Hi..wanna ask whether CAnon 400d has a AF-Assist beam or not like other camera??

I try to use 400D in with flash in low-lighting condition...it will have a intermittent flash for few times when i half press the shutter button....not beaming a light out..

is this call Flash Strobe???like too consuming the battery lo....

Is this normal for every camera..??

Hope u all 400D member can help me out ya..

thankz a lot lot...

http://www.dcresource.com/reviews/canon/di...iew/index.shtml

There isn't any AF assist lamp, it uses the flash strobe as stated above.

Thankz calvin...

but i realise it flashes too many flashes cause more battery consumption lo..

i thought is my camera "sort sort liao"..

@sweesin82


It's normal, dont worry. I prefer those old school days canon film body when they use a separate small lamp to assist in AF. If i'm using an external flash the build in camera flash cant be used in assisting AF.

yaya...i prefer the small lamp oso like in the Nikon Camera..an orange light for the AF-Assit Beam...

wat for using so high flash to assist the AF o....only use in very black environment lo...

if i wanna shoot without flash then how can i use the AF-assist??

Canon does not have flash option le..like nikon got slow sync, red eye (select inside menu only), rear flash and so on....

any opnion on this??

The external flash has AF assist beam right? if using 430ex/580exII

Well, the only alternative you have is to get a small led torch light and attach it to your cam with velcro or something. When you take photos in low light, turn on the small led torch light, and it will help you focus.

yes.. external flash do have their own AF Assist beam, which is patterned in either - or | or + shaped, depending on the focus point that u choose.. so u wun need the built in flash for AF assist purpose..

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Added on July 30, 2007, 10:17 pmi dun think the built in flash in canon have the slowsync, the external flashes has'em..
the red eye and rear flash (2nd curtain) is there, read your manual on how to access them..
there's a small lamp beside your main grip, that lamp will light up when u half-press the shutter for red-eye reduction purposes.

This post has been edited by kevin613: Jul 30 2007, 10:17 PM

The pre-flash will also help reduce red eye if you dont like the stupid flash, try to find yourself an infrared flash light to help AF in low light, your subject wont see anything besides you pointing a "no battery" flash light at them

This post has been edited by AlamakLor: Jul 31 2007, 01:07 AM

The IR flashlight ray can be detected by the camera for AF but not the human eye?

yup, IR can't be detected by eyes, but the camera will see it. Never seen this sort of things in science centre? lol

I never seen it in science center. Which science center? All science center in the world also got?

But you can easily see IR ray by using a digital camera on your mobile phone, turn on the camera, face it to the remote control IR point, and you will be able to see a bring light from the remote when you press a button.

I thought cameras would need a visible light like the light on the D80 to assist in AF. Cause if invisible light ray like IR, how would it be able to illuminate the subject/object you are shooting?

Then how come all AF lamps on camera are bright lit, why don't they just use IR?

This post has been edited by calvin_gsc: Jul 31 2007, 12:45 PM

Just because the light can't be seen by bare eyes doesn't mean the camera can't see it

I suppose why camera manufacturers don't use IR is because IR leds dont have enough intensity compared to xeon bubs. Or at least they cannot insert enough leds in the tiny hole to get adequate intensity.

CCTV is well known to use IR to light up subjects in order to help the camera to focus:

Have you seen any CCTV with big xeon/halogen lamps to help it focus?

Are there any digital camera at all that uses IR for AF?

Any brands or model?

Is CCTV = Digital camera? No right?

We're discussing how it'd help a digital camera right? More specifically in this case, a Canon 400D dslr.

This post has been edited by calvin_gsc: Jul 31 2007, 12:53 PM

I was just giving an example of IR used to help camera sees in the dark without actually illuminating the subject with lights that can be seen by bare eyes. It has nothing to do with whether the camera is digital slr, or digital video cam.

IIRC the canon ex flashes uses IR to AF assist. Some people are very sensitive to pre-flashes *closed eyes before the exposure is made*, using IR to help focus would avoid this sort of problem. You can get an led torch, gut the leds out and replace them with high intensity IR leds

http://www.dpreview.com/learn/?/Glossary/C...ist_lamp_01.htm


This post has been edited by AlamakLor: Jul 31 2007, 01:00 PM

I wonder why they never incorporate IR for AF into the digi cams or external flashes if it's effective. Maybe it's not...

This post has been edited by calvin_gsc: Jul 31 2007, 01:07 PM

laser beam perhaps????

This post has been edited by yewkhuay: Aug 6 2007, 10:50 PM

green laser that can pop baloons?

but wait.. how about a body with an auto-extending tape ruler?

The series of pre-flash are meant not only to be an AF assist but also serves to calculate the proper exposure at the time of a flash during the real exposure. So you get a more accurate exposure when the flash is fired. The pre-flash method has always been Canon's style and if I'm not mistaken its part of E-TTL II. If you're using speedlites like 430EX or 580EX, the pre-flash goes on as well apart from the AF-assist beam.

Its also good to know that pre-flash does not happen all the time (depending on the light meter), so it cannot be treated as a method to reduce red-eye effect. Take note that pre-flash only happens when you half-press the shutter button and not during exposure. Thats when the camera calculates the exposure and perform AF. Further pressing will release the flash and capture the exposure. Using speedlites mounted high above the lens-to-eye axis is a good way to reduce the red-eye effect. Strobe flashes would also help.

I got this information from the EOS Lighting Sytem: Field Guide of 430EX & 580EX. Its a book available at Borders, MPH and KinoKuniya. Hope that helps.

thankz davidmak...

i think ur information is more accurate lo..

luckily is not my 400d problem..