80-400G Focus Hunting

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First - keep yourself civil, or people will think that there only one idiot. Watch your language and temper. There is no matrix with one already chosen AF sensor(point). Check it first, be mature enough to accept the fact you could be wrong. Look thru VF - single AF point has turned your matrix to SPOT metering. THX! LZ

Sorry i couldnt resist.

and FYI, i know i'm not wrong thank you

right, im looking through the viewfinder, ive selected single point af, im pressing the af-on button to focus and low and behold its still using matrix metering. how do i know this, because the matrix metering symbol is in the bottom corner and also because its just not even concievable that the camera would force you to use spot metering.

Remember back when cameras only had one af point, in the middle, your saying that all the metering modes (matrix, centre weighted etc) were there just for a laugh and only spot metering worked?

Spot metering is only usefull for select scenarios so why would we be forced to use it?

I bet a massive percentage of DSLR users only use one af point now even though they have over 100 on some cameras and your saying that they can only use spot metering?

go have a think about what your saying.
 
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Do what I just suggesting to Randy - simple test for 2-3 min. There is no matrix with one chosen AF sensor(point). Have a great day! LZ
 
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Do what I just suggesting to Randy - simple test for 2-3 min. There is no matrix with one chosen AF sensor(point). Have a great day! LZ

Just tried it on a d810 and in matrix its slightly under exposed as you would think as it thinks all that white is grey so its doing what it would do if you shoot a black dog in snow, you need to apply positive ev to get the whites white rather than 18% grey and if i switch to spot metering its exposing for the black so the whites are over exposed.

For reference ive just tried it on my Canon 1dx mark 2, 5Dsr and Sony A7r2 with similar results.
 
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Very simple test - use any white surface, say, 2x3 meters. Put any dark thing in the middle. Chose any single AF sensor, point it on the middle of the dark area. Set matrix, of course. Final image will be greatly overexposed. Matrix is not working, at all! Clearly visible thru VF, just control parameters and ISO! THX! LZ . PS. I am not mixing any terms, read one more time!
What does this have to do with AF hunting on the 80/400 (the original topic;))
 
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I've checked it in practice. Actor on the scene - always over lit. I must use one AF sensor, to keep him/her in consistent focus. If there was matrix on, the final result will be the actor without face - terribly overexposed. LZ
 
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I've checked it in practice. Actor on the scene - always over lit. I must use one AF sensor, to keep him/her in consistent focus. If there was matrix on, the final result will be the actor without face - terribly overexposed. LZ

and this is the reason why spot metering was invented, why would you be in matrix for a scenario like this?

the different metering modes all have uses, but they are all available no matter what you say.
 
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One more thinking - I am greatly appreciated that function - matrix off with one AF sensor(point) chosen! Just imagine - scene, actor, lightning canons - you know what I mean. So everything must be set to AUTO - one has no time to react on fast changing light. There is my way of filming or shooting concerts - your way will vary, of course. Thank you! LZ
 
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and this is the reason why spot metering was invented, why would you be in matrix for a scenario like this?

the different metering modes all have uses, but they are all available no matter what you say.
You are contradicting to yourself. You said matrix is balanced scene even with spot metering on. It is not. Matrix is completely off with one AF point, doesn't matter what set on camera. Think about what I said about concerting/filming. Try for yourself. Good luck! LZ
 
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You are contradicting to yourself. You said matrix is balanced scene even with spot metering on. It is not. Matrix is completely off with one AF point, doesn't matter what set on camera. Think about what I said about concerting/filming. Try for yourself. Good luck! LZ

No i didnt at all, I said matrix is balancing scene even when spot AF is on (not spot meteing)

Matrix is still in use with spot AF unless you actually change to spot metering, if matrix is selected then matrix is whats in use.

I use matrix metering with single (spot af) all the time for landscape shooting where i want spot af to focus on the main object and matrix meters the scene.

I also use matrix metering with spot af when im shooting a bridal portrait with flash. The flash meters for the subject and matrix metering meters for the background. This way, I can adjust flash exp comp for the bride and i can adjust exp comp for the background to make it darker or brighter.
 
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Chose any AF single point, set camera on matrix, then on spot, take images. There will be not even 1% difference on exposure. It means no matrix at all, with one AF point. The rest is clear demagogue and try to safe face. This dialog is not productive anymore, sorry, I see no sense to continue. THX! LZ
 
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Chose any AF single point, set camera on matrix, then on spot, take images. There will be not even 1% difference on exposure. It means no matrix at all, with one AF point. The rest is clear demagogue and try to safe face. This dialog is not productive anymore, sorry, I see no sense to continue. THX! LZ

Finally we agree on something, if you can't get your head around it then i'm not bothered. End
 
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For what it's worth, I tried the experiment with my D4s, and the results gave me no reason at all to suspect that selecting single point AF enforces spot metering.
 
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28338695931_0ee1379e0d_k.png
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_DSC4580 by longzoom, on Flickr Everything between 2 images is equal. Absolutely. One of them is on spot metering, and next one was on matrix setting. Both are at ISO160, 1/90, f5.3. Extreme left AF sensor(point) was in use. For more info check the EXIF, please. Time difference between them about 10-12 sec. There is very deep shadows, so, matrix image should be lighter. Do you see it? Come on, guys! THX. LZ
 

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So the spot metering point is on a mid-grey area of the image...
Yes, so what? Matrix must read the hole field, and deep shadow in the middle should resulting 1-2 steps difference in exposure. But, as you say, a mid-gray area is under spot metering in both cases, so, no difference is seen. There is no matrix with single AF point, thanks great God! LZ
 
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No, your expectation of what matrix metering does is wrong - what you're describing is simple average metering; matrix does more complex calculations than a simple average.

Point the metering spot at the shadow area and the difference between spot metered and matrix metered exposures will be obvious.

Your scenario where both methods give 'correct' exposure does nothing to prove that one method is inoperative - you need a scenario where one or the other would give a 'wrong' exposure to show that there is (or is not) a difference.
 
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