wat's focus at infinity?

[jeanie]

is it the same as hyperfocal distance?

so how do i set focus at infinity?
i saw a thread recently on it but no definitive answer.
TIA

 

[ortega]

not the same

switch to manual focus and turn focus ring to infinity

 

[jeanie]

not the same

switch to manual focus and turn focus ring to infinity

i tried that.but in the end, objects that are about 100 meters away are oof.
so when do we use this technique?

 

[ortega]

i tried that.but in the end, objects that are about 100 meters away are oof.
so when do we use this technique?

never

 

[jeanie]

never

so it's useless.
then hyperfocal is the way to go ya.

 

[yyD70S]

About the only time I use this technique -- fireworks display -- with no interesting foreground.

i tried that.but in the end, objects that are about 100 meters away are oof.
so when do we use this technique?

 

[jeanie]

About the only time I use this technique -- fireworks display -- with no interesting foreground.

but that also depends how near u are to the fireworks display?
if you are about 200-300 meters away, and you focus at infinity, your fireworks will be blur right?

:dunno:

 

[ortega]

so it's useless.
then hyperfocal is the way to go ya.

not totally useless
depends on situation

maybe planes, or other stuff far far away

but for me, almost never use

 

[yyD70S]

Point noted.

So far, my only experiences with fireworks are distant and with wide-to-normal focal length settings.

but that also depends how near u are to the fireworks display?
if you are about 200-300 meters away, and you focus at infinity, your fireworks will be blur right?

:dunno:

 

[MDZ2]

but that also depends how near u are to the fireworks display?
if you are about 200-300 meters away, and you focus at infinity, your fireworks will be blur right?

:dunno:

I think for most lens, save the longest zoom, are already at infinity at that distance.

 

[gooseberry]

Do note that with ED glass, the point of infinity focus varies with ambient temperature and may not necessarily be at the infinity marked point on the lens (btw, that is why you can turn the focus past the infinity mark on the lens)

 

[Wisp]

I think for most lens, save the longest zoom, are already at infinity at that distance.

Blurness is not due to focus of infinity. For fireworks you often need to cap your aperture down to f4 instead of wide open aperture in order to ensure sharpness, and hence long exposure times. Use manual operations for night..period. Auto exposure is totally unreliable at night unless synced up to flash.

And use a damn tripod for goodness sake, regardless on the balance compensation in the lens.