Auto-focus: how do you use it?

WildSioux · 03-21-2007, 08:20 PM

Originally posted by button

Go to the "custom setting" in menu mode. Scroll down to "AF Button Function" and press the right arrow and then chose "Enable AF". Hit "OK". Go to the next option down, "AF by press halfway" and chose "Off". Hit "OK". Done! Now, the shutter will fire at full depression, no matter the focus. Half shutter depress will no longer cause the AF to work. The "AF" button is your new "*" button.

John

Awesome! Odd that I have not seen that in the menu before

I will check it when I get home.

Solo1 · 03-24-2007, 01:42 AM

I'm surprised that you find it difficult, leave the focus mode on centre, focus on the subject by putting it in the centre spot whilst you hold the shutter button half way down just swing the camera to take in whatever part of the scene you want and press all the way down, ipso facto, the scene you want with the area you want in focus.It takes no time at all to do it, I will admit that very fast moving sport, or wildlife is difficult then you take the item you want in focus which is in the centre of the scene and just make sure you have enough width in the entire scene to crop. Your photo of the No1 boy with the Basket ball is smack in the centre of the scene, you must have had the focus point on auto or select to miss him.
I never shift the focus point from the centre position, then you always know where it is.
Take a few test shots, you will find it grows on you after a short time

PDL · 03-24-2007, 11:36 AM - **1 Like**

In my case it is because I am not willing to give over control to the camera. I want to be in control of what is in focus. AF is nice but if you let the machine do all the work - you have a very expensive P&S on your hands. Nearly every advanced photographer and every pro I have talked with decouple AF from the shutter button.

If you use the default --- auto everything --- you will get perhaps 95% properly exposed in focus pictures. I like to live in that 5% that the camera defaults do not cover. Take a look at the image I posted in this thread - if I had used the defaults - the wrong flower would be in focus and the exposure would not be all that good either. The focus is on the rear flower head - I metered off the forground pedal - then I composed - overall that image took about 1/2 a minute to set up.

I can not speak to shooting sports - but when I was in highschool (40 years ago) and shooting football games for the student news paper and annual I did the following. Know enough about the sport to be able to determine where the action would be. Set the f stop to provide a good image given the flash that I had. Then wait for the action to come into that "zone" take the image. Wait 6 seconds for the flash to recharge and get ready for the next play. This was using a twin lens reflex, 120 B&W film and my flash as the school only had flashbulbs.

I also shoot digital as if it were slide film - the idea is to use the frame - the entire frame - nothing but the frame. I do crop but it makes me feel as if I have failed. With digital you can push ISO, get bigger lenses, get faster lenses and post process. So do what you have to do.

As for letting the camera do all the thinking --- no --- not for me. I set the exposure, focus and composition. I purchased the camera for the sensor capabilities, the quality of the glass and its ability to let me make the decisons. I usually shoot in AV mode, I have used bulb when I started I used the P mode on my *ist DS - then I took control. Now all those "other modes" are fluff - if they disappeared - all the better. I am in control - not the cameras computer.

PDL

photog · 03-27-2007, 10:31 PM

Originally posted by Solo1

... focus on the subject by putting it in the centre spot whilst you hold the shutter button half way down just swing the camera to take in whatever part of the scene you want and press all the way down, ipso facto, the scene you want with the area you want in focus.It takes no time at all to do it...
I never shift the focus point from the centre position, then you always know where it is.
Take a few test shots, you will find it grows on you after a short time

That is exactly what I do and have done since the days when I used a Canon EOS3 (F) and before that a NIKON 801.
On the K10D there is an option that couples the area read for exposure (matrix) with the focus point.
Works for me!
Always keep in mind that the system requires some contrast in the point you select to focus on. Also the system responds to vertically contrasting bands/lines rather than horizontal lines etc.
This is proving an excellent threat; thanks to all.
Ron McDermott
Brisbane Queensland.

xfloggingkylex · 03-27-2007, 10:57 PM

my autofocus is set by half pressing the shutter release (holding the AF button disables the AF) and I have my AF-L and AE-L linked, so whatever I focus on is what I am metering on. Of course if I dont want the metering, I just press the * button and readjust.

For me this is easiest because I still have full control at my fingertips, but I save some steps with the AF-L and AE-L linked. Just half press to focus and meter, and recompose as needed. All of this is off the center focus point.

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03-21-2007, 08:20 PM	#31
WildSioux Senior Member Join Date: Mar 2007 Location: FL Posts: 103	Originally posted by button Go to the "custom setting" in menu mode. Scroll down to "AF Button Function" and press the right arrow and then chose "Enable AF". Hit "OK". Go to the next option down, "AF by press halfway" and chose "Off". Hit "OK". Done! Now, the shutter will fire at full depression, no matter the focus. Half shutter depress will no longer cause the AF to work. The "AF" button is your new "*" button. John Awesome! Odd that I have not seen that in the menu before I will check it when I get home.

03-24-2007, 01:42 AM	#32
Solo1 Inactive Account Join Date: Dec 2006 Location: Ballarat Posts: 4	I'm surprised that you find it difficult, leave the focus mode on centre, focus on the subject by putting it in the centre spot whilst you hold the shutter button half way down just swing the camera to take in whatever part of the scene you want and press all the way down, ipso facto, the scene you want with the area you want in focus.It takes no time at all to do it, I will admit that very fast moving sport, or wildlife is difficult then you take the item you want in focus which is in the centre of the scene and just make sure you have enough width in the entire scene to crop. Your photo of the No1 boy with the Basket ball is smack in the centre of the scene, you must have had the focus point on auto or select to miss him. I never shift the focus point from the centre position, then you always know where it is. Take a few test shots, you will find it grows on you after a short time

03-24-2007, 11:36 AM - 1 Like	#33
PDL Pentaxian Join Date: Oct 2006 Location: PNW USA Photos: Gallery Posts: 2,128	In my case it is because I am not willing to give over control to the camera. I want to be in control of what is in focus. AF is nice but if you let the machine do all the work - you have a very expensive P&S on your hands. Nearly every advanced photographer and every pro I have talked with decouple AF from the shutter button. If you use the default --- auto everything --- you will get perhaps 95% properly exposed in focus pictures. I like to live in that 5% that the camera defaults do not cover. Take a look at the image I posted in this thread - if I had used the defaults - the wrong flower would be in focus and the exposure would not be all that good either. The focus is on the rear flower head - I metered off the forground pedal - then I composed - overall that image took about 1/2 a minute to set up. I can not speak to shooting sports - but when I was in highschool (40 years ago) and shooting football games for the student news paper and annual I did the following. Know enough about the sport to be able to determine where the action would be. Set the f stop to provide a good image given the flash that I had. Then wait for the action to come into that "zone" take the image. Wait 6 seconds for the flash to recharge and get ready for the next play. This was using a twin lens reflex, 120 B&W film and my flash as the school only had flashbulbs. I also shoot digital as if it were slide film - the idea is to use the frame - the entire frame - nothing but the frame. I do crop but it makes me feel as if I have failed. With digital you can push ISO, get bigger lenses, get faster lenses and post process. So do what you have to do. As for letting the camera do all the thinking --- no --- not for me. I set the exposure, focus and composition. I purchased the camera for the sensor capabilities, the quality of the glass and its ability to let me make the decisons. I usually shoot in AV mode, I have used bulb when I started I used the P mode on my *ist DS - then I took control. Now all those "other modes" are fluff - if they disappeared - all the better. I am in control - not the cameras computer. PDL

03-27-2007, 10:31 PM	#34
photog Senior Member Join Date: Mar 2007 Location: Brisbane, Qld, Australia Posts: 165	Originally posted by Solo1 ... focus on the subject by putting it in the centre spot whilst you hold the shutter button half way down just swing the camera to take in whatever part of the scene you want and press all the way down, ipso facto, the scene you want with the area you want in focus.It takes no time at all to do it... I never shift the focus point from the centre position, then you always know where it is. Take a few test shots, you will find it grows on you after a short time That is exactly what I do and have done since the days when I used a Canon EOS3 (F) and before that a NIKON 801. On the K10D there is an option that couples the area read for exposure (matrix) with the focus point. Works for me! Always keep in mind that the system requires some contrast in the point you select to focus on. Also the system responds to vertically contrasting bands/lines rather than horizontal lines etc. This is proving an excellent threat; thanks to all. Ron McDermott Brisbane Queensland.

03-27-2007, 10:57 PM	#35
xfloggingkylex Senior Member Join Date: Mar 2007 Location: Frederick, MD USA Posts: 111	my autofocus is set by half pressing the shutter release (holding the AF button disables the AF) and I have my AF-L and AE-L linked, so whatever I focus on is what I am metering on. Of course if I dont want the metering, I just press the * button and readjust. For me this is easiest because I still have full control at my fingertips, but I save some steps with the AF-L and AE-L linked. Just half press to focus and meter, and recompose as needed. All of this is off the center focus point.