«

I am trying to figure out how good the autofocus of this camera is in low
light. The test reports I read often measure the performance with and
without AF assist. In the former case the camera is said to be able to
focus in complete darkness; without it the autofocus is much less
impressive. Apparently its AF assist consists of a flsah strobe. Can anyone
explain what this means and what the disadvantages/limitations are of using
this type of AF assist?

--
Luuk Houwen
Hattingen
Germany

The flash flickers real fast in low light situations. Kind freaky
but it seems to work.

There are different types of systems for assisting autofocus in low-light
situations. On one camera, there is a small white light that will illuminate
the scene for about a half-second. On some of my flash units, there is a dim
red crosshatch pattern that is emitted every second or so while flash operation
is getting ready. On some cameras, it is all done just using the main sensor to
assist what the lens is doing (since most of the autofocus system is inside the
lens).

---Bob Gross---

"Luuk Houwen" <> wrote in message
news:Xns9422A061CD8Flh@62.153.159.134...
> I am trying to figure out how good the autofocus of this camera is in low
> light. The test reports I read often measure the performance with and
> without AF assist. In the former case the camera is said to be able to
> focus in complete darkness; without it the autofocus is much less
> impressive. Apparently its AF assist consists of a flsah strobe. Can anyone
> explain what this means and what the disadvantages/limitations are of using
> this type of AF assist?
>
> --
> Luuk Houwen
> Hattingen
> Germany

I have a 10D, and the built-in AF assist certainly works. (Whether you'd want
to use it is another matter...) It works by firing a short burst of flashes (So
you've got to be in a mode where the flash will be controlled by the camera - I
use the green rectangle idiot mode for this), and the camera finds focus using
its normal sensors. Works fine in the dark cellars of stately homes etc. BUT,
the strobe effect of the flashes is very disturbing, and I far prefer the red
pattern emitted from my 550EX or ST-E2; or as found on some earlier EOS
cameras.

--
M Stewart
Milton Keynes, UK
www.megalith.freeserve.co.uk/oddimage.htm

Thank you all for your answers, which are just what I was looking for.

--
Luuk Houwen
Hattingen
Germany

*Remove NO-JNK from email adress before replying directly*

On Tue, 28 Oct 2003 00:59:08 +0100, Luuk Houwen
<> wrote/replied to:

>I am trying to figure out how good the autofocus of this camera is in low
>light. The test reports I read often measure the performance with and
>without AF assist. In the former case the camera is said to be able to
>focus in complete darkness; without it the autofocus is much less
>impressive. Apparently its AF assist consists of a flsah strobe. Can anyone
>explain what this means and what the disadvantages/limitations are of using
>this type of AF assist?

You can turn off auto focus assist, you won't need it. The 10D has
excellent low light AF. Period.

Believe it or not, it's impossible to focus without light, duh!

So you need some light. But not very much.