[Bui]

Recently I started experimenting with back-button focus on my KP. In button customization menu I set the value of AE/AL to AF2 (only AE/AL can be used to focus). The result has been ok and I started feeling the benefit of this method, minus this issue:

Before, using shutter to focus, if the camera is idle (not being touch after some minutes), if I need to take a photo, I can simply half press the shutter, and the camera would “wake up” and then focus immediately. Now, with focusing action assigned sorely to AE/AL, if the camera is idle, I have to press shutter to wake it up, then press AE/AL to focus, as the camera doesn’t respond on pressing AE/AL alone. This doesn’t take a lot of time but is quite annoying.

Maybe I’m missing something with the setup, do you have an idea?

Thanks.

[pepperberry farm]

I use bbf on both of my K-3's, but I use the AF button...

I have the same behavior with both bodies, but find it less annoying...

[rogerstg]

Maybe I’m missing something with the setup, do you have an idea?

You're not missing anything, it's the same on my KP: the method of waking it doesn't change with back button focus. Lucky for me that I don't find it annoying.

[clackers]

The shutter button still wakes up the camera and takes the picture, the BB just does the focusing now.

[stevebrot]

Now, with focusing action assigned sorely to AE/AL, if the camera is idle, I have to press shutter to wake it up, then press AE/AL to focus, as the camera doesn’t respond on pressing AE/AL alone. This doesn’t take a lot of time but is quite annoying.

That is what you configured. Sorry it comes with the penalty of having to use the buttons according to set up. You might be able to use the AE/AL button to wake the camera up, if that seems more natural.

Edit: Various buttons will wake the meter and/or camera. Which ones work for what depends on model.


Steve

[shadowjester]

So if it is possible, how can you configure the camera to wake up on BBF and/or Green button press?

[tljensen]

I tried back button focus on my KP for a few months but never really warmed up to it. Instead I reprogrammed it for back button exposure lock. For me, that's more usable. If there is an area that is getting blown out, like the light area of a cloud, then I simply point to the blown out area, hit the back button, then go back to the subject. An other use is to set the exposure on the subject then move the camera so the subject is not in the center of the image. Hitting the back AE button presents a "star" in the view finder so you know when it has locked exposure. Hit it again and the camera returns to normal. Both my KP and D750 are now set up this way and I find it much more useful than back button focus.

[stevebrot]

So if it is possible, how can you configure the camera to wake up on BBF and/or Green button press?

I need to edit my comment. Other buttons may be used to wake camera/meter. Which one's work depends on camera model.


Steve

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Last edited by stevebrot; 05-15-2019 at 02:10 PM.

[TerryL]

The benefits of using BB focus are great. I love it and wouldn't change it.

[ubjy]

I wish I could use the green button for back button AF as I have to adjust my grip to reach ae button

[Bui]

Dig my old thread up, because I've been finding the limitation even more annoying, as I missed a lot of candid moments, just because, when I realized those, I put my camera on, then I have to press shutter button to wake the camera up, then switch to AE/AL to focus, sometimes I forgot that and pressed the AE/AL directly, only to realized I have to wake it up first. All of these steps cost me 1-2 valuable seconds, not to mention the KP+20-40 combination is quite slow to focus (my experience, I never handle non-Pentax camera), and the moment was gone :-) I wish to be able to wake up and focus on the same button, and aside from going back to shutter button, is it even possible?

My issue with focusing using shutter button, the reason why I switched to back-button focus and completely disabled shutter focus, is when I pre-focus for a scene, and re-compose, or doing group/family shots, the camera would try to focus again when I press it to take photos, and I think you all know this issue very well.

[JensE]

My issue with focusing using shutter button, the reason why I switched to back-button focus and completely disabled shutter focus, is when I pre-focus for a scene, and re-compose, or doing group/family shots, the camera would try to focus again when I press it to take photos, and I think you all know this issue very well.

One solution is to set the AF-button to disable focusing and hold it when recomposing a photo, and e.g. set Fx1 to do AE-L.

[Breakfastographer]

Bui, did you follow the last step of the procedure described here:
Set up back button focus on a Pentax DSLR – breakfastographer

Hope this helps.

[Larrymc]

Always make the shutter button "tap" part of your routine prior to pushing the A/F button for BBF. I do that now and lose very little time and it has become second nature when holding or picking up my K-3. That way there is never a problem.