Auto Focus VS. Manual Focus at DVinfo.net

Andrew Kiu · May 11th, 2004, 07:20 PM

Why there is a focusing problem (out of Focus using Auto focus setting (Auto Mode)) in almost every shot and will happen almost 2 – 3 times during the shoot. When I playback some footage and frustrated to see some scene “Blur” and focus again. Is my Xl1s lens defective or needs to be sent back to repair? Will it be the same problem with Manual focus?

Any ideas?

Rob Lohman · May 12th, 2004, 04:35 AM

Well, not much information to begin with. Will it do it with manual
focus? Don't know. Depends. Why not try it yourself? Yes, your
lens might be defect, or not. Try to shoot under the same
circumstances and both auto and manual settings.

The XL1 lens is known to easily hunt for focus, especially in low
light conditions or when objects are at various distances from
the lens.

I always shoot full manual including focus. Never had a problem
that way.

As always, try it out yourself and see what happens!

Nathan Gifford · May 12th, 2004, 12:42 PM

The advice on almost all cams is to shoot in manual focus mode. Any changes in the scene may cause the cam to refocus.

The XL-1 is a easy camera to use in manual focus (alright, easy to manually autofocus). The autofocus switch is on the side of lens barrel. By merely touching the focus switch you can retrigger the autofocus; this is the way probably most of the auto lens users focus.

Also remember to watch your depth-of-field (DOF). Some people have forgotten about this and don't realize that changes in the subject position relative to the lens will have an impact on focus.

Andrew Kiu · May 12th, 2004, 06:12 PM

thanks guys
Nathan Gifford
How you guy control the manual focusing in Event, show or location shot that required moving camera or panning the lens?

Norman Woo · May 13th, 2004, 01:02 AM

The way I do it is to keep my left first finger on top of the push focus button. Then as I see the subject moving closer or farther away (thus becoming out of focus), I would press/tap on the button until it comes back into focus. This way you have control over the camera when to focus. But you will need to quickly release the button once it comes back into focus or else it will start focus "hunting".

Graham Bernard · May 13th, 2004, 02:29 AM

Think about filming the first dance of the Happy Couple at their wedding. Dance floor, coming towards you and going away. Think about refocusing while they are doing this . . yes stay at the same distance and make sure the distance between you and them don't change? Yes? . . well here yah go . .learn this form a wedding videographer . .you learn a lot from these guys and gals . . Zoom well in FULL to a point just beyond the centre of the dance floor. Maybe on the OTHER side of the dance floor. Focus on a sharp definable point AT this distance and in this FULL zoomed in point. Now zoom back. Everything - mostly - between you and your cammie and the Couple should be in focus. Now, if they or you should move towards OR away will be mostly sharp.

Hope this helps .. I've given this Wedding experience . .but of course you could experiment with anything that is an event and try it out first. Okay your point about quickly changing things - event shoots - and the focus options are very interesting. Is a little "focus hunt" acceptable to NOT getting anything AND maybe using the focus ring to get THE shot - GOOD CALL! This is down to experience. Look at some really high pro news reports . .watch for the Focus hunt . .watch for the repositioning of the cameraman and the subject . . . see what the Editor did to get round this . . there are solutions . . sometimes it shouldn't be on your back to solve them all . . be kind to yourself and see what "compromises" can be discussed with others OR see what you can potentially get away with, with your own editing . . alot of the "creative" final style and content AND focal sharpness is going to be a compromise - That which is available AND that which is doable . .Don't forget our own eyes do a pretty good job at giving us the a refocus - cammies aint near it . . Us using our thumbs or fingers on the focus ring wont ever get near to our eyes - BUT our eyes will see and be very critical of our work . . again compromise.

Does this help?

Grazie

May 11th, 2004, 07:20 PM	#1
Andrew Kiu Regular Crew Join Date: Aug 2003 Location: BRUNEI Posts: 108	Auto Focus VS. Manual Focus Why there is a focusing problem (out of Focus using Auto focus setting (Auto Mode)) in almost every shot and will happen almost 2 – 3 times during the shoot. When I playback some footage and frustrated to see some scene “Blur” and focus again. Is my Xl1s lens defective or needs to be sent back to repair? Will it be the same problem with Manual focus? Any ideas? __________________ Andrew

May 12th, 2004, 04:35 AM	#2
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	Well, not much information to begin with. Will it do it with manual focus? Don't know. Depends. Why not try it yourself? Yes, your lens might be defect, or not. Try to shoot under the same circumstances and both auto and manual settings. The XL1 lens is known to easily hunt for focus, especially in low light conditions or when objects are at various distances from the lens. I always shoot full manual including focus. Never had a problem that way. As always, try it out yourself and see what happens! __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

May 12th, 2004, 12:42 PM	#3
Nathan Gifford Wrangler Join Date: Sep 2001 Location: Tickfaw, LA Posts: 1,217	The advice on almost all cams is to shoot in manual focus mode. Any changes in the scene may cause the cam to refocus. The XL-1 is a easy camera to use in manual focus (alright, easy to manually autofocus). The autofocus switch is on the side of lens barrel. By merely touching the focus switch you can retrigger the autofocus; this is the way probably most of the auto lens users focus. Also remember to watch your depth-of-field (DOF). Some people have forgotten about this and don't realize that changes in the subject position relative to the lens will have an impact on focus. __________________ Nathan Gifford Southern Cyclist Magazine & Productions For quick answers try our Search! To see me and Rob Lohman click here

May 12th, 2004, 06:12 PM	#4
Andrew Kiu Regular Crew Join Date: Aug 2003 Location: BRUNEI Posts: 108	thanks guys Nathan Gifford How you guy control the manual focusing in Event, show or location shot that required moving camera or panning the lens? __________________ Andrew

May 13th, 2004, 02:29 AM	#6
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Some Ideas . .and being good to yourself! Keeping Focus in Perspective - HAH! Think about filming the first dance of the Happy Couple at their wedding. Dance floor, coming towards you and going away. Think about refocusing while they are doing this . . yes stay at the same distance and make sure the distance between you and them don't change? Yes? . . well here yah go . .learn this form a wedding videographer . .you learn a lot from these guys and gals . . Zoom well in FULL to a point just beyond the centre of the dance floor. Maybe on the OTHER side of the dance floor. Focus on a sharp definable point AT this distance and in this FULL zoomed in point. Now zoom back. Everything - mostly - between you and your cammie and the Couple should be in focus. Now, if they or you should move towards OR away will be mostly sharp. Hope this helps .. I've given this Wedding experience . .but of course you could experiment with anything that is an event and try it out first. Okay your point about quickly changing things - event shoots - and the focus options are very interesting. Is a little "focus hunt" acceptable to NOT getting anything AND maybe using the focus ring to get THE shot - GOOD CALL! This is down to experience. Look at some really high pro news reports . .watch for the Focus hunt . .watch for the repositioning of the cameraman and the subject . . . see what the Editor did to get round this . . there are solutions . . sometimes it shouldn't be on your back to solve them all . . be kind to yourself and see what "compromises" can be discussed with others OR see what you can potentially get away with, with your own editing . . alot of the "creative" final style and content AND focal sharpness is going to be a compromise - That which is available AND that which is doable . .Don't forget our own eyes do a pretty good job at giving us the a refocus - cammies aint near it . . Us using our thumbs or fingers on the focus ring wont ever get near to our eyes - BUT our eyes will see and be very critical of our work . . again compromise. Does this help? Grazie

May 13th, 2004, 01:02 AM	#5
Norman Woo Regular Crew Join Date: Jan 2002 Location: Brossard, Quebec, Canada Posts: 147	The way I do it is to keep my left first finger on top of the push focus button. Then as I see the subject moving closer or farther away (thus becoming out of focus), I would press/tap on the button until it comes back into focus. This way you have control over the camera when to focus. But you will need to quickly release the button once it comes back into focus or else it will start focus "hunting".

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