1D3 metering - does this look right?

I usually shoot with manual exposure and spot meter highlights at +3, which seems to work perfectly well for my ETTR raw exposures. Today I was shooting a running dog in varying light and decided to go with Av mode, wide open at f/5.6, 800 ISO and just go with whatever shutter speed I could get. I fired off a test shot with evaluative metering of a field of green grass with EC at 0. Unless the camera has some built in intelligence to know that I was shooting green grass and that should be exposed at -0.5 it looks to me like the camera decided to underexpose the scene. I'd be interested in what others find in a similar situation. Here is the test shot, exactly as shot, and with the histogram clearly showing this scene not to fall at the 0 mark.

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The quirks in 1DS {"built in intel"} both AF and exposure
are the new normal despite Canon claims that both have been fixed.
note the angle of light ...

Although these quirks are often "error" the manufacture will claim
user and how the light strikes sensor and you are left with gazoo.
You wrote that bumper sticker "Sh*t Happens" ??

EL_PIC wrote in post #11839898
The quirks in 1DS {"built in intel"} both AF and exposure
are the new normal despite Canon claims that both have been fixed.
note the angle of light ...

Although these quirks are often "error" the manufacture will claim
user and how the light strikes sensor and you are left with gazoo.
You wrote that bumper sticker "Sh*t Happens" ??

Almost unintelligible garbage.

Almost - because I think I managed to decipher enough of your post to decide it was indeed totally wrong and garbage as well.

Strangely enough the exposures look about right to me.............

To be hones, the first looks about how I would expect it for old grass (fresh one should be brighter) and the last one looks fine to me.

Now the middle one does look underexposed, the question is, what was metered - on that note though, I don't think this is dramatic enough to worry about it. -> You can easily push the centre image to make it a bit brighter without negatively affecting image quality.

I find the 1dmk3 in AV mode to have terrible metering. This is one reason why I claim to many that the metering is finicky. Outdoors it can over and underexpose in a matter of slight minimal contrast change. My 5dc and 5dmk2 seem to have much better metering in AV mode.

I actually dont mind the IQ I get when using studio strobes (consistent light) but for natural light or running and gunning with ETTL I MUST ride the EC or FEC to assure no blowouts or underexposure. This is just "one" of the things I dislike about the 1dmk3. My 1dmk3 focuses perfectly but metering IMO is horrible for natural light portraits. I guess this is where static/non moving subjects its ideal to shoot manual mode since change of scenery is slow. Running and gunning at events AV is much more useful.

The last image was shot at +2/3, which is why it looks OK.

The middle one was metered using evaluative metering. The selected AF point (aided by six assist points) was positioned over the dark fur of the dog. The exposure should have been brighter than that, even without the +1/3 EC for that shot. Look at the histogram. Most of the data is well over to the left, yet I metered from one of the darkest regions of the scene.

I've dumped that shot, but here's another....

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Hmm, strange.

At the same time, the image does seem to have very good detail and no detail loss in the blacks...
Maybe you need to stretch the image across the whole dynamic range in Photoshop?

On that note though - the only people who can give you a definite answer are the folks at Canon as they can theoretically look at the AF algorithm

Tdodd,

Yes I experience the same "crap" with the pro spec 1dmk3.

AlanU wrote in post #11840838
Tdodd,

Yes I experience the same "crap" with the pro spec 1dmk3.

I'm not sure whether to be reassured by that. I've had the camera since new and it is now outside warranty, being over two years old. It's had all the AF checks and oil spot recall, but I can't believe it's taken me till now to discover how bad the metering is. Oh well, back to spot metering and manual exposure for me.

tdodd wrote in post #11840855
I'm not sure whether to be reassured by that. I've had the camera since new and it is now outside warranty, being over two years old. It's had all the AF checks and oil spot recall, but I can't believe it's taken me till now to discover how bad the metering is. Oh well, back to spot metering and manual exposure for me.

My 1dmk3 has had all of the fixes from AF tweeking to sub mirror assembly replacement. The body focuses extremely well and I am very satisfied with that aspect.

I'm being obnoxious at the moment saying "crap". I'll elaborate and say that I find that in AV mode the 1dmk3 for auto exosure the selection of shutter speed is NOT very good. If your a sports shooter with a long tele on a field I think theres less contrast changes to effect the 1dmk3's metering.

Spot metering in manual exposure leaves no decisions made by the camera. This is really the best solution to your "discovery" on how bad the 1dmk3 is in AV mode.

I will say the limited time I've used the 1dmk3 in studio scenarios I find the camera to have great IQ. This is manual mode with "ideal" lighting. Dramatic changing light with the 1dmk3 I find it a struggle to ride the EC and FEC.

DetlevCM wrote in post #11840797
Hmm, strange.

At the same time, the image does seem to have very good detail and no detail loss in the blacks...
Maybe you need to stretch the image across the whole dynamic range in Photoshop?

On that note though - the only people who can give you a definite answer are the folks at Canon as they can theoretically look at the AF algorithm

There is no black clipping, but that's not really the issue. The camera was set up for success, even given a helping hand, and it failed. I don't want to be pushing my files in post. If anything I want to be pulling them. This thread is not about saving the shots - I did that by bumping up the EC to +2/3 or even +1 for most of them - the enquiry is about how/why the camera screwed up so badly and whether that is a common experience. We all know about the 1D3's rep regarding AF, but I've never had any complaints in that department. I was not aware until today that the metering was also under suspicion.

I find I use spot meter or average more with my 1dmk3. Theres an option to force the spot meter to follow your selected focus point. This has helped me in slightl better exposure using that Cfn option.

Tdodd, you are echoing my same concerns and further support my dislike for the AV mode with the 1dmk3.

when i had the mk3 and used Av i would automatically give it +2/3 EV check my histogram and even go as high as +1 1/3 EV with my exposures, you can get great results if you know how to fool the camera.

Interesting. I suppose knowing that that's what you have to do is half the battle, but it seems a bit cockeyed to me to have to dial in +2/3 just to get the camera to expose correctly. It's starting to sound not unlike ETTL-II.

It's like having a car that will drive straight so long as you turn the steering wheel 90 degrees to the right. How many drivers would put up with that?