night time autofocus problem

[horhe]

Hello guys, I have a problem on auto focus at night (night portrait). my canon 400D seems cann't focus. the flash is firing and trying to focus but not successful. My last option is to switch to manual focus but often quite blured (not perfectly focused). I was using the kit lens. Any advice?

[CYRN]

Are you trying to shoot portraits at night?

How far is your subject from you?

Is the subject moving or staying still?

[horhe]

I incur the problem regardless whether the target is moving or at still. just trying to get pictures during night outing w/ frens. Distance of about 2-4 meters. Though there are times it can focus but quite rarely. The reason when i go out at night, id rather bring my digicam with me not my SLR. Im looking forward of using a better lens.

[CYRN]

OIC. A few more question...

which mode is your 400D on?

Did the 400D actually capture a shot?

What's the exposure time/settings?

[horhe]

i used AF mode. set the ISO to max 1600. Max aperture too. I guess the lens is not good enough for night shoot.

[CYRN]

I mean which mode as in P,S,A,M or "green box" or whatever is your setting of the dial on the top right of the cam?

Or why not you post a couple of sample pics the we can better appreciate the situation. As least can analyze the exif and see what's actually wrong.

[Octarine]

Originally Posted by horhe Hello guys, I have a problem on auto focus at night (night portrait). my canon 400D seems cann't focus. the flash is firing and trying to focus but not successful. My last option is to switch to manual focus but often quite blured (not perfectly focused). I was using the kit lens. Any advice?

That's normal for low light conditions. The Autofocus needs a certain amount of contrast in the picture to adjust. If there is not enough light the AF cannot focus properly and starts 'hunting'.
What you could do:
1) Define one focus point (see manual of cam) and aim this point at a contrasty area of subject (lines, edges where dark and bright areas meet), recompose and shoot.
2) After AF got the correct distance you can switch to MF to keep the setting. Then you can recompose / rearrange your shoot. Bear in mind the Depth of Field, especially with large aperture and portrait shoots. Don't change the distance to subject accidentally.
3) Use external flash with red light AF support. This red light is more accurate and focus locks better in low light conditions.
Your lens can do night shoots, no issue. You just need to work around the limitations. Using high ISO will only produce more noise in the picture but will NOT help you to focus because focusing is NOT done by the image processor. Use ISO to increase the shutter speed or / and to lower aperture. Try not to use largest aperture. I suggest using Av mode instead, gives you more control over the cam settings.

[horhe]

Thaks Octarine, very infomative and helpful especially your 1st two suggestions. I used to use high ISO during night to increase shutter speed. Will try to play around.

[icebox]

The kit lens may hunt a bit in low light, but it should be able to lock into focus, unless the subject is in really low light or low contrast. Did you use the center focus point to focus? It's more sensitive.

[night86mare]

if there is not enough light to focus, it cannot focus. maybe can, but will take very long after many tries.

some cameras will use popup flash to send out some light for you to focus accurately.

alternatively, you can always light up your subject's face with a torchlight to attain focus, then change to manual, shoot on tripod, and subject don't move too much.

[Simon_84]

you can ask your friend to use an led white light to lit his/her face from beneath the neck, of cos not directly shine onto.

[All Blue]

are you shooting in a very dark environment? i faced the same problem too with night portrait, esp if the subject is infront of some trees. you have to have a contrast in order for the AF to work. it's good that the subject wears light color clothing with a dark background. alternatively move to a brighter location or if someone has a lighter, it can come in handy just to light up the face.

[turtle76]

Actually I got the same problem with my 400D also. Cant really focus when I am shooting indoors where lighting is a bit dim. But coz one reason I guess could be I am using the 18-55 kit lens which most people say is quite useless.

My previous Nikon D60 didn't give me that problem though even with the standard kit lens. Hmmm... dunno is coz photographer lousy or lens/ body lousy

[Simon_84]

Originally Posted by turtle76 Actually I got the same problem with my 400D also. Cant really focus when I am shooting indoors where lighting is a bit dim. But coz one reason I guess could be I am using the 18-55 kit lens which most people say is quite useless. My previous Nikon D60 didn't give me that problem though even with the standard kit lens. Hmmm... dunno is coz photographer lousy or lens/ body lousy

you can go read the user reviews of 400d in dpreview...think 350d/400d also have some minor problem focusing in low light.
i believe there's nothing wrong in the cam body since 400d has the best iso performance around for 10mp entry lvl cams.

maybe you might wanna change your kit lens to the new 18-55mm IS and see if the performance is better ?
but i do heard before canon kit lens lens really is crap compared to nikon's kit lens.

nikon has af-beam assist so low light focusing is not much of a problem.

[turtle76]

Originally Posted by Simon_84 you can go read the user reviews of 400d in dpreview...think 350d/400d also have some minor problem focusing in low light. i believe there's nothing wrong in the cam body since 400d has the best iso performance around for 10mp entry lvl cams. maybe you might wanna change your kit lens to the new 18-55mm IS and see if the performance is better ? but i do heard before canon kit lens lens really is crap compared to nikon's kit lens. nikon has af-beam assist so low light focusing is not much of a problem.

I didn't even on the AF assist for my Nikon still can auto focus...

On my 400D the lens just go in & out, in & out till i give up. Not to mention the Canon's af assist cant be used if you are shooting animals at close distance. It will blind my cat if it is on...

Anybody got any good lens to recommend for 400D thats gd for night shots?

[Simon_84]

Originally Posted by turtle76 I didn't even on the AF assist for my Nikon still can auto focus... On my 400D the lens just go in & out, in & out till i give up. Not to mention the Canon's af assist cant be used if you are shooting animals at close distance. It will blind my cat if it is on... Anybody got any good lens to recommend for 400D thats gd for night shots?

may you can use a piece of tissue paper cover the flash ?
you can try the canon 50mm f1.8 or f1.4 for starters.
more ex low light lens would be tarmon 17-50mm f2.8 or sigma 30mm f1.4

[turtle76]

Originally Posted by Simon_84 may you can use a piece of tissue paper cover the flash ? you can try the canon 50mm f1.8 or f1.4 for starters. more ex low light lens would be tarmon 17-50mm f2.8 or sigma 30mm f1.4

I have got a 50mm f1.8 also cant focus if it just gets slightly darker at home. I put on a flash diffuser but the assist beam still too strong. If only someone got a Tamron 17-50mm for me to try. V tempted to sell off and change to another cam liao...

[Simon_84]

Originally Posted by turtle76 I have got a 50mm f1.8 also cant focus if it just gets slightly darker at home. I put on a flash diffuser but the assist beam still too strong. If only someone got a Tamron 17-50mm for me to try. V tempted to sell off and change to another cam liao...

dont tell me you wanna change to some other brand of cam instead ?
actually i feel a bit itchy to change to canon but after hearing the low light focusing problem...change my mind, keep faith with my nikon.

[turtle76]

Originally Posted by Simon_84 dont tell me you wanna change to some other brand of cam instead ? actually i feel a bit itchy to change to canon but after hearing the low light focusing problem...change my mind, keep faith with my nikon.

Haha spot on. Think change back to Nikon or try out Fuji/ Sony. Since I have yet invested in lens so not so painful for wallet...

But then Canon has biggest resale mkt so thats one major consideration too.

Yest nite I tried turn on all the lights in my house, attach a flash and try to take some shots using the kit lens without the AF assist. And best part? Got external flash also no use coz I cant even fire it when the lens cant even focus !! Somebody kill me...

[Simon_84]

Originally Posted by turtle76 Haha spot on. Think change back to Nikon or try out Fuji/ Sony. Since I have yet invested in lens so not so painful for wallet... But then Canon has biggest resale mkt so thats one major consideration too. Yest nite I tried turn on all the lights in my house, attach a flash and try to take some shots using the kit lens without the AF assist. And best part? Got external flash also no use coz I cant even fire it when the lens cant even focus !! Somebody kill me...

sony has more noise issues than nikon so gd luck then.
actually if you post this in the canon section...i get that feeling that they gonna say something along the lines that you dont understand your cam well enough.
did you up your canon iso settings to 400 or 800 ???

i dont care about the general resale market...to me most importantly is all-round use and user-friendly cam...
if you want faster focusing, you can try the d80 with 50mm f1.8, go loan one set to test first for 1 or 2 days before buying.
or maybe loaning a cheaper set like d50 (may have slower focusing than d80) with 50mm f1.8 also allows you more options as well.