g3: how to make use of Manual focus?

[myin]

Hi, anybody has any suggestion about using Manual focus instead of AF with G3? In what conditions the MF should be used?

In MF mode, if i wanna set the focus distance to infinity, what is the minimal distance from the lens to the objects in order for the objects not to blurred. And will the focus length of the lens affects this distance?

thanks in advance !

--
Ming

 

[gary ng]

I would suggest you to read the articles in the Glossary link first and if there is still other questions after reading them, ask again.

Hi, anybody has any suggestion about using Manual focus instead of
AF with G3? In what conditions the MF should be used?

In MF mode, if i wanna set the focus distance to infinity, what is
the minimal distance from the lens to the objects in order for the
objects not to blurred. And will the focus length of the lens
affects this distance?

thanks in advance !

--
Ming

 

[myin]

just read the glossary, quite helpful but too general. anybody can specifies particular shooting scenarios where manual foucs can perform better than AF ? anyone have such experinces ?

and another question, how to operate manul focus? measure the distance by eye only? how to calculate distance, the displacement from object to film (CCD sensor in this case) or some else. this is significant for Macro mood.

Hi, anybody has any suggestion about using Manual focus instead of
AF with G3? In what conditions the MF should be used?

In MF mode, if i wanna set the focus distance to infinity, what is
the minimal distance from the lens to the objects in order for the
objects not to blurred. And will the focus length of the lens
affects this distance?

thanks in advance !

--
Ming

--
Ming

 

[gary ng]

The problem of AF is it is SLOW and for some low light condition, it fails. So if you are focusing fast moving things or focusing indoor and fail, you need MF.

For non-macro mode, you guesstimate the distance and since the DOF of G3(and all digital camera with small CCD) is very deep, you don't need to be exactly accurate.

For macro, you don't usually need MF as it is not some fast moving subject and the lighting condition are usually not bad. Beside, there is focus bracketing in G3 which is designed with macro in mind.

and another question, how to operate manul focus? measure the
distance by eye only? how to calculate distance, the displacement
from object to film (CCD sensor in this case) or some else. this
is significant for Macro mood.

Hi, anybody has any suggestion about using Manual focus instead of
AF with G3? In what conditions the MF should be used?

In MF mode, if i wanna set the focus distance to infinity, what is
the minimal distance from the lens to the objects in order for the
objects not to blurred. And will the focus length of the lens
affects this distance?

thanks in advance !

--
Ming

--
Ming

 

[Olga Johnson]

Hi, anybody has any suggestion about using Manual focus instead of
AF with G3? In what conditions the MF should be used?

In MF mode, if i wanna set the focus distance to infinity, what is
the minimal distance from the lens to the objects in order for the
objects not to blurred. And will the focus length of the lens
affects this distance?

Take a look at this:

http://forums.dpreview.com/forums/read.asp?forum=1010&message=3988135

• Olga

 

[Olga Johnson]

and another question, how to operate manul focus? measure the
distance by eye only? how to calculate distance, the displacement
from object to film (CCD sensor in this case) or some else. this
is significant for Macro mood.

You measure from subject to lens.

• Olga

 

[Olga Johnson]

For macro, you don't usually need MF as it is not some fast moving
subject and the lighting condition are usually not bad. Beside,
there is focus bracketing in G3 which is designed with macro in
mind.

Focus bracketing in the G3 works only in manual focus and is perfect for macros.

• Olga

 

[Mike Hunt]

For non-macro mode, you guesstimate the distance and since the DOF
of G3(and all digital camera with small CCD) is very deep, you
don't need to be exactly accurate.

The depth of field is only deep with lens set at wide-angle, and with medium to smaller apertures (f5-f8). I think he should study a depth of field chart to determine the hyperfocal distance, which is hwat I think he's after...

 

[gary ng]

I didn't know that it only works in manual focus. That would make it less useful, IMO. As manual focus with all these digital cameras are very cumbersome. The on screen scale is quite rough and the LCD preview is not as good as my ancient 50mm 1.4 macro in terms of judging focus.
May be that is the reason they need bracketing.

Focus bracketing in the G3 works only in manual focus and is
perfect for macros.

• Olga

 

[Olga Johnson]

I didn't know that it only works in manual focus. That would make
it less useful, IMO. As manual focus with all these digital cameras
are very cumbersome. The on screen scale is quite rough and the LCD
preview is not as good as my ancient 50mm 1.4 macro in terms of
judging focus.
May be that is the reason they need bracketing.

Manual focus is definitely only a button away with the G3. First, it takes its cue from what you are pointing to at the time, and then, when the MF button is pressed, it automatically sets the distance to that subject. Presto! MF set!

• Olga

 

[Mike Hunt]

I didn't know that it only works in manual focus. That would make
it less useful, IMO. As manual focus with all these digital cameras
are very cumbersome. The on screen scale is quite rough and the LCD
preview is not as good as my ancient 50mm 1.4 macro in terms of
judging focus.
May be that is the reason they need bracketing.

Manual focus is definitely only a button away with the G3. First,
it takes its cue from what you are pointing to at the time, and
then, when the MF button is pressed, it automatically sets the
distance to that subject. Presto! MF set!

Yes, but I think he was referring to the focus bracketing feature. I'm also surprised to hear that in only works in manual focus moed. I too think that this takes away quite a bit from its usefulness.

No matter how quickly you can get into MF mode, you're still faced with that tiny little screen, inaccurate distance scale, and cumbersome and imprecise focusing control.

Any camera costing this much should really have much better focus control.