auto focus for groups

dubsider · 12-05-2014, 10:24 AM

Hey all ..
I have a family shoot * mine* where the camera will be on a tripod fired remotely..
which auto focus setting would you use ? I have typically used spot and set it on one persons cheek but that person may move?
I assume auto-27 but would like your opinion..
thanks

Rimfiredude · 12-05-2014, 10:32 AM

Originally posted by dubsider

Hey all ..
I have a family shoot * mine* where the camera will be on a tripod fired remotely..
which auto focus setting would you use ? I have typically used spot and set it on one persons cheek but that person may move?
I assume auto-27 but would like your opinion..
thanks

Auto or Pre Focus and turn off the Auto Focus.

Ptr_Mrtn · 12-05-2014, 10:32 AM

Focus on someone in the middle then switch to manual focus so it doesn't change. Just use a wide angle lens and smaller fstop, like 8, and focus should be fine

aleonx3 · 12-05-2014, 10:36 AM

You didn't mention what camera you will be using...
Use the AF button to obtain focus, disable half-press shutter to 'focus'; take advantage of hyperfocal distance, wider focal length and smaller aperture (like f8 as someone mentioned) if the lighting permits.

dubsider · 12-05-2014, 11:58 AM

K-3 with 1.11 firmware
half press is disable; I use the AF button. and I will have at least one Studio light so that should not be a problem

Docrwm · 12-05-2014, 11:59 AM

Depth of field is your main issue here. You need to be shooting with sufficient light to warrant a deeper depth of field to capture the people and a high enough shutter speed to stop any motion. I'd also set it to bracket if possible so you get one over, one under, and one correct exposure all at once. Good luck.

AquaDome · 12-05-2014, 12:13 PM

Originally posted by Docrwm

Depth of field is your main issue here. You need to be shooting with sufficient light to warrant a deeper depth of field to capture the people and a high enough shutter speed to stop any motion. I'd also set it to bracket if possible so you get one over, one under, and one correct exposure all at once. Good luck.

^^What he said^^
I would manual focus with aperture set to get the proper depth of field, then adjust shutter speed and ISO for proper exposure. Bracketing is a good insurance.

dubsider · 12-05-2014, 12:22 PM

great .. thanks all for the quick replies.

narual · 12-05-2014, 01:44 PM

You don't need AF at all, really. You control where your tripod will be, you know where the people will be, you know what lens you're going to use, and you can guess how many feet of depth need to be in focus. Use a depth of field calculator to set the aperture and distance for that and you can have it all ready in advance. Set it to aperture priority if you don't want to bother figuring out the best ISO and shutter speed in advance, too.

Online Depth of Field Calculator

Or short version, if you have a 24mm or wider lens, pop it on f8, prefocus to 8 feet, and put the tripod a minimum of 6 feet from the closest person and a maximum of 20 feet from the furthest back person, whatever you need to get them all in.

**chuck_c** · 12-05-2014, 05:19 PM

Originally posted by narual

Use a depth of field calculator to set the aperture and distance for that and you can have it all ready in advance. Set it to aperture priority if you don't want to bother figuring out the best ISO and shutter speed in advance, too.

Online Depth of Field Calculator

There is also a depth of field calculator for the iPhone or iPad. https://itunes.apple.com/us/app/depth-of-field-calculator/id356339910?mt=8

12-05-2014, 10:24 AM	#1
dubsider Junior Member Join Date: Mar 2009 Location: Georgia Posts: 27	auto focus for groups Hey all .. I have a family shoot * mine* where the camera will be on a tripod fired remotely.. which auto focus setting would you use ? I have typically used spot and set it on one persons cheek but that person may move? I assume auto-27 but would like your opinion.. thanks

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12-05-2014, 10:32 AM	#2
Rimfiredude Veteran Member Join Date: Oct 2014 Location: Washington Photos: Gallery Posts: 2,176	Originally posted by dubsider Hey all .. I have a family shoot * mine* where the camera will be on a tripod fired remotely.. which auto focus setting would you use ? I have typically used spot and set it on one persons cheek but that person may move? I assume auto-27 but would like your opinion.. thanks Auto or Pre Focus and turn off the Auto Focus.

12-05-2014, 10:32 AM	#3
Ptr_Mrtn Senior Member Join Date: Jan 2014 Posts: 143	Focus on someone in the middle then switch to manual focus so it doesn't change. Just use a wide angle lens and smaller fstop, like 8, and focus should be fine

12-05-2014, 10:36 AM	#4
aleonx3 Veteran Member Join Date: Jul 2007 Location: Brampton, Ontario Photos: Gallery \| Albums Posts: 3,996	You didn't mention what camera you will be using... Use the AF button to obtain focus, disable half-press shutter to 'focus'; take advantage of hyperfocal distance, wider focal length and smaller aperture (like f8 as someone mentioned) if the lighting permits.

12-05-2014, 11:58 AM	#5
dubsider Junior Member Join Date: Mar 2009 Location: Georgia Posts: 27 Original Poster	K-3 with 1.11 firmware half press is disable; I use the AF button. and I will have at least one Studio light so that should not be a problem

12-05-2014, 11:59 AM	#6
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	Depth of field is your main issue here. You need to be shooting with sufficient light to warrant a deeper depth of field to capture the people and a high enough shutter speed to stop any motion. I'd also set it to bracket if possible so you get one over, one under, and one correct exposure all at once. Good luck.

12-05-2014, 12:13 PM	#7
AquaDome Veteran Member Join Date: Jan 2014 Location: New Carlisle, IN Photos: Gallery \| Albums Posts: 1,475	Originally posted by Docrwm Depth of field is your main issue here. You need to be shooting with sufficient light to warrant a deeper depth of field to capture the people and a high enough shutter speed to stop any motion. I'd also set it to bracket if possible so you get one over, one under, and one correct exposure all at once. Good luck. ^^What he said^^ I would manual focus with aperture set to get the proper depth of field, then adjust shutter speed and ISO for proper exposure. Bracketing is a good insurance.

12-05-2014, 12:22 PM	#8
dubsider Junior Member Join Date: Mar 2009 Location: Georgia Posts: 27 Original Poster	great .. thanks all for the quick replies.

12-05-2014, 01:44 PM	#9
narual Veteran Member Join Date: Jun 2013 Location: South Bend (Notre Dame), Indiana Photos: Gallery \| Albums Posts: 1,988	You don't need AF at all, really. You control where your tripod will be, you know where the people will be, you know what lens you're going to use, and you can guess how many feet of depth need to be in focus. Use a depth of field calculator to set the aperture and distance for that and you can have it all ready in advance. Set it to aperture priority if you don't want to bother figuring out the best ISO and shutter speed in advance, too. Online Depth of Field Calculator Or short version, if you have a 24mm or wider lens, pop it on f8, prefocus to 8 feet, and put the tripod a minimum of 6 feet from the closest person and a maximum of 20 feet from the furthest back person, whatever you need to get them all in.

12-05-2014, 05:19 PM	#10
chuck_c Loyal Site Supporter Join Date: Jun 2011 Location: Westerville, OH Photos: Gallery \| Albums Posts: 1,588	Originally posted by narual Use a depth of field calculator to set the aperture and distance for that and you can have it all ready in advance. Set it to aperture priority if you don't want to bother figuring out the best ISO and shutter speed in advance, too. Online Depth of Field Calculator There is also a depth of field calculator for the iPhone or iPad. https://itunes.apple.com/us/app/depth-of-field-calculator/id356339910?mt=8