5D Mark IV - Set Shutter Lock to only AF not AE in Evaluative Metering

[manatee4mation]

I Canon 5D Mark IV. In evaluative mode, I am trying to half press the shutter to lock the AF but not the AE. By default it locks the AE and AF. I have been through all the settings (custom) and I do not see that option.

And yes I have reviewed the manual and googled this before posting.

I know this had to be a setting. Help!

[manatee4mation]

A number of scenarios. Here are a couple. 1. I set up a shot. Shallow focus. Non-studio setting. Natural light. I get just the right focus. I want something interesting to happen. A butterfly enter the scene, for example. The moment that happens. Snap the pic. Need metering to remain fluid.  2. I focus. Move the camera to change the framing. Keep the focus. Have the metering update.  

And, yes, under both of these I can use the BBs, but I don't want to have to.

BTW, I lived in Wellesley for 17 years.

[RobertTheFat]

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@manatee4mation wrote:

A number of scenarios. Here are a couple. 1. I set up a shot. Shallow focus. Non-studio setting. Natural light. I get just the right focus. I want something interesting to happen. A butterfly enter the scene, for example. The moment that happens. Snap the pic. Need metering to remain fluid.  2. I focus. Move the camera to change the framing. Keep the focus. Have the metering update.  

And, yes, under both of these I can use the BBs, but I don't want to have to.

BTW, I lived in Wellesley for 17 years.

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You can set the metering timer to as much as 30 minutes. Would that have, for all practical purposes, the effect you're seeking? The many references to the metering timer in the manual leave the question open as to whether that setting applies to the act of metering itself or just to the time it's displayed. But if the latter, it's still at least possible that metering continues for as long as the shutter button is depressed. The fact that metering can't be completely decoupled from the shutter button strikes me as possible evidence for that explanation. Bottom line: Do you actually have any hard evidence that the default behavior isn't what you want? Note that the description assigned to half-depression of the shutter button is "Metering and AF start". The word "stop" or "lock" is not used. As far as I can see, the only button that "locks" AE by default is the "*" button.

Can you believe that the spellchecker objects to the correct spelling of "Wellesley"?

EDIT:  Since I first wrote this, I've been googling around to see if I could discover what the metering timer actually does. The answer seems to be that nobody knows for sure. There are those who think they do, but their explanations are wildly contradictory and devoid of proof. Some agree with me, sort of, but not enough to give me any real confidence. For lack of anything better, I guess I'll stick with my explanation (such as it is) for now. But in the absence of an unlikely intervention by Canon, I think the only way to get better information is by experimentation.

[manatee4mation]

Thanks for all your help.

I spoke to Canon and they were adamant that there is no way to get around the "meter shutter lock." Their term.  

As for the meter timer, another easy thing to test. You start the metering process with a quick half press. You lock the meter with a half-press and hold.  The timer is merely the time the meter stays active from the half-step tap-and-release to the half-shutter hold. Super easy to test. Not sure why anyone thinks this is controversial.

All of this is easy to test. Any Canon DSLR.

Point at a dark area, press the shutter half way down, note the exposure, move the camera to see  a bright area and look at the meter. It does not change. Now snap the shot and look at the metadata - you will see the same exposure you locked. You have to test this in AIFocus and Single shot.  By defiinition, AIServo refocuses and when it does, it remeters - effectlvekly negates your original half-press and hold.

Wish it was not so.

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@RobertTheFat wrote:

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@manatee4mation wrote:

A number of scenarios. Here are a couple. 1. I set up a shot. Shallow focus. Non-studio setting. Natural light. I get just the right focus. I want something interesting to happen. A butterfly enter the scene, for example. The moment that happens. Snap the pic. Need metering to remain fluid.  2. I focus. Move the camera to change the framing. Keep the focus. Have the metering update.  

And, yes, under both of these I can use the BBs, but I don't want to have to.

BTW, I lived in Wellesley for 17 years.

---

You can set the metering timer to as much as 30 minutes. Would that have, for all practical purposes, the effect you're seeking? The many references to the metering timer in the manual leave the question open as to whether that setting applies to the act of metering itself or just to the time it's displayed. But if the latter, it's still at least possible that metering continues for as long as the shutter button is depressed. The fact that metering can't be completely decoupled from the shutter button strikes me as possible evidence for that explanation. Bottom line: Do you actually have any hard evidence that the default behavior isn't what you want? Note that the description assigned to half-depression of the shutter button is "Metering and AF start". The word "stop" or "lock" is not used. As far as I can see, the only button that "locks" AE by default is the "*" button.

Can you believe that the spellchecker objects to the correct spelling of "Wellesley"?

EDIT:  Since I first wrote this, I've been googling around to see if I could discover what the metering timer actually does. The answer seems to be that nobody knows for sure. There are those who think they do, but their explanations are wildly contradictory and devoid of proof. Some agree with me, sort of, but not enough to give me any real confidence. For lack of anything better, I guess I'll stick with my explanation (such as it is) for now. But in the absence of an unlikely intervention by Canon, I think the only way to get better information is by experimentation.

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[manatee4mation]

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@RobertTheFat wrote:

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@manatee4mation wrote:

A number of scenarios. Here are a couple. 1. I set up a shot. Shallow focus. Non-studio setting. Natural light. I get just the right focus. I want something interesting to happen. A butterfly enter the scene, for example. The moment that happens. Snap the pic. Need metering to remain fluid.  2. I focus. Move the camera to change the framing. Keep the focus. Have the metering update.  

And, yes, under both of these I can use the BBs, but I don't want to have to.

BTW, I lived in Wellesley for 17 years.

---

You can set the metering timer to as much as 30 minutes. Would that have, for all practical purposes, the effect you're seeking? The many references to the metering timer in the manual leave the question open as to whether that setting applies to the act of metering itself or just to the time it's displayed. But if the latter, it's still at least possible that metering continues for as long as the shutter button is depressed. The fact that metering can't be completely decoupled from the shutter button strikes me as possible evidence for that explanation. Bottom line: Do you actually have any hard evidence that the default behavior isn't what you want? Note that the description assigned to half-depression of the shutter button is "Metering and AF start". The word "stop" or "lock" is not used. As far as I can see, the only button that "locks" AE by default is the "*" button.

Can you believe that the spellchecker objects to the correct spelling of "Wellesley"?

EDIT:  Since I first wrote this, I've been googling around to see if I could discover what the metering timer actually does. The answer seems to be that nobody knows for sure. There are those who think they do, but their explanations are wildly contradictory and devoid of proof. Some agree with me, sort of, but not enough to give me any real confidence. For lack of anything better, I guess I'll stick with my explanation (such as it is) for now. But in the absence of an unlikely intervention by Canon, I think the only way to get better information is by experimentation.

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The meter timer has nothing to do with the AE lock on half-shutter. Meter timing is a battery saving setting. It defaults to be a very quick 6 seconds so the camera can get the maximum battery life. 

Here is how meter timing works.

1. Half press the shutter and release. The meter is now active for the length of the meter timing setting.

2. Half press the shutter and hold . Exposure meter is locked.

Anyone with any Canon DSLR can test this out.

[RobertTheFat]

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@manatee4mation wrote:

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The meter timer has nothing to do with the AE lock on half-shutter. Meter timing is a battery saving setting. It defaults to be a very quick 6 seconds so the camera can get the maximum battery life. 

Here is how meter timing works.

1. Half press the shutter and release. The meter is now active for the length of the meter timing setting.

2. Half press the shutter and hold . Exposure meter is locked.

Anyone with any Canon DSLR can test this out.

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Can you point us to any supporting Canon documentation? I've yet to run across anything by Canon that mentions the metering timer and battery life in the same paragraph.

Incidentally, the instruction manual says that the metering timeout on a 5D4 is four seconds, not six. On a 5D3 I surmise that it's 10 seconds, because that's what mine is set to and I can't think of a reason why I would have changed it.

[manatee4mation]

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@RobertTheFat wrote:

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@manatee4mation wrote:

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The meter timer has nothing to do with the AE lock on half-shutter. Meter timing is a battery saving setting. It defaults to be a very quick 6 seconds so the camera can get the maximum battery life. 

Here is how meter timing works.

1. Half press the shutter and release. The meter is now active for the length of the meter timing setting.

2. Half press the shutter and hold . Exposure meter is locked.

Anyone with any Canon DSLR can test this out.

---

Can you point us to any supporting Canon documentation? I've yet to run across anything by Canon that mentions the metering timer and battery life in the same paragraph.

Incidentally, the instruction manual says that the metering timeout on a 5D4 is four seconds, not six. On a 5D3 I surmise that it's 10 seconds, because that's what mine is set to and I can't think of a reason why I would have changed it.

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Hi Bob,

You are right about the default metering timer. 5D4 is four seconds. I was wrong.  I had read in a review a while back that that metering timer is a battery life issue. Nothing that i know of in the manual.

On my underlying issue, see page 100 of the 5D4 manual.

• With evaluative metering (p.253), the exposure setting will be set at the same time as focus is achieved.

•  While you hold down the shutter button halfway, the focus will be locked. You can then recompose the shot if desired.

This looks like a dead horse. Unless I convnce Canon to act like Nikon and offer the custom control I want, I will have to use the back button controls.

[Waddizzle]

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@manatee4mation wrote:

A number of scenarios. Here are a couple. 1. I set up a shot. Shallow focus. Non-studio setting. Natural light. I get just the right focus. I want something interesting to happen. A butterfly enter the scene, for example. The moment that happens. Snap the pic. Need metering to remain fluid.  2. I focus. Move the camera to change the framing. Keep the focus. Have the metering update.  

And, yes, under both of these I can use the BBs, but I don't want to have to.

BTW, I lived in Wellesley for 17 years.

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I believe the metering will update any time you press the shutter, irregardless of shooting mode.  I still say the One Shot mode, which is the default behavior as Bob observed, should do what you want.  This what you can do for your above scenarios.

1.  In One Shot mode, the camera focuses when you half press the shutter, and will maintain a focus lock for as long as you maintain the shutter button half pressed.  Depending upon the mode, the exposure will stay locked, or will dynamically any one of the three legs of the exposure triangle.

2.  See #1, and the following.  Use P mode to lock the exposure.  Use Av mode to allow the camera to update exposure by adjusting shutter speed.  Use Tv mode to allow the camera to adjust exposure by adjusting shutter speed.  Use M mode with ISO set to AUTO to allow the camera to adjust exposure by adjusting the ISO settings.

If you do not wish to use BBF, then you will have to hold the shutter half pressed until you want to take the shot.  I guess that I do not fully understand your issue.  It seems to me that the factory default behavior does what you want.  Either hold the shutter half pressed, or use Back Button Focus.

[manatee4mation]

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@Waddizzle wrote:

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@manatee4mation wrote:

A number of scenarios. Here are a couple. 1. I set up a shot. Shallow focus. Non-studio setting. Natural light. I get just the right focus. I want something interesting to happen. A butterfly enter the scene, for example. The moment that happens. Snap the pic. Need metering to remain fluid.  2. I focus. Move the camera to change the framing. Keep the focus. Have the metering update.  

And, yes, under both of these I can use the BBs, but I don't want to have to.

BTW, I lived in Wellesley for 17 years.

---

I believe the metering will update any time you press the shutter, irregardless of shooting mode.  I still say the One Shot mode, which is the default behavior as Bob observed, should do what you want.  This what you can do for your above scenarios.

1.  In One Shot mode, the camera focuses when you half press the shutter, and will maintain a focus lock for as long as you maintain the shutter button half pressed.  Depending upon the mode, the exposure will stay locked, or will dynamically any one of the three legs of the exposure triangle.

2.  See #1, and the following.  Use P mode to lock the exposure.  Use Av mode to allow the camera to update exposure by adjusting shutter speed.  Use Tv mode to allow the camera to adjust exposure by adjusting shutter speed.  Use M mode with ISO set to AUTO to allow the camera to adjust exposure by adjusting the ISO settings.

If you do not wish to use BBF, then you will have to hold the shutter half pressed until you want to take the shot.  I guess that I do not fully understand your issue.  It seems to me that the factory default behavior does what you want.  Either hold the shutter half pressed, or use Back Button Focus.

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Your conclusions are not correct. The only leg of the triangle that is dynamic is the ISO in ISO auto mode. Aperture and shutter speed are static once you half-press the shutter.  Canon confirmed this in a call I had with them today.

If you have a Canon DSLR this is really easy to test. I just replied to Bob and you can see the easy test I posted.

If you have a Nikon or Sony you will see the default behavior you describe.

[manatee4mation]

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@Waddizzle wrote:

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@manatee4mation wrote:

A number of scenarios. Here are a couple. 1. I set up a shot. Shallow focus. Non-studio setting. Natural light. I get just the right focus. I want something interesting to happen. A butterfly enter the scene, for example. The moment that happens. Snap the pic. Need metering to remain fluid.  2. I focus. Move the camera to change the framing. Keep the focus. Have the metering update.  

And, yes, under both of these I can use the BBs, but I don't want to have to.

BTW, I lived in Wellesley for 17 years.

---

I believe the metering will update any time you press the shutter, irregardless of shooting mode.  I still say the One Shot mode, which is the default behavior as Bob observed, should do what you want.  This what you can do for your above scenarios.

1.  In One Shot mode, the camera focuses when you half press the shutter, and will maintain a focus lock for as long as you maintain the shutter button half pressed.  Depending upon the mode, the exposure will stay locked, or will dynamically any one of the three legs of the exposure triangle.

2.  See #1, and the following.  Use P mode to lock the exposure.  Use Av mode to allow the camera to update exposure by adjusting shutter speed.  Use Tv mode to allow the camera to adjust exposure by adjusting shutter speed.  Use M mode with ISO set to AUTO to allow the camera to adjust exposure by adjusting the ISO settings.

If you do not wish to use BBF, then you will have to hold the shutter half pressed until you want to take the shot.  I guess that I do not fully understand your issue.  It seems to me that the factory default behavior does what you want.  Either hold the shutter half pressed, or use Back Button Focus.

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If you have any Canon DSLR you can see that you are not correct. Press the shutter half way and hold in in P, AV, or TV and the meter is locked into that exposure. Period. Move the camera. Point it at the sun. The original exposure is locked.

In M, if you have auto ISO, the ISO will change with the shutter half-pressed. If you do not auto-ISO, the exposure comp will change.

[TCampbell]

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@manatee4mation wrote:

If you have any Canon DSLR you can see that you are not correct. Press the shutter half way and hold in in P, AV, or TV and the meter is locked into that exposure. Period. Move the camera. Point it at the sun. The original exposure is locked.

In M, if you have auto ISO, the ISO will change with the shutter half-pressed. If you do not auto-ISO, the exposure comp will change.

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Hi Manatee4mation,

You may want to reset your camera to factory defaults.  The above statement is not correct.  A Canon EOS camera will (by default) continously update the metering as you continue to hold the shutter button and move the camera.

If you are not seeing it update the metering continuously as you half-press the button and move the camera to areas with different lighting, then something has been changed on your camera. 

You can lock the metering by pressing the AE Lock button (by default it's the asterisk on the back of the camera but it can be re-assigned) and if you do this, THEN the metering will lock in and re-composing the shot will not update the exposure.  The 5D IV has two modes for this.... the default version of AE Lock only locks until you take a shot (or until you let the camera metering system switch off (e.g. if you are looking through the viewfinder and the digital metering & shooting info goes dark... that clears an AE Lock.)  The other version is an AE Lock + Hold.  That version (the "Hold") maintains the exposure lock until you cancel it... or refresh it with new metering... or until you switch off the camera.