Focus confirmation light in Manual Focus mode?

Hi,

I am trying to quit using AF and rely on MF instead. I apologize for my ignorance but I thought the focus confirmation

light only works in AF mode. Why then I see it in MF mode? Not all the time though. Sometimes it lights and the

beep goes off, other times it does not.

Thanks

It goes off during manual focus when correct focus is achieved at the active focus point.

Actually, that should read it goes on (meaning the focus indicator lights up) and the beep goes off when correct focus is achieved.

<p>The AF sensors work whether the lens is in AF or MF; the difference is that in MF the body doesn't tell the lens' focus motor what to do. The manual for my body (which I won't name since you didn't name yours) does mention that the focus confirmation light can come on even when the lens is in MF mode.</p>

It only works for Canon EF(s) series lenses though. The AF conformation light does not come on when using manual focus lenses via an adapter unless the adapter contains the correct electrical circuitry and contacts to fool the camera into thinking an EF(s) lens is mounted.

My camera is 30D. Something doesn't make sense. The Manual says that if I press shutter 1/2 way during MF, then

AF becomes engaged. This is clear. The focus lock is achieved this way in AF mode and thus focus confirmation.

But focus lock is not needed with MF, right? After all, we turn the ring to achieve the focus. So, all I have to do after

focusing manually is to just press Shutter all the way once.

WHAT IS THE ROLE OF THE FOCUS CONFIRMATION LIGHT THEN? It drives me crazy, sorry.

<i> WHAT IS THE ROLE OF THE FOCUS CONFIRMATION LIGHT THEN? </i><br><br>Well, the camera tells you that you have manually set the focus point/plane to that part of the image... It is FYI only (I find it beneficial 'cos MF on crop bodies w/o LV sucks bug time so I'll take all help...)

Indeed it is FYI only. One instance where I find it comes in handy is when I'm shooting macro, I've got MF set and I've set magnification with the focus ring, and then I rock the lens back and forth to achieve focus.

 

BTW if you don't like the beeping you should be able to turn it off somewhere in your camera's menu. You'll still get AF points lighting up in the viewfinder.

Hi Oleg,

 

I have two 30D and a 10D backup camera.

 

If you can "quit AF" and manually focus accurately with any of the 1.6X crop cameras, you are far a better man than me.

 

The viewfinder on all crop sensor cameras, along with the focus screens they use, are simply not very conducive to manual focus. Too small, not focus assist features (NoteL third party screens with split image finders, diaprisms, etc. are available that might help, but they usually dim the viewfinder slightly and, perhaps more importantly, can have some effect on certain metering modes, especially spot metering).

 

I usually use Custom Function 4 to switch AF to the * button, along with the center focus point, and that's just like manual focusing, but a lot more accurate than I can manage actually focusing the lens manually on these cameras.

 

So, my routine is to half-press the shutter button for meter reading and to activate IS if I'm using a lens with it, then position the center point over the subject, press * with my thumb to achieve focus, then recompose as I wish and take the shot. With practice, it becomes second nature and quicker than actually manually focusing the lens. But mainly, it's a darned site more accurate than manually focusing.

 

I do this with both One Shot and AI Servo. Works great!

 

Sometimes with moving subjects I'll either use a different focus point or pre-focus on a point where I know they will be passing (both of which only work if the movement is predictable), or track with the center AF point and change composition later with a crop, if I wish.