[Mike.P®]

I have it set to centre focus as I have my focus set to SEL and its a quick way of getting it back to where I normally want it.

I would rather have it enabled to actually change from auto to manual focus though instead of having that switch round the front which is a pain.

[Kerrowdown]

I've only got manual lenses (apart from kit that came with body) so................................................................................buttons no good for me.

[Ratmagiclady]

I was thinking I might configure it so a half-press of the shutter is AE-L and use the AE-L button for focus. Is that possible? (Should find out in a few days)

[hinckc]

I currently use the AF button, but only after de-coupling AF from the shutter button.
It took some getting used to, but I would never go back to shutter button AF, if I could avoid it.

I use:
P mode
AF-C
AF-button for AF
AF point SEL

Setup like this, I can compose, focus, adjust exposure, then shoot, in four discreet steps, and without lifting my eye from the viewfinder. It focuses when I tell it, and it doesn't stop until I tell it to stop. When I press the shutter button, it never hesitates a second...

Thanks a ton to the people on the forum who've advocated it! It has really improved how happy I am with my results.

Funny thing... I usually find myself thinking in terms of EV compensation for the shot I've framed, rather than using AE-L, so my AE-L button goes unused. When I would think in terms of AE-L, I'm usually using Manual mode.

-Chris

[Ratmagiclady]

Funny thing... I usually find myself thinking in terms of EV compensation for the shot I've framed, rather than using AE-L, so my AE-L button goes unused. When I would think in terms of AE-L, I'm usually using Manual mode.

-Chris

I usually use manual in general: using an AE-L at the shutter button is kind of a habit I picked up from the bridge camera I have been using: lacking control wheels, it's always been just easier to grab the light reading I want somewhere in sight and recompose. I'm thinking it might be quicker when using non-A lenses in Av mode, as well. It seems the shutter half-press is a place where I could have that function where it'd otherwise not be in the way.

All theory at this point.

[ratjadi]

I have turned off focusing on shutter half press and use the AF button to make the camera focus. This way, there is a button for picture taking, and another button for autofocusing. That way as i'm firing off shots, I don't have to worry about acidently causing the camera to refocus on something else and maybe losing a shot. I also remember times where the camera trying to refocus caused it to not take the picture even when I press the shutter button all the way. Having the two actions on seperate buttons solves that problem also. I would sudjest trying it this way and seeing if you lilke it or not. I origionally tried cause I had heard it's the way many "pros" did it, but once I started, I never looked back.

I couldn't have described it any better!

[soccerjoe5]

I use the AF button to disengage autofocus, for instant manual focus.

[vitalsax]

i use the af botton pressing it all the time when i'm using af-c then take the shot whenever i want.

[res3567]

After reading all of the psts on this thread and going to the Canon link I just tried on my K10D. It will take some getting used to, especially with the grip, but I can clearly see the advantages in certain situations. AF button enabled to set autofocus. Shutter button by press halfway to autofocus off. And, as the Canon link explains, you can always set the camera back to default.

[Ratmagiclady]

I use the AF button to disengage autofocus, for instant manual focus.

Oooh, you get MF that way? Sold!

[heliphoto]

Oooh, you get MF that way? Sold!

You do - if you're using a lens which has a quick-shift type mechanism like most of the DA line, and the HSM Sigma's (50-150 and 70-200 have this feature I think). With a normally geared AF lens you still have to flip the switch to MF or press the lens release button if you're into that trick - otherwise the gear train's still engaged.

[allill]

I wish I read this thread sooner, I shot a bunch of pictures in the dark last night and my K10D had some hesitation. I didn't want to shoot MF and this would've been a great option.

[Ratmagiclady]

You do - if you're using a lens which has a quick-shift type mechanism like most of the DA line, and the HSM Sigma's (50-150 and 70-200 have this feature I think). With a normally geared AF lens you still have to flip the switch to MF or press the lens release button if you're into that trick - otherwise the gear train's still engaged.

Aww. Well, that's not so much help, then. Switch it'll probably be. Ideal would be an AF that'd just hand off focusing when I took the ring, until I pressed whatever activates AF again.

I'm not too worried about the switch being a pain. anyway, if you can't have it right in the mechanism. I'm an expert lever-puller.

[PDL]

I don't want to taint this poll, but I have read and re-read the owners manual on this, and cannot think of one good reason to ever use this.

So if you use it, please provide a description and tell me why it isn't a White Balance button which I would use ALL OF THE TIME.

Here is a list of threads and a few quotes about using the AF/OK button(s) instead of depending on the stupid shutter button to trigger AF:

https://www.pentaxforums.com/forums/general-pentax-photography/42355-10-autofocus-tips.html
https://www.pentaxforums.com/forums/pentax-dslr-discussion/12191-k10-autofocus-question.html
https://www.pentaxforums.com/forums/pentax-dslr-discussion/4585-auto-focus-how-do-you-use-3.html
https://www.pentaxforums.com/forums/everything-else/8754-talk-me-out-selling-...ntax-gear.html
https://www.pentaxforums.com/forums/pentax-dslr-discussion/38910-focus-lock-subject.html
https://www.pentaxforums.com/forums/pentax-dslr-discussion/36253-if-you-cant-...ur-pentax.html
https://www.pentaxforums.com/forums/general-pentax-photography/29112-2-questions.html
https://www.pentaxforums.com/forums/general-pentax-photography/22603-manual-f...yperfocal.html
https://www.pentaxforums.com/forums/pentax-dslr-discussion/19093-do-you-use-af-button-3.html
Quote from the above thread
The use of the AF button and the de-coupling of AF from the shutter button allows me to usd my DSLR's just like I did my manual cameras.

Manual SLR:
See something to shoot. Put camera up to eye (no buttons pushed). Decide on what to focus -Focus. Look at scene - sometimes after taking the camera away from my eye), find object to meter off of. Look through VF and set exposure (old one was a match needle - LED's acutally - not a Pentax). Compose image - refocus as necessary. Make the exposure.

DSLR:
See something to shoot. Put camera up to eye (tap shutter button to power on). Decide on what to focus and push AF button (using center AF). Look at scene - sometimes after taking the camera away from my eye), find object to meter off of. Look through VF and set exposure (AE-L). Compose image - refocus as necessary (using AF button or manually turning the focus ring - no need to switch anything off or on). Make the exposure.

Now this is just my way of doing things - no better or no worse than keeping everything auto all the time. I find myself locking the exposure - then deciding that the exposure is not really right or I just do not like the shutter speed or f:stop (I use AV 99.999%). All I have to do is release the shutter button - then find the "object" that I wish to meter off of - recompose and shoot. Now if I did that with AF coupled to the shutter button --- and here is the key ---- the CAMERA starts to look for something to focus on --- not ME.

As for using left/right eye - do whatever you need to do - I am right eyed and I find my nose hitting the Menu or Info button - Oh for old manual cameras with no buttons on the back at all - simplicity, what is wrong with that? Now what ever you do with the AF button - or OK button on the *ist Ds - is just fine with me. I just prefer to be in control - with all the fuss about "AF is slow and s*cks" going on here - make the change - take control. If you use manual focus most of the time - using this technique will allow you to use AF - only when you want to - otherwise it is manual away.

I do not use a grip - these cameras are getting to big to fit into my carry aroud bag anyway. If I wanted a 3 pound body I would have bought a N*kon/C*non in the first place. I see no need (for me) to ever get a grip ----- so to speak

https://www.pentaxforums.com/forums/general-pentax-photography/14982-manual-auto-focus.html
A quote from the above thread.
It is soap box time

--------------------------------------------------------------------------------

Please allow me to get out my soapbox.

If you want to "simulate" manual techniques with AF capabilites - de-couple the AF function from the shutter button. This is possible on all Pentax DSLR's. It is something I wish I could really fix on the SF-1 (35mm autoeverything).

On the *ist Ds I use the OK button on the back to engage AF - on the K10D I use the AF button on the back (whooda thunk it).

Here is the rational - Use the OK/AF button just like when you focus manually. Once it is set - it usually stays there and on Pentax lenses, once the button is released it is easy to have a finger on the focus ring to do fine adjustments. So the overall workflow is very similar to the "good old days".
Focus on what "you want", set the exposure (can involve using the AE-L function), frame the image (compose) and shoot. Very similar to the ways of the old.

I agree that all this fuss about AF is distracting and if people who live and die by AF "speed" were handed a old all manual or even AP (aperature prefered) 35mm camera from the mid to late 70's - all their "creativity" would drain away. Welcome to the world of digital, where the computer in the camera makes more "creative" decisions that the computer behind the the viewfinder. Not to mention that they would have to advance the next frame manually - oh the humanity.

Remember - with AF - you can still be in control - break the AF/shutter button connection. Real photographers choose what is in focus - not the camera. AF is a very nice tool - but it is not a crutch - just take back control. If you need AF on the Shutter Button - put it back.

Another Quote from the same thread
yes and --- no

--------------------------------------------------------------------------------

Originally Posted by ramshot
PDL, isn't pressing the AF button to auto focus, and pressing the shutter release half way to auto focus, performing the same function?

Jeff
In a general way - yes - the half press or the AF button engage the AF subsystem, but it is how and when it is used that separate the concept.

Here is my put. Ever since I have been into photography, the act of taking a picture is basically the same. I focus on the thing that I want in focus, use what ever black magic I have to screw up the exposure - then I frame the image and shoot. During this period of time the exposure meter was always linked to the shutter button - so I had to push the shutter button to activate the light meter. Focusing was done by choosing the subject and using the split screen prism and ground glass mat screen to determine what I wanted to be the focus point. The object used to set the exposure was not necessarily the same object as the focus.

Now enter the autoeverything SLR (my first and most frustrating one was a Pentax SF-1). With autofocus the object in the center of the focus screen was put into focus when I pushed the button as was the exposure. Back in those days, at least for the Tokina 28-70mm I got with the camera, to manually focus you had to turn off AF or you would chew up the AF motor - no clutch on the lens. This meant that I how had the camera making two decisions for me right out of the box and I take that to mean that the camera is making choices that are mine.

Now comes the DSLR and the autofocus default settings are still there - the camera wants to make those decisions for me again. But - I go to a week long photo workshop and the three pros who are instructors - to a person - said 'de-couple AF from the shutter - take back control'.

Here is a scenario. I decide to take an image of some flowers but I do not want the one in the center to be in focus - I want the one in the back to be in focus. I pick up the camera and pick the first flower I can see push the AF button and look at the composition - I decide that that composition is cr*p but realize that the exposure should be based on this "thing" - so I push the shutter button half way and hit AE-L. Now I want a flower in the back to be in focus, I point the center AF (I have it set to the center point) and push the AF button - but wait - a better composition jumps out - I move the AF point hit AF again and now the image has the point of interest. Now I go about composing the shot - moving the in focus image to the point in the viewfinder that makes the image work.

To do this with a coupled AF/shutter would have mean that I would have -- release the shutter to get the AF to engage, blowing the AE-L and causing the camera to hunt - again and again until I got it the way I wanted.

So Yes - half press and AF button do the same thing - in that they turn on the AF circuits and focus. But, with the AF de-coupled it is up to me (you know the photographer) to decide what is in focus. So No they are not the same - the way I have it set up - I am more comfortable and have greater control over the function of the camera. I spent many years experimenting with DOF and using the focus ring to set the upper and lower limits to use DOF to the maximum. Letting the camera choose what is in focus basically gives you some engineers best guess - take control - it is more interesting.

AF is a way to assist the photographer to get the shot they want; moving the function from the shutter button gives me more control. Your mileage will vary.

https://www.pentaxforums.com/forums/pentax-dslr-discussion/7780-k10d-af-button-halp-press.html

Neeless to say, your search was not all that inclusive - as AF de-coupling is a soapbox issue of mine.

The Elitist - formerly known as PDL

PS: The quotes are of me - no one else is accused in this entry.

[Canada_Rockies]

I switch off half-press and use the AF button whenever I am wearing gloves, and sometimes at other times. Also with my DA* lenses, I can do a rough focus with the AF button and then touch up, without the camera refocusing for me when I press the shutter button. There are times when I do not want the camera to refocus every time I press the shutter release.