# 5D3 and 24 1.4 II L Edit, and other Lenses, owners please read!



## Louis (May 23, 2013)

Please can you check your camera, in AV Mode and Evaluative Metering, do not move, and switch the lens to manual and back again to Auto AF and please look at your metering value does it change?

It doesn't seem to change with a different lens 

But does with the 24mm

Thanks for your time,


Louis


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## neuroanatomist (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

I'd love to help, but I have neither a 5DIII nor a 24L II. 8)


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## Dianoda (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



Louis said:


> Please can you check your camera, in AV Mode and Evaluative Metering, do not move, and switch the lens to manual and back again to Auto AF and please look at your metering value does it change?
> 
> It doesn't seem to change with a different lens
> 
> ...



I have a 5DIII and 24LII (that exact combo happened to be sitting on my desk when I saw your post...), and can confirm the issue you noted - switching between AF and MF on the lens changed my metering value by 1/3rd of a stop (AF mode was giving me an exposure of 0.3" and MF gave me 1/5) - an odd little quirk, but I don't really consider it to be much of an issue. I'm running the latest firmware if that makes any difference.


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## pedroesteban (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

I'll check when I get home and report... 

Just out of curiosity, how much does your metering change?


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## pwnagepeter (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Same here, just read your post and checked.

Just put it down on a desk and tested what you described:

Can confirm your observation, for me it jumps between 1/30th and 1/40th for the same value of f/1.4 and ISO 1000 for the current light in the room.


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## neuroanatomist (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Just to confirm - _everything_ else is the same with the physical setup? Remember that it's not just what's in front of the camera that matters - light entering through the VF also affects metering so if you're in a different position behind the camera, that can make a difference. Try covering the VF during testing (a lens cap hung over the eyecup does the trick).

Since Live View metering is done using the image sensor rather than the metering sensor, might be good to see if the same phenomenon occurs in live view.


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## Tammy (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

I have that same combination but am currently at work. I will check it out when I go home.

Thank you for bringing this to our attention. I am interested in knowing about any such things about the equipment I've purchased.


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## AE-1Burnham (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

I can report the same thing on a 5D2 and 24 1.4L II... strange and with caveats:
Consistently shifted (on tripod), from 1/60 1.4 to 1/50 1.4 or equivalent. As a silly test, I then changed my focus point selection and then did not see the shift, though when I changed it back to my center focus point the "issue" no longer appeared in this sitting, though I will keep an eye on it. Does not happen with other lenses.

Aren't the newer lenses smarter in terms of where you are focused and communicating that with the camera or am I making this up?

Edit:
I take it back. I was able to repeat the result with the focus point selection, and each time changing the focus point to all made the "issue" go away -- on a 5D Mark II.


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## Dianoda (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



neuroanatomist said:


> Just to confirm - _everything_ else is the same with the physical setup? Remember that it's not just what's in front of the camera that matters - light entering through the VF also affects metering so if you're in a different position behind the camera, that can make a difference. Try covering the VF during testing (a lens cap hung over the eyecup does the trick).
> 
> Since Live View metering is done using the image sensor rather than the metering sensor, might be good to see if the same phenomenon occurs in live view.



The change was directly related to physically moving the AF/MF switch on the lens - shutter speed on the secondary LCD updated instantly as I switched the AF/MF switch (I flipped the switch multiple times a second and shutter speed changed directly in time with each flip of the switch). Viewfinder covered, ISO100, f/2.8 - additionally, this issue does not replicate in LV mode or any other metering mode besides evaluative metering.


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## fredericsiffert (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Hi,

I'am testing now and i haven't a problem...


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## tpatana (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Wow, happens!!!

And live-view it doesn't.

Mark II lens here, it it matters.


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## tpatana (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



neuroanatomist said:


> Just to confirm - _everything_ else is the same with the physical setup? Remember that it's not just what's in front of the camera that matters - light entering through the VF also affects metering so if you're in a different position behind the camera, that can make a difference. Try covering the VF during testing (a lens cap hung over the eyecup does the trick).



I was really careful with this, holding it absolutely one place, keeping my head/eye/hands/everything exactly same position, and AF on I got 1/50-1/60, and 1/40 with MF. Everytime, and switching back and forth it was always 1/50 or 1/60 for AF, and 1/40 for MF. I didn't cover VF though.

And live-view it used 1/60 every time regardless of AF/MF.


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## tpatana (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

More testing, this is getting strange.

I took a lens-cap to cover VF, and it didn't change between AF/MF. Then I removed the lens cap, and still no change. And I'm sure it happened before.

So I turned my camera slightly to take different picture (with different exposure), and the problem came back. I put the lens cap back on VF, and still the problem stayed.

I changed different apertures (1.4....4.5), and the problem stayed. I turned the camera around for different directions, the problem stayed.

I took pictures with AF and MF (1/125 and 1/100), and the histograms for each were as expected, so MF 1/100 had more on the right.

The shutter speed indicator will jump the instant you flick the switch, you don't need to half-press the shutter. So take exposure with AF for 1/125, switch to MF and it changes immediately to 1/100, back to AF and it's 1/125, MF and it's 1/100.

And now no matter what I did, I cannot get it back to "no problem", which I got briefly few minutes ago.

Really strange.

Also no (bright) light shining at the top screen, and my model is anyway newer with the fix.


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## bdunbar79 (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

I just did it. No changes at all at the apertures and ISO's I had.


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## tpatana (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Ok, I did plenty more testing, and now I have theory!

It seems I can find "spots" where it doesn't happen, and then other spots it does (see my post below telling it changed when I moved the camera).

I was able to find spot where the difference was full 1/1 stop. And I was able to find spot where it's exactly same. The "same" happened when the lighting of the area was quite uniform, and the 1/1 stop happened when there were big light differences (shade and sunny spot) in the frame.

Also, I was able to find spots where AF SS was slower, and where MF SS was slower.

So my theory: some reason it uses different spot/area for the evaluation when AF/MF is selected. Let's call them AFS and MFS to help explain. So if AFS hits bright area while MFS hits shaded, it will give MF longer shutter speed. If AFS is on the shade, it'll give longer shutter for AF.

If AFS and MFS areas are similarly illuminated, you don't get difference.


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## tpatana (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Also, I can confirm it happens also with my 70-200. I'm guessing the OP just happened to use 24L so that the AFS and MFS were hitting suitable spots to see the problem.

So it's camera body problem, not lens problem. Something changes on the evaluation based on AF/MF. That is strange indeed. I wonder if Canon knows about that.

Maybe I should conduct more tests...


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## Viggo (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

1d X and 24 L II, nothing changes.


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## iKenndac (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Theory!

Flipping the switch triggers metering. Since evaluative metering invokes code that looks at multiple metering points and tries to intelligently guess what to do, it's somewhat reasonable to assume that it might a different decision on what to do each time it's invoked if the light entering the lens in non-uniform across the image.

A way to test if this is happening is to point the camera so the image is completely uniform in brightness across the image — at the sky, or a flatly coloured wall, etc.

Please bear in mind that I don't own this lens or camera, but I do have experience in programming. In algorithms like this, it's often the case that there's some guesswork involved — hell, I once implemented an algorithm that would just randomly choose one of tho values if it couldn't determine one value over another with any degree of certainty, and it worked just fine.

Since I doubt the camera saves the reasoning behind its metering decisions between each metering, I can easily see this sort of thing happening in something that's supposed to be "smart" like evaluative metering. If you require absolutely consistent metering, I guess evaluative isn't the right mode to choose.


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## neuroanatomist (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



iKenndac said:


> Theory!
> 
> Flipping the switch triggers metering. Since evaluative metering invokes code that looks at multiple metering points and tries to intelligently guess what to do, it's somewhat reasonable to assume that it might a different decision on what to do each time it's invoked if the light entering the lens in non-uniform across the image.
> 
> A way to test if this is happening is to point the camera so the image is completely uniform in brightness across the image — at the sky, or a flatly coloured wall, etc.



This makes perfect sense. Evaluative metering is linked to the selected AF point. Switching to MF deactivates all of the AF points, which means evaluative metering can no longer be weighted toward a selected point. The fact that you're seeing this only with a wide angle lens is not unreasonable. With such a wide FLV, there's more in the scene to affect the metering when it is no longer weighted toward the selected point. 

One way to test this would be simply to change the metering mode to center weighted average, spot, or partial. Doing any of those should eliminate the change with the switch in focusing mode.


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## jdramirez (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



Louis said:


> Thank You for at least replying, sometimes I get the feeling this Forum doesn't want to listen to any problems but to talk mainly about what's new coming out, or how well a Canon did compared to a Nikon vs dropping it
> 
> /sad



I'm sure some people have that exact combo, but not a majority. so if we can't test out out, what benefit would it be for us to post?


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## bdunbar79 (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

This was suggested last night when he frantically posted first, then deleted the whole thread, only to repost.


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## alexturton (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

no changes in exposure on my copy.

This lens is known for having QC. Rife with AFMA and AF accuracy issues.

I had to take my first copy back as it had +15afma and was wildy unpredictable for focus.

My second copy is perfect and is now my favourite lens (over my 85l 1.2 and 70200)


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## tpatana (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Ok, confirmed.

You get the problem if you don't have all AF points selected, and if you select all AF, then the problem goes away.

So depending on AF/MF and AF method/selection, the evaluation formula based on the measurement data is changed. MF will make it back to same formula as with all AF points.


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## Louis (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Thank you for all your replies, its nice to see i'm not going mad, it may not be a big deal, but when i switched to MF yesterday on a shoot, because my model wasn't inline with any 1 of my points, I had to manual focus, and then all my pictures were overexposed when I looked back at the images, I did only think this issue was with my combo 5D3 and 24 1.4 etc, thats why I reposted, but now reading the posts I see its with other lenses also


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## canikon (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

Hello everyone, fisrt time poster here.
The phenomenon described by the OP is related to the strong metering bias that the 5DmkIII has on the selected AF point in evaluative metering.
This is the first thing I noticed coming from a 40D, and is my main complain about 5DmkIII metering algorithm.
When I shoot at night in urban environment, I always switch from evaluative to mean to avoid any strange behaviour of the camera.
In AF mode the level of brightness of the portion of the scene that is caught in the selected AF point area determines the bias in the exposure value.
When "all points" is selected, or when MF selected, this doesn't happen because the camera has no clue about what AF point will be actually used to focus.
This happens on every lens, and is not a flaw in the body, but a choice of the designers of the evaluative metering algorithm that I personally don't like at all.
I'll provide evidence later.
Bye for now.

Update: see the 4 pics attached, made with 135 f/2 L
the AF point is on the light on ceiling, iso is 320 fixed, aperture f/2.0 fixed
pic 1 has AF + eval metering, resulting in 1/4000 sec (strong bias on the AF point, it results effectively in a spot metering on the AF point)
pic 2 has MF + eval metering, resulting in 1/160 sec (the camera has no clue about the AF point in use, and provides a "true" unbiased evaluative metering)
pic 3 has AF + average metering, resulting in 1/160 sec (no bias on mean metering)
pic 4 has MF + average metering, resulting in 1/160 sec 
As you see, in the case AF + evaluative metering the camera attemped not to clip the area of the picture on the selected AF point, thus rendering every other area of the image absolutely meaningless.
The amount of shift in this case is almost 5 stops! 
If I were the designer of this feature, I would let the user to activare or deactivate it, or at least provide a "cap" on the maximum amount of correction allowable, say max 2 stops of bias.
Having it permanently operating as it is, without reasonable cap, means that you have a spot metering on whatever AF point is selected, and this is pretty disturbing to me in certain circumstances.
What do you think about it?


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## bdunbar79 (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



canikon said:


> Hello everyone, fisrt time poster here.
> The phenomenon described by the OP is related to the strong metering bias that the 5DmkIII has on the selected AF point in evaluative metering.
> This is the first thing I noticed coming from a 40D, and is my main complain about 5DmkIII metering algorithm.
> When I shoot at night in urban environment, I always switch from evaluative to mean to avoid any strange behaviour of the camera.
> ...



I also believe that the 1Dx's algorithm is different too, than the 5D3, and I have plenty of evidence to at least suggest that as a possibility.


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## East Wind Photography (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

And dont forget on some models light entering through the top LCD could be a problem.



neuroanatomist said:


> Just to confirm - _everything_ else is the same with the physical setup? Remember that it's not just what's in front of the camera that matters - light entering through the VF also affects metering so if you're in a different position behind the camera, that can make a difference. Try covering the VF during testing (a lens cap hung over the eyecup does the trick).
> 
> Since Live View metering is done using the image sensor rather than the metering sensor, might be good to see if the same phenomenon occurs in live view.


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## luciolepri (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*

I confirm what canikon wrote. At first I thought my camera was defective, but after some tests I understood what was going on: the 5D MKIII gives a very high exposure priority to the metering zone where the AF sets the focus. So, in hi contrast situations, exposure metering results can change a lot, depending on which AF point is in focus.
It would be nice a firmware upgrade to let the user calibrate this metering bias...


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## tpatana (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



canikon said:


> Hello everyone, fisrt time poster here.
> The phenomenon described by the OP is related to the strong metering bias that the 5DmkIII has on the selected AF point in evaluative metering.
> This is the first thing I noticed coming from a 40D, and is my main complain about 5DmkIII metering algorithm.
> When I shoot at night in urban environment, I always switch from evaluative to mean to avoid any strange behaviour of the camera.
> ...



Knowing that, you can also use it to your advantage. E.g. if you know you want bright sign to be exposured correctly, use focus points on that one, and also if you want ambient proper but focus, you can e.g. exposure lock somewhere else and re-compose.

So I don't see that as a disadvantage, after knowing how it works. Not sure if that was mentioned in the manual though.

Also for the OP, I wish I had that much confidence on my skills and gear that I don't chimp the histogram every few picture. If it took you after the shooting to notice over-exposure, maybe next time you should chimp some too?


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## canikon (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



tpatana said:


> Knowing that, you can also use it to your advantage. E.g. if you know you want bright sign to be exposured correctly, use focus points on that one, and also if you want ambient proper but focus, you can e.g. exposure lock somewhere else and re-compose.
> 
> So I don't see that as a disadvantage, after knowing how it works. Not sure if that was mentioned in the manual though.



You are actually right, it is a nice feature when you are doing portraiture in harsh light conditions, provided that you don't AF focus on some dark hair or eyebrow... in that case the exposure is again pretty weird.
All in all, I would prefer at least a "cap" on the amount of shift, otherwise the evaluative metering is not evaluative at all and is more a sort of spot metering on AF point. That is not the way is is marketed by Canon, but it is the way it acts actually. 
Moreover, if you are grabbing a shot quickly you don't have the time to AE lock on the scene and then AF and shoot. This is the reason why when shooting after sunset in urban environment I usually use mean metering, just to avoid that the light of some car or some street lamp could ruin an otherwise perfect shot.
I shoot other Canon and Nikon bodies, a 40D, a 600D, a D800, and I must admit that they have much better and more enjoyable evaluative metering algorithms, and I actually trust those cameras much more than my otherwise beloved 5DmkIII, that actually I trust not at all in high contrast situations.


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## luciolepri (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



tpatana said:


> Knowing that, you can also use it to your advantage. E.g. if you know you want bright sign to be exposured correctly, use focus points on that one, and also if you want ambient proper but focus, you can e.g. exposure lock somewhere else and re-compose.



Well, if you have to do that, what's the point in a "63 Zone Dual-Layer Metering"? Just use the spot exposure!


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## dr croubie (May 23, 2013)

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neuroanatomist said:


> iKenndac said:
> 
> 
> > Theory!
> ...



Theory confirmed, on my 7D & EFs 15-85 as well. Standing outside, with single AF point on the top of the frame, focussing on some bright clouds, in the bottom half of the frame is my neighbour's relatively dark roof. On AF, I get 1/500s. Switch to MF, I get 1/320.

What Neuro said is also applicable to the 7D, metering is weighted more towards what is in focus (in my case, bright sky at infinity). If it doesn't know what's in focus (from being in MF), then it will give even weight to the whole frame and meter more for the dark roof. This is pretty much what the user manual states.

It's not a bug it's a feature.


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## luciolepri (May 23, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



dr croubie said:


> It's not a bug it's a feature.



Yeah, that's just how the exposimeter works with zone metering & AF mode selected, it was like that even with analogic cameras, the point here is that in the 5D Mark III the metering bias is too high.


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## Louis (May 24, 2013)

Great response and i've learnt something thank you! I've never noticed this as i hardly ever shoot manual, anyone know why it seems to be more erratic on my 24 1.4 lens and not my 100mm, ? more testing needed etc

It seems then that the evaluative metering will start from the point of focus, but when switched to manual it will whole scene giving a brighter exposure


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## neuroanatomist (May 24, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



luciolepri said:


> ...in the 5D Mark III the metering bias is too high.


 
I wonder how all the people clamoring for the 5DIII to have AF-point linked spot metering would feel about that observation?


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## Pi (May 24, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



dr croubie said:


> What Neuro said is also applicable to the 7D, metering is weighted more towards what is in focus [...]



This is how Canon's evaluative metering worked since the 300D (at least). I noticed however that my 350D and my 50D were more sensitive to the AF point than my 5D2.


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## Pi (May 24, 2013)

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canikon said:


> I shoot other Canon and Nikon bodies, a 40D, a 600D, a D800, and I must admit that they have much better and more enjoyable evaluative metering algorithms, and I actually trust those cameras much more than my otherwise beloved 5DmkIII, that actually I trust not at all in high contrast situations.



What do you mean by "trust"? You are the one responsible for the exposure. You just need to understand the algorithm and use it appropriately. There is no perfect algorithm and the camera cannot know how you want to expose.


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## LetTheRightLensIn (May 24, 2013)

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iKenndac said:


> Theory!
> 
> Flipping the switch triggers metering. Since evaluative metering invokes code that looks at multiple metering points and tries to intelligently guess what to do, it's somewhat reasonable to assume that it might a different decision on what to do each time it's invoked if the light entering the lens in non-uniform across the image.
> 
> ...



+1


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## risc32 (May 24, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



neuroanatomist said:


> luciolepri said:
> 
> 
> > ...in the 5D Mark III the metering bias is too high.
> ...



To everyone who wanted AF linked spot metering, surprise, you have it!


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## Hobby Shooter (May 24, 2013)

Louis said:


> It seems then that the evaluative metering will start from the point of focus, but when switched to manual it will whole scene giving a brighter exposure


Makes sense


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## tpatana (May 24, 2013)

Does spot metering only use the center circle area?


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## GMCPhotographics (May 24, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



Pi said:


> dr croubie said:
> 
> 
> > What Neuro said is also applicable to the 7D, metering is weighted more towards what is in focus [...]
> ...



Yep my old 5D classic was really AF hotspot prone too. In fact every Canon SLR I've used has always been highlight shy, even my old A-1 film slr. In the Digital world this is a good thing because we should all be shooting to preserve our highlights if possible. 
AF linked metering is a good thing and not a bad thing. Otherwise all our compositions would be centrally placed to match out metering.


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## canikon (May 24, 2013)

*Re: 5D3 and 24 1.4 II L owners please read!!!!!!!!!!!!*



Pi said:


> canikon said:
> 
> 
> > I shoot other Canon and Nikon bodies, a 40D, a 600D, a D800, and I must admit that they have much better and more enjoyable evaluative metering algorithms, and I actually trust those cameras much more than my otherwise beloved 5DmkIII, that actually I trust not at all in high contrast situations.
> ...



You are right, knowing and using the equipment is owner's responsibility. But let me give to you one real example. I was in NYC last year, and at night I suddendly saw a Fire Brigade truck coming full throttle to cope with an emergency, with all the light on, and lots of people staring. I felt it was a nice shot to catch, pulled out my 5DmkIII with 24-105 and fired a couple of shots. Well, both those shots were unfortunate in the sense that the AF point was near or on one of the head light of the truck, and the pic was completely dark except 5 or 6 perfectly exposed head light of the truck. Now that pic was pretty unusable, and a waste.
The real problem is that the designer does not consider two important things:
1. to put a "cap" on the exposure shift, say max 2 stops
2. to consider that with a 63 zone metering system, you cannot distinguish if a light source is wide enough to be "significant" to the photographer, or if it is a 1% of the image area completely irrelevant as in my case was the truck head light.
I assume that 1DX (and D800 as well) having a metering system with 100K points, are far more "intelligent" in knowing if a bright point source is big enough to be of some significance or not.
All in all, this evaluative metering is not evaluative at all, and should be marketed as AF-linked spot meter, giving *another* exposure choice as true evaluative metering option.
Note that in the last 3 images I linked above, the "evaluative" metering when in MF gave the same result as the average metering, so that the evaluative is not "intelligent" or "different" at all, at least in this example.
Tis is my opinion btw, just my feeling about this feature.


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## tpatana (May 24, 2013)

Best would be if they had couple custom metering settings, where (advanced) user could input they own formula how to calculate the exposure based on the information coming from the metering system.


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## alexanderferdinand (May 24, 2013)

I had several cameras, analog, digital.
The 5d3 is the worst one in the discipline "exposure to the left".
Too conservative. A very small bright spot- a very dark file.
(good for high contrast, but .....).

The 1d4 is more honest (?), more intelligent(?).
And so is the Sony RX100.

Didnt notice a difference using af- mf, will watch this in the future.


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## bdunbar79 (May 25, 2013)

tpatana said:


> Does spot metering only use the center circle area?



On a 5D Mark III, yes.


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## tpatana (May 25, 2013)

bdunbar79 said:


> tpatana said:
> 
> 
> > Does spot metering only use the center circle area?
> ...



So to use spot metering on the focus point, you actually have to select evaluative metering. Canon-logic I guess


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## canikon (May 25, 2013)

tpatana said:


> bdunbar79 said:
> 
> 
> > tpatana said:
> ...



Yes exactly, on the 5D mk III actually "Evaluative" metering = AF point "spot" metering. On a low contrast scene you would not notice this, but on a high contrast scene you better to go for the old average metering if you need a consisten "reasonable" exposure. For me even for portrait the AF linked spot metering is not always trustworthy, since if I pick a eyebrow or some dark hair with a focus point, the picture will result blown up overexposed.
I do have a 40D and a 600D, none of them act like this.


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## tpatana (May 25, 2013)

canikon said:


> tpatana said:
> 
> 
> > bdunbar79 said:
> ...



So funny.

Now knowing this, it doesn't really bother me too much as I can use it to my advantage. But not knowing, that might screw up the exposure. I've never trusted the camera anyway too much, I always chimp my pictures constantly.


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