Fastest way to focus on k-x, it's slow sometimes

crossover37 · 05-03-2010, 02:39 PM

What's the fastest way to focus on moving subjects (couple walking, kid running, etc.)? I use spot focus usually but would it be best to switch to 5 point or 11 point focus? Thanks.

gebco · 05-03-2010, 02:46 PM

I was trying BIF recently and found the best was to put it in 5 point focus; also remember to use AF-C if you are tracking.

Eruditass · 05-03-2010, 03:01 PM

Center focus point only is the fastest, followed by single points (camera doesn't need to pick). This is true on all SLRs.

hcc · 05-03-2010, 03:24 PM

I agree that Center Focus is the fastest focus method.

But remember that AF-C does not work well with continuous shooting. Another approach is to use AF-S and a short burst of continuous shots.

Ira · 05-03-2010, 03:35 PM

It also depends on the length of your lens and what you're shooting. I shot some surfboarders today on a mechanical pull on a lake with a 90 but at infinity and a bit less.

And single shooting mode worked and focused just fine.

So I echo the above comments strongly. I was extremely pleased, and this was my first attempt at something like this.

jlaubza · 05-04-2010, 10:39 PM

Either five point of single center point can be faster, depending on conditions. Where you have clear contrast variation on the main subject, single point is fast.

Where contrast is low, five point works faster.

However, five point should only be used if the subject is further than around 3 meters distant or you have not zoomed into the subject.

The reason is that a low contrast subject that is larger than the central focusing rectangle marked in the VF may result in any one of the five focusing points selecting the highest contrast area on the subject, meaning that sometimes you wont be focusing on the center of the subject.

Obviously if the subject is smaller than the central rectangle, then five point will not make a difference in focus regardless of which one of the five points actually locks onto the subject.

Equally, if you are doing landscapes, the subject distance is far enough away for any of the five points to work without impacting your focus.

So, in general, I'm using five point for quick focus but I try to remember when to change it. Either way though, there are times when it would be more effective to use the focusing setting that you are not currently using! DSLR work is not for quick snapshots.

05-03-2010, 02:39 PM	#1
crossover37 Senior Member Join Date: Mar 2010 Photos: Gallery Posts: 214	Fastest way to focus on k-x, it's slow sometimes What's the fastest way to focus on moving subjects (couple walking, kid running, etc.)? I use spot focus usually but would it be best to switch to 5 point or 11 point focus? Thanks.

05-04-2010, 10:39 PM	#6
jlaubza Senior Member Join Date: Jul 2008 Location: south africa, johannesburg Photos: Gallery Posts: 228	fast focusing on the KX Either five point of single center point can be faster, depending on conditions. Where you have clear contrast variation on the main subject, single point is fast. Where contrast is low, five point works faster. However, five point should only be used if the subject is further than around 3 meters distant or you have not zoomed into the subject. The reason is that a low contrast subject that is larger than the central focusing rectangle marked in the VF may result in any one of the five focusing points selecting the highest contrast area on the subject, meaning that sometimes you wont be focusing on the center of the subject. Obviously if the subject is smaller than the central rectangle, then five point will not make a difference in focus regardless of which one of the five points actually locks onto the subject. Equally, if you are doing landscapes, the subject distance is far enough away for any of the five points to work without impacting your focus. So, in general, I'm using five point for quick focus but I try to remember when to change it. Either way though, there are times when it would be more effective to use the focusing setting that you are not currently using! DSLR work is not for quick snapshots.

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05-03-2010, 02:46 PM	#2
gebco Veteran Member Join Date: Mar 2010 Location: Winnipeg Photos: Gallery \| Albums Posts: 329	I was trying BIF recently and found the best was to put it in 5 point focus; also remember to use AF-C if you are tracking.

05-03-2010, 03:01 PM	#3
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Center focus point only is the fastest, followed by single points (camera doesn't need to pick). This is true on all SLRs.

05-03-2010, 03:24 PM	#4
hcc Pentaxian Join Date: Nov 2009 Location: Brisbane, Australia Photos: Gallery \| Albums Posts: 4,004	I agree that Center Focus is the fastest focus method. But remember that AF-C does not work well with continuous shooting. Another approach is to use AF-S and a short burst of continuous shots.

05-03-2010, 03:35 PM	#5
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	It also depends on the length of your lens and what you're shooting. I shot some surfboarders today on a mechanical pull on a lake with a 90 but at infinity and a bit less. And single shooting mode worked and focused just fine. So I echo the above comments strongly. I was extremely pleased, and this was my first attempt at something like this.