Canon 7 point AF and A-DEP

[myloplex]

Advice please

1) when to use A-DEP mode ?
group photos ? taking an object to 'stand out' against the background ?

Also, when you press the A-Dep button near the lense release, the image in the viewfinder turns dark at times. The darker the better ?

Can the A-DEP button be used in other creative modes ?


2) 7 point AF ?
The point that flashes means focus is achieved.

Lets say you got 3 people sitting side by side.
AF flashes for center person's face. How to get all 3 faces sharp then ?

 

[StreetShooter]

Advice please

1) when to use A-DEP mode ?
group photos ? taking an object to 'stand out' against the background ?

Also, when you press the A-Dep button near the lense release, the image in the viewfinder turns dark at times. The darker the better ?

Can the A-DEP button be used in other creative modes ?


2) 7 point AF ?
The point that flashes means focus is achieved.

Lets say you got 3 people sitting side by side.
AF flashes for center person's face. How to get all 3 faces sharp then ?

Please read the manual.

A-DEP mode will automatically select the ideal aperture to ensure that all the elements in the photo will be in focus (ie all the AF points are in focus). This usually means a very small aperture, which usually means a very slow (and probably unuseable) shutter speed (except in bright sunlight). For this reason, I do not use A-DEP mode. If I want to ensure sufficient DOF, I just use a small aperture in Av mode.

The button near the lens release is the DOF preview button. It allows you to see what the DOF will look like when the picture is taken (which is different from what you see through the viewfinder, unless you are shooting wide open). If you have stopped down the aperture, the viewfinder will darken (because less light is coming through) but more of the picture will be in focus (ie there will be greater DOF).

For situation (2), I would suggest you use the green box mode and just take the picture.

 

[cheechee]

Advice please

2) 7 point AF ?
The point that flashes means focus is achieved.

Lets say you got 3 people sitting side by side.
AF flashes for center person's face. How to get all 3 faces sharp then ?

Well, if they are really sitting side by side, and the af locks on the center person's face, aint it be sharp on all 3 faces? as they are same distance from you?

 

[mervlam]

Use your eyes to see if the 3 guys are in focus... DUH.... as simple as that.

if not, play around with the aperature and press the DOF button and check for focus again.

 

[coca88]

Hmm .. for me i am unable to see whether the person on the left and right is focussed on the viewfinder. As a general rule of thumb , when in doubt , I would tend to use f8 .. :embrass:

 

[myloplex]

Hmm .. for me i am unable to see whether the person on the left and right is focussed on the viewfinder. As a general rule of thumb , when in doubt , I would tend to use f8 .. :embrass:

you the most helpful
how come f8 ? Tot 5.6 ?

Is there any general rule of thumb for the below ?

Group --> A-DEP else f.8
Landscape --> f22 ?
Portrait --> f 5.6 ?
Macro --> f 2.8 ?

 

[coca88]

I've tried shooting at 5.6 and 8 .. and compared them . So far , the shots at f8 have been rather sharp from end to end . At 5.6 the shots are close but still there are areas which is will not be focussed sharply

Just a personal comment , the decision on whether to shoot at 5.6 or 8.0 will also have to be determined by how far apart the subjects are

 

[myloplex]

I've tried shooting at 5.6 and 8 .. and compared them . So far , the shots at f8 have been rather sharp from end to end . At 5.6 the shots are close but still there are areas which is will not be focussed sharply

Just a personal comment , the decision on whether to shoot at 5.6 or 8.0 will also have to be determined by how far apart the subjects are

the rest leh ? landscape ...etc ... got comments ?

 

[Tweek]

the rest leh ? landscape ...etc ... got comments ?

i give u the best rule of thumb: shoot everything in f22. guarantee plus chop all will be sharp.

 

[myloplex]

i give u the best rule of thumb: shoot everything in f22. guarantee plus chop all will be sharp.

yeah ! if I have stadium flood lights as my external flash .. .i can shoot at f 91 ya !

 

[Bluestrike]

From Roy's tread
http://forums.clubsnap.org/showthread.php?t=42798
we can see that what the DOF will be when using what kind of aperature etc etc etc.

Take a look.