trouble focusing EX3 at DVinfo.net

Roger Sherman · August 18th, 2012, 05:31 PM

I've just rented an EX3 to test. big shoot in 2 weeks. i'm having serious problems focusing even in full manual. at f8 full wide looking at my cottage i can't tell when it's in or out of focus rotating the barrel fully. is this a low res view finder? very troubling since I've heard such great things abou this camera. auto focus is not an option.

Robin Probyn · August 18th, 2012, 07:45 PM

Im sure its not the best VF in the world.. even so you should be able to tell focus.. sounds more like a back focus issue.. been other posts about the same issues.. I think there is a menu item about setting BF.. or better still just take it back to the rental house..

Alastair Traill · August 18th, 2012, 11:26 PM

Hi Roger,

If the image cannot be brought into focus the first thing to check is whether various viewfinder symbols are sharp. If they are not the finder’s dioptric adjustment needs to be adjusted to match your eyesight. If this is the problem use ring provided.
Focusing is more critical at wide apertures, use the widest aperture possible and use the ND filters if necessary.
There are two ways provided to make focusing more critical, one is to use the “expanded focus” option that enlarges the center of the frame for a short time.
The other option is “focus assist” that when adjusted correctly places a coloured fringe around objects in focus.
The finder is not critical enough to tell whether wide-angle shots are focused so set focus using a long focal length then adjust to the desired setting. In your tests it is important to check that sharpness is maintained during a zoom. If it is not maintained then the back focus will need to be adjusted. The procedure has been described in other posts.

Olof Ekbergh · August 19th, 2012, 07:18 AM

Alastair is right on with his advice.

I would just like to point out that the kit lens on the EX3 is at its best between f2.8 and f5.6. So I always try to shoot in that range. When all the way wide the dof of the lens at 5.6 is huge, so you will not notice much difference in focus until you get to the very close end of the focus.

Also when all the way wide it is a good idea to be as open as possible so that dust on the lens does not show up. NDs are your friend.

There is also a very useful focus indicator that can be turned on in the VF, it shows the focus range on a scale, it is very accurate, I often use that when in a rush.

August 18th, 2012, 05:31 PM	#1
Roger Sherman New Boot Join Date: Mar 2009 Location: new york, ny Posts: 6	trouble focusing EX3 I've just rented an EX3 to test. big shoot in 2 weeks. i'm having serious problems focusing even in full manual. at f8 full wide looking at my cottage i can't tell when it's in or out of focus rotating the barrel fully. is this a low res view finder? very troubling since I've heard such great things abou this camera. auto focus is not an option.

August 18th, 2012, 07:45 PM	#2
Robin Probyn Major Player Join Date: Jan 2010 Location: Tokyo Posts: 590	Re: trouble focusing EX3 Im sure its not the best VF in the world.. even so you should be able to tell focus.. sounds more like a back focus issue.. been other posts about the same issues.. I think there is a menu item about setting BF.. or better still just take it back to the rental house..

August 18th, 2012, 11:26 PM	#3
Alastair Traill Major Player Join Date: Nov 2008 Location: Melbourne Australia Posts: 626	Re: trouble focusing EX3 Hi Roger, If the image cannot be brought into focus the first thing to check is whether various viewfinder symbols are sharp. If they are not the finder’s dioptric adjustment needs to be adjusted to match your eyesight. If this is the problem use ring provided. Focusing is more critical at wide apertures, use the widest aperture possible and use the ND filters if necessary. There are two ways provided to make focusing more critical, one is to use the “expanded focus” option that enlarges the center of the frame for a short time. The other option is “focus assist” that when adjusted correctly places a coloured fringe around objects in focus. The finder is not critical enough to tell whether wide-angle shots are focused so set focus using a long focal length then adjust to the desired setting. In your tests it is important to check that sharpness is maintained during a zoom. If it is not maintained then the back focus will need to be adjusted. The procedure has been described in other posts.

August 19th, 2012, 07:18 AM	#4
Olof Ekbergh Sponsor: Westside AV Join Date: Dec 2008 Location: Mount Washington Valley, NH, USA Posts: 1,365	Re: trouble focusing EX3 Alastair is right on with his advice. I would just like to point out that the kit lens on the EX3 is at its best between f2.8 and f5.6. So I always try to shoot in that range. When all the way wide the dof of the lens at 5.6 is huge, so you will not notice much difference in focus until you get to the very close end of the focus. Also when all the way wide it is a good idea to be as open as possible so that dust on the lens does not show up. NDs are your friend. There is also a very useful focus indicator that can be turned on in the VF, it shows the focus range on a scale, it is very accurate, I often use that when in a rush. __________________ Olof Ekbergh • olof@WestsideAV.com Westside A V Studios • http://www.WestsideAVstore.com/