think the AF in the 1DX is going to rock. Can't wait to get one. Despite being a costly 1 series, the 1DX is going to be an awesome enthusiast camera. With the best AF, the new RGB meter, and the 18MP sensor that (for an enthusiast) will be the perfect balance of MP and IQ... omg it will be awesome.


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## traveller (Jan 7, 2012)

neuroanatomist said:


> traveller said:
> 
> 
> > Over to Neuroanatomist...?
> ...



Sorry, I missed your post on that thread! Didn't mean to tread on your toes. 

Here's hoping that your "possibility (2)" is correct and that Canon can respond by enabling AF at f/8 in firmware.


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## briansquibb (Jan 7, 2012)

Meh said:


> briansquibb said:
> 
> 
> > HurtinMinorKey said:
> ...



LOL

I am giving up on that - now going to keep telling the 7D people that the 1Ds3 has a better AF than them - and the IQ is better too.

Can justify the extra expense of the 1Ds3 because I save on gym fees by lugging two series 1s around with large whites attached


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## Woody (Jan 8, 2012)

I am keen on Rob Galbraith's test results, assuming he's still willing to test the 1DX after all the flak he received for posting his 1D3/1D4 AF findings.


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## briansquibb (Jan 8, 2012)

briansquibb said:


> Meh said:
> 
> 
> > briansquibb said:
> ...



LOL - got 2 smites for mentioning that again  I expect to be popular when APS-C is relegated to P&S only : : : :


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## traveller (Jan 8, 2012)

Woody said:


> I am keen on Rob Galbraith's test results, assuming he's still willing to test the 1DX after all the flak _*publicity*_ he received for posting his 1D3/1D4 AF findings.


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