Exposure Lock questions

[balex78]

Hi I've bought Steve's 3 books about BIF photography, Nikon AF settings and Exposure.

My Gear is : Nikon D500 + 200-500mm F5.6

There's 4 things I didn't quite catch about exposure lock

1) Do I have to be in spot metering mode to lock the exposure?

2) Do I have to choose a fixed ISO value or can I be in AUTO ISO? with a fixed ISO value , how can I be sure about the correct exposure?

3) Do I have to keep the button pressed (Fn1 for me) to lock the exposure, then point the camera to my subject with the button still pressed and simultaneously keep the autofocus button pressed (back button AF-ON) to focus on the subject and then shoot? All with the two buttons still pressed?

4) After shooting, do I have to repeat all the steps or does the exposure remain memorized?

Thanks a lot!

 

[jeffnles1]

Hi I've bought Steve's 3 books about BIF photography, Nikon AF settings and Exposure.

My Gear is : Nikon D500 + 200-500mm F5.6
(I shoot the same model and lens combo)
There's 4 things I didn't quite catch about exposure lock

1) Do I have to be in spot metering mode to lock the exposure?
(No. It should work in Matrix or any of the other modes).

2) Do I have to choose a fixed ISO value or can I be in AUTO ISO? with a fixed ISO value , how can I be sure about the correct exposure?
(Good question. I never gave this one much thought and my camera is not near. I think it locks the exposure which would be the same with auto ISO but I cannot say for sure. Easy enough to test. Focus and meter on something, press and hold whatever button you have set for AE Lock and take a couple photos of things of different brightness with the lock button still held down. See if your ISO changes in the metadata.)

3) Do I have to keep the button pressed (Fn1 for me) to lock the exposure, then point the camera to my subject with the button still pressed and simultaneously keep the autofocus button pressed (back button AF-ON) to focus on the subject and then shoot? All with the two buttons still pressed?
(Yes. A 6th finger on each hand would be a bonus.. )

4) After shooting, do I have to repeat all the steps or does the exposure remain memorized?
(Once you release the button, it goes back to whatever you had set before.)

(I rarely use AE lock. When I want to lock in an exposure, I turn auto iso off. I'll set exposure on something close to middle gray like a tree trunk and lock the ISO at whatever point the meter says. Then I can adjust shutter speed or aperture up or down to my liking. Honestly, I use the Exposure Compensation button a whole lot more dialing + or - values to get the desired effect. One of the main reasons I use auto iso is because out in nature if I'm following an animal or bird with the lens, the light changes so rapidly as it moves from shade to sun to diffused light the camera's computer can keep up a lot faster than my brain. I use AF Lock more - I do not use back button focus. I tried it for about 18 months and never got totally comfortable with it. The finger dance of buttons between the back button to focus and others, (the shutter button to release the shutter, and the other custom buttons I have like PV to engage spot meter and FN1 to activate group AF) reminded me of piano lessons.)

Thanks a lot!

 

[balex78]

thanks a lot! The location where I go shooting is kind of a mess...the background changes continuously...and so does its brightness...trees, bushes, cement, water, buildings, grass, sky portions...so exposure lock might do the trick there...but I gotta learn how to do it correctly. Perhaps I have to be in full manual, correct the iso value until the meter is right on the middle and then lock it and shoot my subjects?? while I execute the locking procedure I could take a look at iso value the camera shows with the meter in the middle and use that value for all the shooting I make that day at that place?

 

[tclune]

The D500 manual discusses this on pages 141 and 142. It says that AE-Lock applies to center-weighted and spot metering. It also indicates that, while AE-Lock is active, an AE-Lock indicator will appear in the viewfinder. I don't use AE-Lock myself, but those two points seem like pretty good clues for getting familiar with it. FWIW

 

[bleirer]

You might also check in your manual whether you can set it as a toggle or just a hold. I know on my Canon I have a choice. I find the toggle better because once pressed I can remove my thumb and the exposure stays locked until I hit the button to unlock.

 

[NorthernFocus]

thanks a lot! The location where I go shooting is kind of a mess...the background changes continuously...and so does its brightness...trees, bushes, cement, water, buildings, grass, sky portions...so exposure lock might do the trick there...but I gotta learn how to do it correctly. Perhaps I have to be in full manual, correct the iso value until the meter is right on the middle and then lock it and shoot my subjects?? while I execute the locking procedure I could take a look at iso value the camera shows with the meter in the middle and use that value for all the shooting I make that day at that place?

Shooting BIF it's fairly normal to have to deal with BG that changes dramatically as you track the bird. The simple solution is to shoot in fully manual mode, including ISO. For BIF having ss, and f-stop in manual is a no brainer. You want ss locked down to stop the motion and more often than not want aperture wide open. So ISO really becomes the only variable. Pick an exposure that will properly expose the bird and don't worry about the BG. Many times you can't have both properly exposed so get the subject right and deal with the BG as best you can with PP. Or not. If you're familiar with the "sunny 16 rule" it works great on clear days. In the end you have to find what works for you.

 

[EricBowles]

Perhaps I have to be in full manual, correct the iso value until the meter is right on the middle and then lock it and shoot my subjects?? while I execute the locking procedure I could take a look at iso value the camera shows with the meter in the middle and use that value for all the shooting I make that day at that place?

This is probably the easiest approach. If the light on your subject is not changing, all exposure settings would be unchanged regardless of what is happening with the "trees, bushes, cement, water, etc."

With manual exposure mode there is nothing that says the indicator needs to be right in the middle. The middle is subject to metering, Exposure Comp, and each specific composition. The indicator might be useful if you have slight changes in light level for the same composition, in which case you could adjust exposure settings slightly to return the indicator to the original position. But the exactly position of the indicator does not matter and should not be viewed as something you need to move to the middle. Remember - exposure compensation does not change your exposure in full manual mode - it just changes the position of the indicator.

If you are in full manual, and the lighting on the subject suddenly changes or you see a different subject with different lighting, just flip to Auto ISO. You will quickly be close to the correct exposure and can use Exposure Comp. I often set up Manual mode for full sun, and Exposure Comp with any ISO mode for full or partial shade. If my subject is a small bird in full sun, I use Manual, but when I quickly have a subject in full or partial shade, I just switch to Auto ISO with a little Exp Comp already set.