Program EOS 70D to hold exposure

[moonlight33]

On the Canon EOS 70D, there is a button one can press to hold the exposure and then reframe the shot. It is unbearably difficult, because often I need to hold the focal point as well and it is hard not to accidentally press the shutter, etc.  When I utilized a Canon film camera, I could use the focal point to hold the focus AND the exposure point together by simply pressing the shutter halfway, then re-framing.  Please can someone help me to find a way to program this camera to always sync the exposure with the focal point so I do not have to press the little button (which is hard to not mess up due to there being 2 other little buttons in the same area)? Thank you so much, this is how I shoot all of my shots, it is not possible to work quickly without a way to program this.

[Waddizzle]

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@moonlight33 wrote:

I am in need of #3. I wish to use partial metering most often (and periodically spot metering). I choose the focal/metering point simultaneously and then reframe and shoot.  I do not re-focus.  I need one step only. Thanks!

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With the exception of Evaluative Metering, every metering mode meters from the center of the screen.  The difference from one mode to the next is the size of the metered area and how much “weight” is given to this area.

The default Evaluative Metering mode behavior for the camera when set to One Shot AF mode and 1 pt AF is to biased the exposure at the locked AF point.

If your backgrounds are not bright or dark enough to your satisfaction, then that could be an entirely different issue.  And, this strategy that you aare employing to correct the issue is not getting the job done.

I mentioned in an earlier post that you may need to use post processing of the images to achieve the final result that you want.  The camera has limited dynamic range when it comes its light gathering ability.  

If I knew more about what exactly you are trying to photograph, then I might be able to offer more insight and suggestions to you.

[moonlight33]

Thank you again to everyone for the replies.  I double checked my camera settings to make sure I was using what you are suggesting, the One Shot AF mode & 1-pt auto focus. My need is to use these modes along with PARTIAL METERING (or possibly spot metering).  I need these metering options.  I need a one-step process, as I used to do with film photography.  I choose the spot I wish to focus and simultaneously the same exact spot sets my exposure in AV mode.  I then reframe and shoot and refocus/meter as I move around with my subject.  This is what I am in need of for professional work.  I cannot toy around with the little buttons, it doesn't work for me for many reasons.  This is so frustrating.  I do not wish to use evaluative metering and then work on the image in post-production.  I am used to a certain workflow.  Thank you if anyone knows how to accomplish this! Thank you!

[Anonymous]

Do you still have to press the back button and the shutter to take a photo? If so, you don't have your shutter button half press function reset to default. When set to AF start and Metering start, you will only have to press the shutter to take a photo, no other buttons will need to be used. Is this what you are trying to accomplish?

[moonlight33]

Hello, I press halfway which sets the focus and exposure, however, I keep it pressed halfway and then reframe but it will not hold the exposure unless I press the little back button. Unless I am in evaluative. I wish to use partial or spot or center, etc.  Those modes will not hold the exposure without a second step. Thanks, trying to find a way to program this.

[Anonymous]

Double check your shutter button programming to make sure AF start and Metering start are assigned to the shutter button half press.

[jrhoffman75]

That’s only available with the 1D series:

[stevet1]

Moonlight123,

Here is one way to accomplish your goal, I think:

1) Go to your menu settings and re-assign your focus to the AF-On button. Also assign your exposure lock to the *  button.

2) Make sure you are in Single.Shot, not AI Servo.

3) Aim your camera at the spot you want to expose for and half-press your shutter button. This will meter the exposure for you and tell you the settings.

4) Press your little * button to lock that exposure.

5) Press and hold down the AF-On button and don't let go.

6) Re-compose your shot and take your picture.

7) As John mentioned on the first page of this Thread, the * button, or AE lock, only locks your exposure for about 4 seconds. It doesn't hold that lock. There are two buttons that I am aware of that will hold that lock. One is the AF-On button, and the other is the little Depth of Field Preview button on the bottom of your camera.

If you meter the part of the scene you want to expose for, lock that metering wiith the AE lock *  button, and then hit and hold down the AF-ON button, you can focus on that spot. As long as you are in Single Shot and not Servo, the Camera will not focus again as long as you don't let go, and you can hold that metering for as long as you like. You can take your time re-composing your shot.

Steve Thomas

[Waddizzle]

“ Thank you again to everyone for the replies.  I double checked my camera settings to make sure I was using what you are suggesting, the One Shot AF mode & 1-pt auto focus. My need is to use these modes along with PARTIAL METERING (or possibly spot metering).  I need these metering options.  I need a one-step process, as I used to do with film photography.  I choose the spot I wish to focus and simultaneously the same exact spot sets my exposure in AV mode.  I then reframe and shoot and refocus/meter as I move around with my subject.  This is what I am in need of for professional work.  I cannot toy around with the little buttons, it doesn't work for me for many reasons.  This is so frustrating.  I do not wish to use evaluative metering and then work on the image in post-production.  I am used to a certain workflow.  Thank you if anyone knows how to accomplish this! Thank you! “

As I have pointed out earlier, One Shot AF mode locks exposure when it locks focus.  You half-press the shutter to lock focus, and you will need to maintain the half press to maintain the focus and exposure lock.

Evaluative Metering can bind exposure to any AF point.  All the other metering modes bind exposure to the center AF point.  The primary difference is the size of the metered area.

You can use Partial Metering, if you wish.   You will be restricted to only using the center AF Point. As long as you use One Shot AF and maintain the half press on the Shutter Button, you should not need to use the [AE Lock] button, at all.

[moonlight33]

Thank you so much for the reply again.  The problem is that I need to reframe the shot without losing my exposure. I can only find a way to do this while utilizing Evaluative, but have been searching for a solution to program the camera to use partial or spot, etc. metering without having to press a second button over and over. I need a one step process to lock the exposure while I reframe.  Thanks!

[Waddizzle]

Use only the center AF point with One Shot AF and any metering mode you wish.  The exposure gets locked when the focus is locked.

https://youtu.be/wKA92h0MfIE?si=SI7GTmsnLSFEElPP 

With Evaluative Metering, you can use any AF point to lock focus and bind the exposure to it.  This was in the article that I posted a link to on page 1