Front / Back Focusing Testing

[USM]

Since there are so many instances of front or back focusing problem of EF lenses, here is a test of your eye sight to tell whether which problem exists or none at all.

At f4



At f5.6



At f8

[Kit]

Where's the option for "if I don't see it on the actual images I sell to the clients, I don't give a damn."

[fWord]

Heheh...just waiting to see how sharp my eyes and my brain really is. I think this involves some knowledge and theory.

[knoxknocks]

your lens is perfectly fine - provided you focused on the focus line, of course

[user111]

where to get all these kind of charts

[USM]

Originally Posted by user111 where to get all these kind of charts

Brother, you still got time to look for charts? Your account might be deregistered anytime.

[shinken]

Originally Posted by user111 where to get all these kind of charts

Here you go:

[user111]

who the hell cares? the chart is more important to me

[Achromatic]

Originally Posted by shinken Here you go:

Another one here....http://www.canon-dslr.com/Canon_Jan0...Focus_Test.htm

[viper_chad]

If i get a front or back focusing problem, how much will I spend to repair this?

[Goldenstars08]

Originally Posted by shinken Here you go:

Thank for the site...

[donkuok]

can I use the kit lens to test the back focusing issue?
I did a few tests on the kit lens. I found that the focusing is not stable...sometimes got a slight back focusing, abount 5mm.
For ur info, I didnt use the focus chart, however, I used 3 same objects aligned them in diff distance about 5mm diff of the 3 objects

[donkuok]

anyone pls comment on my previous post. thanks

[donkuok]

ISO100, 18mm@F/3.5, 1/4s, tripod with remote shutter. Focus point center but it focus the left one which is 0.5cm behind the center AA batt.
Shall I send in for servicing???

[donkuok]

Noone comment...looks like nobody experience this problem huh...

[donkuok]

ok..looks like I am alone la......just sent in to Canon service centre at Funan. They said they need min 5 days...

[fWord]

Originally Posted by donkuok ISO100, 18mm@F/3.5, 1/4s, tripod with remote shutter. Focus point center but it focus the left one which is 0.5cm behind the center AA batt. Shall I send in for servicing???

Perhaps this supposed back-focusing issue in your lens is a result of the subject being too close? The minimum subject distance for the kit lens is 28cm, I think.

[+evenstar]

Originally Posted by fWord Perhaps this supposed back-focusing issue in your lens is a result of the subject being too close? The minimum subject distance for the kit lens is 28cm, I think.

If the objects are too close, the lens cant focus and the shutter won't fire

[donkuok]

negative.....i placed it at least 30cm. I tried many times. It always happens at wide open. When I took portrait shot., can see clearly that the ears is sharper than the face.
anyway, good la..send it for servicing to ensure the camera body is front/back focus free.

[donkuok]

Originally Posted by fWord Perhaps this supposed back-focusing issue in your lens is a result of the subject being too close? The minimum subject distance for the kit lens is 28cm, I think.

that's true!