K-X 11-point Auto Focus issue

**mjkelly62** · 03-17-2010, 02:57 PM

Hi there,

Just thought I'd add my own comments with regard this AF issue.

I also worried about the AF issue for a while before getting the Kx. It does seem a slightly odd omission to provide 11 AF points but then not give any visual indicator in the viewfinder of which point has been selected by the camera.

However, now that I have the camera, I have been able to compare it with my old and trusted Nikon D40. The D40 has 3 AF indicators spread fairly wide apart in the viewfinder. I quickly discovered that to have them all active was a waste of time as it would invariably select the wrong one when focusing. I thus resorted to the single centre point for all my photos - using the old and trusted technique of focus and recompose as discussed elsewhere in this post. Now, compared to the Kx, I do have to say, in the first instance, that it is helpful to have that indicator in the viewfinder right in front of you on the main screen, even if one is only selecting the centre point for all photos - not least because I wear glasses which makes seeing the green focus indicator at the bottom of the Kx screen slightly more problematic. On the other hand, my comparisons with the D40 has not thrown up any problems with regard focus issues with the Kx. It nearly always produces well-focused shots.

So, to sum up, I don't see the point of having 11 AF points if no visual indicator is provided in the viewfinder to indicate which point has been selected. To my mind, one might just as well have a single centre point since that is all one can rely if one uses the viewfinder for composing and focusing - I have no experience of the live view mode which probably does provide more focus-related help to the user.

One final point, I wonder if it would have been perhaps better if the camera's viewfinder had shown the focus points themselves, rather than the slightly quirky combination of square and ordinary brackets which one can see in the viewfinder. It isn't easy to see from these various brackets where the points are exactly.

Mike

Last edited by mjkelly62; 03-18-2010 at 12:26 PM.

kxr4trids · 03-17-2010, 04:07 PM

Has anyone tried the katz eye with focus area bracket option? I realize a $40 option on top of a $100 screen doesn't soothe, when the reason for getting the k-x in the first place is the price point. However, if anyone had first hand experience it might be interesting to hear.

Marc Sabatella · 03-17-2010, 06:49 PM

Originally posted by mjkelly62

So, to sum up, I don't see the point of having 11 AF points if no visual indicator is provided in the viewfinder to indicate which point has been selected.

It does in theory somewhat increase the likelhood that the camera will be able to focus where you want. Consider that with only three points, you only get correct focus if your subject happens to be in one of those three places; with 11, your subject can be in any one of 11 places and still be under one of the focus sensors. Of course, you could make 3 *really big* focus sensors, but that doesn't really help, either - it becomes that much harder to control focus when you do want that focus. Probably has technical issues in the implementation too.

Still, it remains true that if you really care at all about where focus is, you don't let the camera decide. The auto-select mode is for people who don't care that much but hope for the best, and more points does somewhat increase that likelihood, at least to a point.

Quote:

One final point, I wonder if it would have been perhaps better if the camera's viewfinder had showed the focus points themselves, rather than the slightly quirky combination of square and ordinary brackets which one can see in the viewfinder. It isn't easy to see from these various brackets where the points are exactly.

If it's any consolation, the indicators on other camera don't really help either - they just show the *centers* of the focus sensors. The actual sensors are much larger. So really, just knowing the approximate location is about as good as you'll get. I guess they could draw in rectangles on the focus screen to indicate their positions. I'm not sure the results would be less confusing.

**mjkelly62** · 03-18-2010, 12:42 PM

Hi Marc,

Thanks for replying to my post.

I agree entirely with you about being the one in control of focusing - that's why I only have the centre point active for all my auto-focus shots. I guess one has to accept that the Kx is, after all, very much in the entry-level DSLR bracket and so shouldn't expect too much with regard features. However, it is worth noting that most, if not all, entry-level offerings from other manufacturers do provide visual focus points in the viewfinders - even if some don't offer much more than was available with the D40.

On the subject of cameras that do provide indicators, you mention that they only show the "centers" of the focus sensors and that the sensors are, in actual fact, larger. Does that mean that the centre point is not necessarily where the camera focuses - i.e if I attempt to focus dead centre in the viewfinder, is it likely that this isn't where the camera is actually focusing. I only ask this as I've noticed that the camera does momentarily seem to refocus on occasions if I first focus on a spot by half-pressing the shutter button and then release the pressure on the button and then refocus again on the same spot.

Regards
Mike

Last edited by mjkelly62; 03-23-2010 at 03:15 AM.

phzy2003 · 04-07-2010, 10:38 PM

i don't use the whole 11 points much , i usually only use the centre focus point

paulo0916 · 04-09-2010, 08:37 AM

Hello everyone,

Newbie Kx owner here just last January and I would like to ask about center focus and the 11af points. When do you usually use it? If you're taking a portrait shot will you be using center focus and if it's a group picture you use 11af? Sorry for this question I'm still a noob on this and trying to understand everything. I hope you could enlighten me.

Thank you.

opiedog · 04-09-2010, 10:01 AM

i usually use the center point although i find the auto 5 to be pretty good too. think of it as a large center point AF.

you can still use center point for group shots. you can do a focus-recompose method. some folks will squirm about this, but it works most cases.

if you have time you can manually select one of the 11 AF points and do the AF, but in my experience i never use the 11 point auto.

btw, how's manila these days?

Marc Sabatella · 04-09-2010, 12:55 PM

You have to realize that regardless of how many points you llow the camera to select between, it's still going to select just one of them. It's not like the camera can magically make 11 different points all be in focus at once. So don't think that's what you are doing when you choose 11 point - it's not. You're simply giving the camera options to choose from in deciding whcih *one* point to use. The only time the 11 oints provides a real advantage is if you want the camera to choose to focus on something way off to the side, since that's where those extra focus points are. But you can generally achieve the same thing in 5 point mode, or center point mode, by simply pointing your camera directly at the subejct where you want focus to be, half-pressing the shutter and holidng it there while you recompose, then finish pressing the shutter. This is way many if not most people have shot with AF cameras since AF was first introduced in the late 1970's. In certain very rare cases you might get slight focus discrepancies this way (like when shooting at f/1.4), but that's what MF is for.

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03-17-2010, 02:57 PM	#61
mjkelly62 Site Supporter Join Date: Feb 2009 Location: Hillerød Posts: 9	Hi there, Just thought I'd add my own comments with regard this AF issue. I also worried about the AF issue for a while before getting the Kx. It does seem a slightly odd omission to provide 11 AF points but then not give any visual indicator in the viewfinder of which point has been selected by the camera. However, now that I have the camera, I have been able to compare it with my old and trusted Nikon D40. The D40 has 3 AF indicators spread fairly wide apart in the viewfinder. I quickly discovered that to have them all active was a waste of time as it would invariably select the wrong one when focusing. I thus resorted to the single centre point for all my photos - using the old and trusted technique of focus and recompose as discussed elsewhere in this post. Now, compared to the Kx, I do have to say, in the first instance, that it is helpful to have that indicator in the viewfinder right in front of you on the main screen, even if one is only selecting the centre point for all photos - not least because I wear glasses which makes seeing the green focus indicator at the bottom of the Kx screen slightly more problematic. On the other hand, my comparisons with the D40 has not thrown up any problems with regard focus issues with the Kx. It nearly always produces well-focused shots. So, to sum up, I don't see the point of having 11 AF points if no visual indicator is provided in the viewfinder to indicate which point has been selected. To my mind, one might just as well have a single centre point since that is all one can rely if one uses the viewfinder for composing and focusing - I have no experience of the live view mode which probably does provide more focus-related help to the user. One final point, I wonder if it would have been perhaps better if the camera's viewfinder had shown the focus points themselves, rather than the slightly quirky combination of square and ordinary brackets which one can see in the viewfinder. It isn't easy to see from these various brackets where the points are exactly. Mike Last edited by mjkelly62; 03-18-2010 at 12:26 PM.

03-17-2010, 04:07 PM	#62
kxr4trids Senior Member Join Date: Mar 2010 Location: VA Photos: Albums Posts: 227	Has anyone tried the katz eye with focus area bracket option? I realize a $40 option on top of a $100 screen doesn't soothe, when the reason for getting the k-x in the first place is the price point. However, if anyone had first hand experience it might be interesting to hear.

03-17-2010, 06:49 PM	#63
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	Originally posted by mjkelly62 So, to sum up, I don't see the point of having 11 AF points if no visual indicator is provided in the viewfinder to indicate which point has been selected. It does in theory somewhat increase the likelhood that the camera will be able to focus where you want. Consider that with only three points, you only get correct focus if your subject happens to be in one of those three places; with 11, your subject can be in any one of 11 places and still be under one of the focus sensors. Of course, you could make 3 really big focus sensors, but that doesn't really help, either - it becomes that much harder to control focus when you do want that focus. Probably has technical issues in the implementation too. Still, it remains true that if you really care at all about where focus is, you don't let the camera decide. The auto-select mode is for people who don't care that much but hope for the best, and more points does somewhat increase that likelihood, at least to a point. Quote: One final point, I wonder if it would have been perhaps better if the camera's viewfinder had showed the focus points themselves, rather than the slightly quirky combination of square and ordinary brackets which one can see in the viewfinder. It isn't easy to see from these various brackets where the points are exactly. If it's any consolation, the indicators on other camera don't really help either - they just show the centers of the focus sensors. The actual sensors are much larger. So really, just knowing the approximate location is about as good as you'll get. I guess they could draw in rectangles on the focus screen to indicate their positions. I'm not sure the results would be less confusing.

03-18-2010, 12:42 PM	#64
mjkelly62 Site Supporter Join Date: Feb 2009 Location: Hillerød Posts: 9	Hi Marc, Thanks for replying to my post. I agree entirely with you about being the one in control of focusing - that's why I only have the centre point active for all my auto-focus shots. I guess one has to accept that the Kx is, after all, very much in the entry-level DSLR bracket and so shouldn't expect too much with regard features. However, it is worth noting that most, if not all, entry-level offerings from other manufacturers do provide visual focus points in the viewfinders - even if some don't offer much more than was available with the D40. On the subject of cameras that do provide indicators, you mention that they only show the "centers" of the focus sensors and that the sensors are, in actual fact, larger. Does that mean that the centre point is not necessarily where the camera focuses - i.e if I attempt to focus dead centre in the viewfinder, is it likely that this isn't where the camera is actually focusing. I only ask this as I've noticed that the camera does momentarily seem to refocus on occasions if I first focus on a spot by half-pressing the shutter button and then release the pressure on the button and then refocus again on the same spot. Regards Mike Last edited by mjkelly62; 03-23-2010 at 03:15 AM.

04-07-2010, 10:38 PM	#65
phzy2003 Senior Member Join Date: Mar 2010 Location: Gold Coast, Australia Photos: Gallery Posts: 167	i don't use the whole 11 points much , i usually only use the centre focus point

04-09-2010, 08:37 AM	#66
paulo0916 Inactive Account Join Date: Mar 2010 Location: Manila Posts: 13	Hello everyone, Newbie Kx owner here just last January and I would like to ask about center focus and the 11af points. When do you usually use it? If you're taking a portrait shot will you be using center focus and if it's a group picture you use 11af? Sorry for this question I'm still a noob on this and trying to understand everything. I hope you could enlighten me. Thank you.

04-09-2010, 10:01 AM	#67
opiedog Inactive Account Join Date: Jan 2008 Location: NC Posts: 787	i usually use the center point although i find the auto 5 to be pretty good too. think of it as a large center point AF. you can still use center point for group shots. you can do a focus-recompose method. some folks will squirm about this, but it works most cases. if you have time you can manually select one of the 11 AF points and do the AF, but in my experience i never use the 11 point auto. btw, how's manila these days?

04-09-2010, 12:55 PM	#68
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	You have to realize that regardless of how many points you llow the camera to select between, it's still going to select just one of them. It's not like the camera can magically make 11 different points all be in focus at once. So don't think that's what you are doing when you choose 11 point - it's not. You're simply giving the camera options to choose from in deciding whcih one point to use. The only time the 11 oints provides a real advantage is if you want the camera to choose to focus on something way off to the side, since that's where those extra focus points are. But you can generally achieve the same thing in 5 point mode, or center point mode, by simply pointing your camera directly at the subejct where you want focus to be, half-pressing the shutter and holidng it there while you recompose, then finish pressing the shutter. This is way many if not most people have shot with AF cameras since AF was first introduced in the late 1970's. In certain very rare cases you might get slight focus discrepancies this way (like when shooting at f/1.4), but that's what MF is for.