Purpose of multiple focus points?

**mroeder75** · 03-05-2019, 12:19 AM

What is the purpose of multiple focus points? With my old ME Super, I just lined up the focus with the line in the middle.

Do these focus points just give an average focus over the breadth of all focus points? They can't possibly focus on everything in the field of focus points if depth is different on each point.

Wouldn't I do better to have one focus point to keep my focus on what I was to focus upon?

Sandy Hancock · 03-05-2019, 12:25 AM - **1 Like**

Tracking of moving objects.
Focussing deliberately on objects not in the centre of the frame.
I'm sure there are others.

**BarryE** · 03-05-2019, 01:01 AM

As Sandy says, for tracking moving objects, but ... perhaps panning can give better, more controlled shots. It would be interesting to see how many users have their usual settings on anything other than spot/centre for stills. It is one of the first things I do when I set up user settings on any camera I've owned. Using a point focus either through Live View or just locking focus and re-composing is an ingrained technique. Why leave the camera to guess what I want in focus?

Paul the Sunman · 03-05-2019, 01:25 AM - **2 Likes**

I use centre spot focus most of the time, but area focus for birds in flight for example, and sometimes for street photography where things are changing too rapidly for me to spot focus. And of course, I often move single spot focus off centre.

**BigMackCam** · 03-05-2019, 01:40 AM - **3 Likes**

Like Paul, I use centre spot most of the time, but if I'm shooting a moving object I'll switch to area.

I also find myself using a single selectable AF point more often these days when focusing on an off-centre target, especially when I'm shooting at faster apertures and, hence, shallower depth of field. Focus and recompose isn't the most accurate approach in these situations, particularly with lenses that have pronounced field curvature...

Medex · 03-05-2019, 04:56 AM

Originally posted by BigMackCam

Like Paul, I use centre spot most of the time, but if I'm shooting a moving object I'll switch to area.

I also find myself using a single selectable AF point more often these days when focusing on an off-centre target, especially when I'm shooting at faster apertures and, hence, shallower depth of field. Focus and recompose isn't the most accurate approach in these situations, particularly with lenses that have pronounced field curvature...

How do you find focus accuracy using off-center focus points with let's say f1,4 lenses. Those focus points have f5,6 sensitivity, so IMHO the accurate focus with fast lenses are quite challengable for the camera.

**BigMackCam** · 03-05-2019, 05:13 AM - **1 Like**

Originally posted by Medex

How do you find focus accuracy using off-center focus points with let's say f1,4 lenses. Those focus points have f5,6 sensitivity, so IMHO the accurate focus with fast lenses are quite challengable for the camera.

Honestly, I very rarely shoot at f/1.4 in those situations. I'm more likely to shoot at f/2.8 - f/4 (sometimes smaller still) depending on the focal length and how much subject isolation I want. Going back briefly through my catalogue, most of the wide open stuff I've shot has been central to the frame, and many are just test shots, playing around with a lens to see what it can do

At my usual apertures, there's enough depth of field to allow for very slight focus inaccuracy. I haven't noticed any significant problems with my approach, but my tolerance for focus accuracy might be slightly different to yours...

photoptimist · 03-05-2019, 07:22 AM - **2 Likes**

Off-center compositions (typically rule-of-thirds) is my primary use of off-center focus points

For portraits of a musician at a concert, I'll set the focus point one-third over in the frame, angle the camera so the musician's face is under the focus point, and shoot away.

For these kinds of events, there's no time for focus-and-recompose because the facial expressions are constantly changing.

**mroeder75** · 03-05-2019, 07:51 AM

Originally posted by photoptimist

Off-center compositions (typically rule-of-thirds) is my primary use of off-center focus points

For portraits of a musician at a concert, I'll set the focus point one-third over in the frame, angle the camera so the musician's face is under the focus point, and shoot away.

For these kinds of events, there's no time for focus-and-recompose because the facial expressions are constantly changing.

You all have given me advice I need that I can generally use single point focusing. I do not know how to change to single point focus but can figure it out. How do you change he focus point within the frame?

I achieve some of the same off-center focus as you describe by switching from AF to MF and panning. Now if I could just compose my photo better.

derekkite · 03-05-2019, 09:44 AM

What mode are you using there? What I would do is center point focus, focus on the fawn, then reframe. If you want to move the focus point that is active, it depends on the model. The K1 there is a button above the four button pad that toggles point selection. The K3 was different. Look at your manual.

**Just1MoreDave** · 03-05-2019, 09:55 AM

Originally posted by mroeder75

You all have given me advice I need that I can generally use single point focusing. I do not know how to change to single point focus but can figure it out. How do you change he focus point within the frame?

There's a switch on the back of the camera, between the green button and LV button. That goes between single point, SEL (to select your own point), and AUTO. If you switch to SEL you can move the point around with the arrow keys. You should experiment with moving the point, maybe using the back button for focusing too. The idea is to find something that works best for you among many options.

**clickclick** · 03-05-2019, 10:18 AM

There have been a lot of good posts on how they can be used. I am also going to throw out the cynical response that it's becoming a marketing item. I can't tell you how many you really need, but my guess is some of these specs are hitting the silly level.

**Larrymc** · 03-05-2019, 11:41 AM

Originally posted by mroeder75

You all have given me advice I need that I can generally use single point focusing. I do not know how to change to single point focus but can figure it out. How do you change he focus point within the frame?

I achieve some of the same off-center focus as you describe by switching from AF to MF and panning. Now if I could just compose my photo better.

You might want to not be zoomed in so tightly and you would have a wider FOV that would allow cropping to change your composition just a bit and also allow the use of an alternate focus point once you get familiar with that feature.

**mroeder75** · 03-05-2019, 12:16 PM

Originally posted by Larrymc

You might want to not be zoomed in so tightly and you would have a wider FOV that would allow cropping to change your composition just a bit and also allow the use of an alternate focus point once you get familiar with that feature.

You are right; I don't do enough cropping. I would guess this doe will return to the cemetery with new fawns this year, if she survives winter.She used the cemetery for her daycare starting around May or June and continuing much of last summer. She would return to pick up her fawns daily between about 4:30 - 6:30 p.m. I may have the opportunity to take better deer photos this coming summer.

**mroeder75** · 03-06-2019, 10:17 PM

Originally posted by Just1MoreDave

There's a switch on the back of the camera, between the green button and LV button. That goes between single point, SEL (to select your own point), and AUTO. If you switch to SEL you can move the point around with the arrow keys. You should experiment with moving the point, maybe using the back button for focusing too. The idea is to find something that works best for you among many options.

I hope you can help me out. I have a K5. I am trying to experiment, as you suggest. This 3-way switch has a box with a single point in the center - what is that for?

SEL: What is that for?

And a green box that says auto. What is it for?

Somehow in Live view I have so many things unrelated to focus points showing when I am merely trying to work on focus points I am not sure if I pressed a wrong button, that wants me to work on white balance, or what is gong on here. I have thought of upgrading cameras, but this one is so advanced, and I can't figure it out even with reading the manual. I am open to assistance.

03-05-2019, 12:19 AM	#1
mroeder75 Site Supporter Join Date: Sep 2014 Location: Iowa Photos: Gallery Posts: 1,597	Purpose of multiple focus points? What is the purpose of multiple focus points? With my old ME Super, I just lined up the focus with the line in the middle. Do these focus points just give an average focus over the breadth of all focus points? They can't possibly focus on everything in the field of focus points if depth is different on each point. Wouldn't I do better to have one focus point to keep my focus on what I was to focus upon?

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03-05-2019, 12:25 AM - 1 Like	#2
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,272	Tracking of moving objects. Focussing deliberately on objects not in the centre of the frame. I'm sure there are others.

03-05-2019, 01:01 AM	#3
BarryE Site Supporter Join Date: Jan 2013 Location: Hampshire, UK Posts: 1,653	As Sandy says, for tracking moving objects, but ... perhaps panning can give better, more controlled shots. It would be interesting to see how many users have their usual settings on anything other than spot/centre for stills. It is one of the first things I do when I set up user settings on any camera I've owned. Using a point focus either through Live View or just locking focus and re-composing is an ingrained technique. Why leave the camera to guess what I want in focus?

03-05-2019, 01:25 AM - 2 Likes	#4
Paul the Sunman Pentaxian Join Date: Aug 2011 Location: Melbourne Photos: Gallery Posts: 4,843	I use centre spot focus most of the time, but area focus for birds in flight for example, and sometimes for street photography where things are changing too rapidly for me to spot focus. And of course, I often move single spot focus off centre.

03-05-2019, 01:40 AM - 3 Likes	#5
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,670	Like Paul, I use centre spot most of the time, but if I'm shooting a moving object I'll switch to area. I also find myself using a single selectable AF point more often these days when focusing on an off-centre target, especially when I'm shooting at faster apertures and, hence, shallower depth of field. Focus and recompose isn't the most accurate approach in these situations, particularly with lenses that have pronounced field curvature...

03-05-2019, 04:56 AM	#6
Medex Pentaxian Join Date: May 2013 Location: Vilnius Posts: 1,020	Originally posted by BigMackCam Like Paul, I use centre spot most of the time, but if I'm shooting a moving object I'll switch to area. I also find myself using a single selectable AF point more often these days when focusing on an off-centre target, especially when I'm shooting at faster apertures and, hence, shallower depth of field. Focus and recompose isn't the most accurate approach in these situations, particularly with lenses that have pronounced field curvature... How do you find focus accuracy using off-center focus points with let's say f1,4 lenses. Those focus points have f5,6 sensitivity, so IMHO the accurate focus with fast lenses are quite challengable for the camera.

03-05-2019, 05:13 AM - 1 Like	#7
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,670	Originally posted by Medex How do you find focus accuracy using off-center focus points with let's say f1,4 lenses. Those focus points have f5,6 sensitivity, so IMHO the accurate focus with fast lenses are quite challengable for the camera. Honestly, I very rarely shoot at f/1.4 in those situations. I'm more likely to shoot at f/2.8 - f/4 (sometimes smaller still) depending on the focal length and how much subject isolation I want. Going back briefly through my catalogue, most of the wide open stuff I've shot has been central to the frame, and many are just test shots, playing around with a lens to see what it can do At my usual apertures, there's enough depth of field to allow for very slight focus inaccuracy. I haven't noticed any significant problems with my approach, but my tolerance for focus accuracy might be slightly different to yours...

03-05-2019, 07:22 AM - 2 Likes	#8
photoptimist Pentaxian Join Date: Jul 2016 Photos: Albums Posts: 5,122	Off-center compositions (typically rule-of-thirds) is my primary use of off-center focus points For portraits of a musician at a concert, I'll set the focus point one-third over in the frame, angle the camera so the musician's face is under the focus point, and shoot away. For these kinds of events, there's no time for focus-and-recompose because the facial expressions are constantly changing.

03-05-2019, 09:44 AM	#10
derekkite Pentaxian Join Date: Sep 2011 Location: Nelson B.C. Posts: 3,782	What mode are you using there? What I would do is center point focus, focus on the fawn, then reframe. If you want to move the focus point that is active, it depends on the model. The K1 there is a button above the four button pad that toggles point selection. The K3 was different. Look at your manual.

03-05-2019, 09:55 AM	#11
Just1MoreDave Site Supporter Join Date: Feb 2007 Location: Aurora, CO Photos: Gallery \| Albums Posts: 6,340	Originally posted by mroeder75 You all have given me advice I need that I can generally use single point focusing. I do not know how to change to single point focus but can figure it out. How do you change he focus point within the frame? There's a switch on the back of the camera, between the green button and LV button. That goes between single point, SEL (to select your own point), and AUTO. If you switch to SEL you can move the point around with the arrow keys. You should experiment with moving the point, maybe using the back button for focusing too. The idea is to find something that works best for you among many options.

03-05-2019, 10:18 AM	#12
clickclick Loyal Site Supporter Join Date: May 2016 Location: East Coast Posts: 2,903	There have been a lot of good posts on how they can be used. I am also going to throw out the cynical response that it's becoming a marketing item. I can't tell you how many you really need, but my guess is some of these specs are hitting the silly level.

03-05-2019, 11:41 AM	#13
Larrymc Site Supporter Join Date: Jun 2014 Location: Mississippi, USA Posts: 5,251	Originally posted by mroeder75 You all have given me advice I need that I can generally use single point focusing. I do not know how to change to single point focus but can figure it out. How do you change he focus point within the frame? I achieve some of the same off-center focus as you describe by switching from AF to MF and panning. Now if I could just compose my photo better. You might want to not be zoomed in so tightly and you would have a wider FOV that would allow cropping to change your composition just a bit and also allow the use of an alternate focus point once you get familiar with that feature.

03-05-2019, 12:16 PM	#14
mroeder75 Site Supporter Join Date: Sep 2014 Location: Iowa Photos: Gallery Posts: 1,597 Original Poster	Originally posted by Larrymc You might want to not be zoomed in so tightly and you would have a wider FOV that would allow cropping to change your composition just a bit and also allow the use of an alternate focus point once you get familiar with that feature. You are right; I don't do enough cropping. I would guess this doe will return to the cemetery with new fawns this year, if she survives winter.She used the cemetery for her daycare starting around May or June and continuing much of last summer. She would return to pick up her fawns daily between about 4:30 - 6:30 p.m. I may have the opportunity to take better deer photos this coming summer.

03-06-2019, 10:17 PM	#15
mroeder75 Site Supporter Join Date: Sep 2014 Location: Iowa Photos: Gallery Posts: 1,597 Original Poster	Originally posted by Just1MoreDave There's a switch on the back of the camera, between the green button and LV button. That goes between single point, SEL (to select your own point), and AUTO. If you switch to SEL you can move the point around with the arrow keys. You should experiment with moving the point, maybe using the back button for focusing too. The idea is to find something that works best for you among many options. I hope you can help me out. I have a K5. I am trying to experiment, as you suggest. This 3-way switch has a box with a single point in the center - what is that for? SEL: What is that for? And a green box that says auto. What is it for? Somehow in Live view I have so many things unrelated to focus points showing when I am merely trying to work on focus points I am not sure if I pressed a wrong button, that wants me to work on white balance, or what is gong on here. I have thought of upgrading cameras, but this one is so advanced, and I can't figure it out even with reading the manual. I am open to assistance.