Autofocus / Autoexposure Question

**Larrymc** · 12-21-2015, 05:06 AM

Hi Folks

There are a couple of options in my Pentax K-3 custom menu that I have been confused about for a long time andafter a recent discussion about BBF got me wondering and confused again after a year of use. The options are AE-L with AF Locked and Link AE and AF Point. What are the conditions where you would want each option on and or each option off or one or the other either on or off. Using BBF and AF Single then locking focus and then recomposing would it be better to decouple both options rather than coupling them. I can see a situation when using BBF and locking focus, AE-L would probably not be working in the first place. What are everyone's thoughts on this? The Manual isn't a ton of help on this at all

Larry

blende8 · 12-21-2015, 06:19 AM

Link AE and AF Point is useful when you use a non centered AF point.
This area is weighted stronger then for exposure.

AE-L with AF Locked
I haven't found a useful application for this feature yet.

**Larrymc** · 12-21-2015, 06:49 AM

Originally posted by blende8

Link AE and AF Point is useful when you use a non centered AF point.
This area is weighted stronger then for exposure.

AE-L with AF Locked
I haven't found a useful application for this feature yet.

Linking AE point with AF point, thats what I assumed. I use Back button Auto focus and I haven't quite decided if this option totally decouples the shutter button for autoexposure purposes and couples it to the AF button on the back of the K-3 when the camera is setup to decouple the shutter button from focus.

Larry

pathdoc · 12-21-2015, 07:00 AM

Originally posted by blende8

AE-L with AF Locked
I haven't found a useful application for this feature yet.

"Focus, meter, recompose, shoot." Useful with metering in spot mode, especially if you're using MF lenses or third-party AF lenses that don't communicate fully with the camera body, multi-point functions are disabled, and light conditions are complex and might confuse a centre-weighted or matrix picture. I use a lot of older and MF glass on my K-5, so I have this option turned on and use the AF in its focus-confirm incarnation.

**Larrymc** · 12-21-2015, 07:13 AM

Originally posted by pathdoc

"Focus, meter, recompose, shoot." Useful with metering in spot mode, especially if you're using MF lenses or third-party AF lenses that don't communicate fully with the camera body, multi-point functions are disabled, and light conditions are complex and might confuse a centre-weighted or matrix picture. I use a lot of older and MF glass on my K-5, so I have this option turned on and use the AF in its focus-confirm incarnation.

So if one is using Back button auto focus is the Auto exposure locked when Auto focus is locked? If so, this would relegate the shutter button to only release the shutter when desired, would it not? This would make the shutter button react like a manual only film camera.

Larry

pathdoc · 12-21-2015, 07:25 AM

I can't really say. I've tried back button AF and it never really worked for me, so I gave up.

IchabodCrane · 12-21-2015, 07:50 AM

Originally posted by Larrymc

So if one is using Back button auto focus is the Auto exposure locked when Auto focus is locked? If so, this would relegate the shutter button to only release the shutter when desired, would it not? This would make the shutter button react like a manual only film camera.

Larry

For simplicity, I'm assuming you're using BBF with AF-S and not AF-C. When you have AE-L with AF Locked set as "on", then when you press the AF button and the camera "beeps" to lock focus, then the exposure will be locked as long as you continue to hold down the AF button. You'll notice this to be the case as the little star on the button of the viewfinder (indicating locked exposure) will stay on until you release the AF button. With it set to "off", the exposure continues to adjust as you move around the camera regardless of whether you hold down the AF button or not.

Hope this helps!

blende8 · 12-21-2015, 08:11 AM

Originally posted by pathdoc

"Focus, meter, recompose, shoot."

Well, I use the AE-L button for that.
Do you really fiddle in the menu for rare cases like that?

**Larrymc** · 12-21-2015, 08:47 AM

Originally posted by IchabodCrane

For simplicity, I'm assuming you're using BBF with AF-S and not AF-C. When you have AE-L with AF Locked set as "on", then when you press the AF button and the camera "beeps" to lock focus, then the exposure will be locked as long as you continue to hold down the AF button. You'll notice this to be the case as the little star on the button of the viewfinder (indicating locked exposure) will stay on until you release the AF button. With it set to "off", the exposure continues to adjust as you move around the camera regardless of whether you hold down the AF button or not.

Hope this helps!

Hmmmm, I use BBF in both AF-S and AF-C so I think my best bet is to turn that feature off and use the shutter button for AE. Lately I have been staying in AF-C and holding it down for continuous focus and releasing it for non-continuous focus. Thanks

Larry

IchabodCrane · 12-21-2015, 09:06 AM

Originally posted by Larrymc

Hmmmm, I use BBF in both AF-S and AF-C so I think my best bet is to turn that feature off and use the shutter button for AE. Lately I have been staying in AF-C and holding it down for continuous focus and releasing it for non-continuous focus. Thanks

Larry

Yes, I haven't seen a use for the "lock" option when using BBF in conjunction with AF-C (which is what I do, too). But we still have the separate AE-L button which can accomplish the same thing if needed.

12-21-2015, 05:06 AM	#1
Larrymc Site Supporter Join Date: Jun 2014 Location: Mississippi, USA Posts: 5,252	Autofocus / Autoexposure Question Hi Folks There are a couple of options in my Pentax K-3 custom menu that I have been confused about for a long time andafter a recent discussion about BBF got me wondering and confused again after a year of use. The options are AE-L with AF Locked and Link AE and AF Point. What are the conditions where you would want each option on and or each option off or one or the other either on or off. Using BBF and AF Single then locking focus and then recomposing would it be better to decouple both options rather than coupling them. I can see a situation when using BBF and locking focus, AE-L would probably not be working in the first place. What are everyone's thoughts on this? The Manual isn't a ton of help on this at all Larry

12-21-2015, 08:47 AM	#9
Larrymc Site Supporter Join Date: Jun 2014 Location: Mississippi, USA Posts: 5,252 Original Poster	Originally posted by IchabodCrane For simplicity, I'm assuming you're using BBF with AF-S and not AF-C. When you have AE-L with AF Locked set as "on", then when you press the AF button and the camera "beeps" to lock focus, then the exposure will be locked as long as you continue to hold down the AF button. You'll notice this to be the case as the little star on the button of the viewfinder (indicating locked exposure) will stay on until you release the AF button. With it set to "off", the exposure continues to adjust as you move around the camera regardless of whether you hold down the AF button or not. Hope this helps! Hmmmm, I use BBF in both AF-S and AF-C so I think my best bet is to turn that feature off and use the shutter button for AE. Lately I have been staying in AF-C and holding it down for continuous focus and releasing it for non-continuous focus. Thanks Larry Last edited by Larrymc; 12-21-2015 at 08:52 AM.

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12-21-2015, 06:19 AM	#2
blende8 Veteran Member Join Date: Feb 2007 Location: Bremen, Germany Photos: Albums Posts: 1,521	Link AE and AF Point is useful when you use a non centered AF point. This area is weighted stronger then for exposure. AE-L with AF Locked I haven't found a useful application for this feature yet.

12-21-2015, 06:49 AM	#3
Larrymc Site Supporter Join Date: Jun 2014 Location: Mississippi, USA Posts: 5,252 Original Poster	Originally posted by blende8 Link AE and AF Point is useful when you use a non centered AF point. This area is weighted stronger then for exposure. AE-L with AF Locked I haven't found a useful application for this feature yet. Linking AE point with AF point, thats what I assumed. I use Back button Auto focus and I haven't quite decided if this option totally decouples the shutter button for autoexposure purposes and couples it to the AF button on the back of the K-3 when the camera is setup to decouple the shutter button from focus. Larry

12-21-2015, 07:00 AM	#4
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	Originally posted by blende8 AE-L with AF Locked I haven't found a useful application for this feature yet. "Focus, meter, recompose, shoot." Useful with metering in spot mode, especially if you're using MF lenses or third-party AF lenses that don't communicate fully with the camera body, multi-point functions are disabled, and light conditions are complex and might confuse a centre-weighted or matrix picture. I use a lot of older and MF glass on my K-5, so I have this option turned on and use the AF in its focus-confirm incarnation.

12-21-2015, 07:13 AM	#5
Larrymc Site Supporter Join Date: Jun 2014 Location: Mississippi, USA Posts: 5,252 Original Poster	Originally posted by pathdoc "Focus, meter, recompose, shoot." Useful with metering in spot mode, especially if you're using MF lenses or third-party AF lenses that don't communicate fully with the camera body, multi-point functions are disabled, and light conditions are complex and might confuse a centre-weighted or matrix picture. I use a lot of older and MF glass on my K-5, so I have this option turned on and use the AF in its focus-confirm incarnation. So if one is using Back button auto focus is the Auto exposure locked when Auto focus is locked? If so, this would relegate the shutter button to only release the shutter when desired, would it not? This would make the shutter button react like a manual only film camera. Larry

12-21-2015, 07:25 AM	#6
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	I can't really say. I've tried back button AF and it never really worked for me, so I gave up.

12-21-2015, 07:50 AM	#7
IchabodCrane Veteran Member Join Date: Sep 2012 Photos: Gallery \| Albums Posts: 1,728	Originally posted by Larrymc So if one is using Back button auto focus is the Auto exposure locked when Auto focus is locked? If so, this would relegate the shutter button to only release the shutter when desired, would it not? This would make the shutter button react like a manual only film camera. Larry For simplicity, I'm assuming you're using BBF with AF-S and not AF-C. When you have AE-L with AF Locked set as "on", then when you press the AF button and the camera "beeps" to lock focus, then the exposure will be locked as long as you continue to hold down the AF button. You'll notice this to be the case as the little star on the button of the viewfinder (indicating locked exposure) will stay on until you release the AF button. With it set to "off", the exposure continues to adjust as you move around the camera regardless of whether you hold down the AF button or not. Hope this helps!

12-21-2015, 08:11 AM	#8
blende8 Veteran Member Join Date: Feb 2007 Location: Bremen, Germany Photos: Albums Posts: 1,521	Originally posted by pathdoc "Focus, meter, recompose, shoot." Well, I use the AE-L button for that. Do you really fiddle in the menu for rare cases like that?

12-21-2015, 09:06 AM	#10
IchabodCrane Veteran Member Join Date: Sep 2012 Photos: Gallery \| Albums Posts: 1,728	Originally posted by Larrymc Hmmmm, I use BBF in both AF-S and AF-C so I think my best bet is to turn that feature off and use the shutter button for AE. Lately I have been staying in AF-C and holding it down for continuous focus and releasing it for non-continuous focus. Thanks Larry Yes, I haven't seen a use for the "lock" option when using BBF in conjunction with AF-C (which is what I do, too). But we still have the separate AE-L button which can accomplish the same thing if needed.