sometimes, even a f1.4 lens !
sometimes, even a f1.4 lens !
Low lighting, a bright object with no visible details on it, a large plain surface or distance between u and yr subject can cause lens to hunt. The latter being slower to focus lock.
Canon EOS 5D, 24-70 f/4 L IS, 50 f/1.2 L, 70-300 f/4-5.6 L IS, 600EX-RT. Sigma 12-24 f/4.5-5.6 EX.
i have tat same problem at times... esp in low light n sometimes when shooting closeup shots.. think i move too close... closer than my min focusing dist..
Trust me, I'm not so bad! | TangShooters
yes, kit often has nothing much to say
just passes snide comments
and ignores comments on his own photography threads
probably has an overly high opinion of himself, been there seen that
some people just have an overblown ego, let it go guys
must say here that it's a very sad existence though, to just troll around and float on clouds which are self-constructed, boohoo
in any case, on topic - it depends on a lot of things, whether the object is moving
whether the object has "contrast"
if you try to af on a white smooth surface even your 20,000 dollar lens will not be able to find anything la
if anything, most people here would vouch that i'm the antithesis of that
i use cheap lenses, and don't really care that much about equipment
AF has nothing to do with equipment, and people are just trying to learn something
understanding one's equipment and its limitations is the key to breaking past all that
so why limit them and paint everyone with the same brush?
i doubt the ts is like that, same goes for most of the ppl who have been posting here
Last edited by eow; 16th October 2007 at 01:29 AM.
头可断，血可流,倩女不可不追求 carpe diem,when in doubt, hoot first,apologise later:p GALLERY
AF works best with lines or some shape. If you have all straight lines, or nothing at all, it's gonna hunt a lot. Find something diagonal, or tilt your camera diagonally for it to lock on, then tilt back - then it will work.
Most AF modules are meant to look for a clear difference in light, contrast or pattern.
If the subject you intend to focus on, does not have a clear difference or has similar patterns all over, then it's hard for the AF module to lock on. Note that sometimes during macro shooting, the lens may also hunt even when the subject has a clear definition and colour. This could be due to the fact that the subject may not be in the AF tracking point during the focusing action.
[+] [+] [+]
Let's say it's dead centre already at the red colour, but when you allow the AF function, the lens on moving back and forth, it may have moved such that the subject may be at the left or right of the focusing point and not make the sensor catch on correctly and make the module keep hunting.
Learn to identify objects and features where you can use to lock focus so that next time, you can be confident of yor focus.
Hope this won't me mis-construed as being unhelpful, but I still prefer a rough ground glass for ultra quick focus, and a split-image for precise focus. AF is a gift of speed and convenience, but not everyone can afford a $6000 or $12000 camera for the best AF. I think the majority bulk of photogs get by (or have to live with) with $1K+ bodies.
AF hunts due to the reasons stated zac08,
just something to add, cameras will also have problem in grey tone(18% if i am not wrong).
Member of the earth
but even with a split prism, without contrast, its going to be a bitch to manual focus since both ends of the prism will show the same thing...
when the camera AF system cannot find something to lock focus on it will hunt for it.
firsty understand what the camera needs to lock focus on
and what it cannot focus on.
the lens is not the main equipment here
but it will help the camera, if it was brighter and more contrasty for the camera AF sensor to "see"
the user manual has this information (illustrated with diagrams)