[PDL]

What re-starts AF after it has been cancelled? Does it need to be turned off again in between the two series of shots described above?

I do not know - I have never let used the AF button to disable AF. Just plain can't answer that one.

Another thing to consider is which control dial is primarily being used. AF button doesn't work well for me if I'm using the rear e-dial -- I often end up on the EV-comp button. I run into a far more serious problem if I re-program the front e-dial to be the primary control wheel -- I have a tendency to mistake the power on/off button as the front e-dial sometimes, when moving back from the shutter, thereby shutting the camera down. Then there is the grip, which doesn't have its own AF button.

I use AV most of the time - so the rear e-dial is the f-stop. I usually set the f-stop before I get the camera up to my eye - so hitting the AF button with my thumb (I use the center AF all the time) has become second nature to me as of late. (On my *ist Ds I use the OK button to force AF). As mentioned above - I do not have a grip -- in so may ways too -- so I just do not care.

On the other hand, holding the shutter half-pressed feels like riding the clutch. Sometime it seems to me -- correct me if I'm wrong here -- that if the shutter is held half-pressed too long, it can come out of lock and restart AF, or starts to micro-adjust focus continously (you can hear the motor grinding away). This may be more damaging than anything else.

In any case, and despite the fact that I have not yet done so, my impression is that decoupling AF from the shutter is the way to go. It's just a matter of getting used to it, eventually.

I agree that holding down the shutter button is somewhat like riding the clutch. But then between most of my shots I shut the camera off (ya know - with the off switch). So with my style of shooting I do not have the shutter half pressed all that much. I usually try to anticipate when I am going to take an image, so the camera is powered up when it goes up to my eye.

As for losing AF while holding the shutter button down - I have bumped the focus ring and had to "refocus" - more that I would like to admit. However, with the shutter button? Once I learned how to use the OK button on my *ist Ds, I never went back. On my K10D and K20D the first thing I did once the battery was charged and I set the date/time - was de-couple AF from the shutter button. I have no experience with losing focus lock with shutter button only on the K10D and K20D.

Old habits die hard. (Your mileage will vary)

The Elitist - Formerly known as PDL

[snofox]

Wow, what an interesting thread! I always knew that I could disconnect AF from the shutter button, but I never really understood why that may be a useful thing to do!

Something else for me to play around with tomorrow!

[pentaxian_tmb]

While dealing with my new camera fiasco, I have been experimenting with the AF ("ok") button on my K100d Super and AV mode (I usually always shoot in manual). And a funny thing happened. By decoupling the AF button and shooting in AV mode, I actually pay more attention to each setting than when using shutter focus in full manual. Before, I often found myself just spinning dials until the camera showed a "proper" exposure and then adjusting according--seemed like a very random process (at least for fast "on the go" type shots).

With the AF button decoupled, I now have to take three distinctive steps:1) set my exposure by metering off of something close to 18% grey, adjusting the EV comp for lighting of other elements in the scene, and then locking the exposure; 2) focus on the subject of the photo with the "ok" button and 3) compose the scene.


That may sound so rudimentary..and it is.....but the point is that now I am consciously thinking about 1) what should I meter off of; 2) do I need EV comp; 3) is my focal point going to be the same as my metering point; 4) compose the scene. Before I had really lumped everything into a two-step process of compose and then focus/set exposure. Also, by using AV mode in combination with the above, I now am much more conscious of what I want my depth of field to be. I do mostly landscape/architectual photography, so I don't need to "stop" or "blur" motion that often and shutter speed is not that important.

In short, by making those few adjustments to the camera's settings, I am forced to think about each step in the process and why I want certain values.

Again, this may sound obvious to seasoned pros, but it wasn't for me. I now feel like I have much more control over my shots than before.

[jbinpg]

After thinking about this issue, I realize why I moved back to shutter AF from the AF button. It is precisely because in a fast-moving situation where I want a quick AF, my finger falls on the shutter automatically but I have to hunt for the AF button every time. That is most likely due to the size of my hands rather than anything else so this may not be the case with anybody else.

Jack

[opianstate]

this brings about a funny question - are other cameras this customizable? I just figured out last night that my k20d allows me to customize which dials do what in certain modes. I almost poo'ed myself I was so happy. For some reason I like having Aperature control under my thumb instead of my forefinger. I never heard Canikon guys bragging about having this ability

[PDL]

this brings about a funny question - are other cameras this customizable? I just figured out last night that my k20d allows me to customize which dials do what in certain modes. I almost poo'ed myself I was so happy. For some reason I like having Aperature control under my thumb instead of my forefinger. I never heard Canikon guys bragging about having this ability

I think most modern DSLR's allow the user to de-couple AF from the shutter button. I first heard about it while attending a photography workshop in 2005. The primary instructor was using a brand spanking new Canon 5d, another was shooting with a Nikon D2X - or whatever was the top of the line in 2005 - while the third was shooting a Leica M4. When I attended another one day seminar this year I asked the question as to whether the two seminar leaders de-coupled AF. Both said yes. In fact one said of all the custom settings on his Canon he used only two - show histogram on the LCD and de-couple the shutter button, everything else was default. However, since I do not have each model of every manufacturer - I can not be absolutely sure about it.

As for not being able to catch "fast moving action - with the AF button". I am so used to putting my thumb on the AF/OK button these days that it is second nature to me. I have been shooting SLR's for nearly 40 years - started out with pure manual (not a Pentax but a Fujica ST801 - the first camera with LED's instead of a needle meter in the viewfinder). So since the thought of having the camera "decide" what is going to be in focus - is alien to my old method thought processes. Besides the things I shoot don't tend to move all that much anyway.

The Elitist - formerly known as PDL

[stoge]

Easy there opianstate, we don't need any pooping right now! hold your pants on