stopping down for sharpness?

[cheekiang]

hi,

what do you mean to stop down to get sharper pictures?

and if someone say focus your lens to infinity what does he means???

chee kiang

[ExplorerZ]

Originally Posted by cheekiang hi, what do you mean to stop down to get sharper pictures? and if someone say focus your lens to infinity what does he means??? chee kiang

1) shoot at f4 or bigger f-stop rather than wide open at f2.8
2) turn focus ring to a rotated 90degree '8' sign

[cheekiang]

Originally Posted by ExplorerZ 1) shoot at f4 or bigger f-stop rather than wide open at f2.8 2) turn focus ring to a rotated 90degree '8' sign

okie for the 2nd part i still blur...focus ring? u mean the one on the lens itself? i rotate it but where got 8 sign? i using the kit lens....

please advise...

thanks

chee kiang

[zac08]

Originally Posted by cheekiang hi, what do you mean to stop down to get sharper pictures? and if someone say focus your lens to infinity what does he means??? chee kiang

Let's say your lens...

f3.5 - f5.6
at 18mm, your max aperture is f3.5 and your max aperture is f5.6 at 55mm...

so if you stop down 1 stop on each length. It will be

18mm (max is f3.5) stop down 1 stop is f5
55mm (max is f5.6) stop down 1 stop is f8

This should give you a decent sharpness in your pictures as normally, you can't get sharpness at wide open apreture.

As for infinity, it's shown by the ∞ mark on the lens.

[Kit]

The smaller the aperture, the bigger the f/no. and yields deeper Depth of View(DOF). DOF determines how much of your images is in focus. The deeper the DOF, more of your image will be in focus (so call sharp). That's not all though. Distance of your subject and focal length of your lenses are also factors which determine DOF you get. Wide angle lenses will give you deeper DOF in general.

[ExplorerZ]

Originally Posted by cheekiang okie for the 2nd part i still blur...focus ring? u mean the one on the lens itself? i rotate it but where got 8 sign? i using the kit lens.... please advise... thanks chee kiang

iirc kit lens does't have a focusing scale... u can try turning the focus ring all the way to the left or right and see which one gives you clear picture when taking picture of object very far away. that is infinitely focus.

[zoossh]

Originally Posted by cheekiang okie for the 2nd part i still blur...focus ring? u mean the one on the lens itself? i rotate it but where got 8 sign? i using the kit lens.... please advise... thanks chee kiang

point at a faraway object and focus with shutter release half pressed.

[cheekiang]

oh i see....thanks alot for all of your information...thanks....

[Witness]

they say that most lenses are sharpest when stopped down about 2-3 stops from their widest aperture..hope this helps

[cheekiang]

hi witness thanks for your info will try using your method...

chee kiang