have I got a dud 350d?

the autofocus on my 350d seems to be quite bad really....I'm not expecting miracles in low light, but see the attachment; first that isn't IMO low enough light for it to be hunting, and second, it said it had found focus on the centre point! (ie. the little beep+red flash)......so wtf?? this is from a very recent trip to Oz and quite a few of my images have ended up like this .


(i've only ran auto levels on this pic)

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My first question is what was the shutter speed? Also what lens are you using?

1/30th, lens was canon EF 28-105mm 3.5-4.5

(lol if it was 0.5s exposure I really wouldn't be asking)

looks like camera shake to me up the shutter speed ,if your at 105 on your zoom try 1/250 sec.
Rob.

if you didn't have that on a tripod, in my experience, thats way to slow to hand hold. I think in highschool they taught us never to handhold under 1/60th. and that was with out a zoom lens, I forget what it is, but the further you zoom in, the faster the shutter speed has to be for you to hand hold, so say if you were at 105mm, you really should be hand holding at speeds greater than 1/60th.

but yah, I'd say the shutter speed of 1/30th was too slow for handholding, and that is probably what happened.

ah crap lol. i WAS at 105, didn't really factor that in......i just thought that getting down to 1/15 or so was tripod country.

damn it to hell.

live and learn now you'll never do it again

xft.y wrote:
the autofocus on my 350d seems to be quite bad really....I'm not expecting miracles in low light, but see the attachment; first that isn't IMO low enough light for it to be hunting, and second, it said it had found focus on the centre point! (ie. the little beep+red flash)......so wtf?? this is from a very recent trip to Oz and quite a few of my images have ended up like this .

It is about vibration, not AF (check the directional blurring of reflection in the eyes)

Yep, for as far as I can make out, it is in focus, but quite motion blurred.

I agree it's camera shake. The rule of thumb I was taught was that when you're shooting hand-held the shutter speed should be 1 divided by the focal length or faster. So for a 100mm lens you need 1/100th of a second, and so on. But that's for 35mm film cameras. With a 350D the crop factor is 1.6 which means your lens behaves like a lens that's 1.6 times longer on a 35mm film camera. So your 105mm zoom behaves like 168mm on a 35mm film camera, and you need a shutter speed of 1/168th or faster - say 1/200th or 1/250th to be safe.

Of course all of this is based on some sort of average person. If you've got a steady grip and you have good technique - legs well planted, arms braced against your body, breathe out before shooting - then you can get away with slower shutter speeds. (But nowhere near 1/15th for a 105mm lens!) Or if you've got shaky hands you need to go for even faster shutter speeds. Try it and see.

I've heard that your shutter speed should be the same/above your focal length, i.e. at 50mm you should be using 1/50th+

Hi

Yes, I agree with the others ~ camera shake. It is possible to hand hold at surprisingly low shutter speeds depending on your age, gender and muscle tone (seriously) but do bear in mind that that relies on the subject being static. If that 'roo or wallaby was chewing (mouth full of food) its head would be in motion and at 1/30 combined with your imperceptible camera shake is the result you see.

HTH

StewartR hit the nail on the head.... don't forget to factor in 1.6x crop (unless you have a FF body). But this is a guideline, not a rule. Some days I feel a bit steadier than others and can shoot up to a stop under the 1/focal length rule (without an aid such as IS), but that's just me.

cheers guys love this place.

lesson no 283975421.....always take the tripod

That's where the 1/efl hand-holding rule of thumb comes in. 1/15 will be generally safe with a 10 mm lens, but as the lens gets longer your shutter speed needs to creep up too.