Lens Focussing Issues

Birty

Suspended / Banned
Messages
350
Name
James
Edit My Images
Yes
I think I am having some problems with my lens :shrug:

I was taking pics at my sons ice hockey game this weekend, and found my lens was re-focusing ALL the time, and made me miss some actions shots whilst it was re-focussing rather than getting the shot I was going for.

My lens is a Sigma 70-300mm DG Macro Lens, so granted, its not f2.8 or a super fast lens but it has served me well, (given its all I can afford at the moment), without any of these focussing problems.

I just wondered if anyone else has had any problems like this before and if so, what anyone did about it ?? :help:

Thanks
 
I suspect there is nothing wrong with the lens, but the amount of light was too low for a lens of that maximum aperture to focus accurately. Also, it isn't going to focus as fast as an HSM or USM lens even if it did manage to lock on to the subject.

People often lust after high-end lenses and bodies when the actual results may not reflect the price differential, but in difficult shooting conditions such as indoor sports, specialist equipment is required.

I suspect a 135L f/2.0 would do a good job if it had enough reach for you. It would be even better for tracking moving objects on a 1D body. Failing that we are into thousands of pounds territory :(.

Phil
 
Last edited:
Did you accidentally turn it into MACRO mode (short focusing distance)?
 
I am going through the same thing I had the camera self clean itself and nothing please advise me what I can do
 
If AF is a problem switch to manual.
 
Did you accidentally turn it into MACRO mode (short focusing distance)?
I have checked this and no, it was on "normal"

Had you accidently switched to AI Servo? This is designed for rapidly moving subjects and gives lots of refocussing. Done this myself before now and your symptoms sound similar
It is on Al Servo but I think this is what I have always used for Ice Hockey, should it be another setting ???

If AF is a problem switch to manual.
MANUAL ?? :gag: :thinking:

I suspect there is nothing wrong with the lens, but the amount of light was too low for a lens of that maximum aperture to focus accurately. Also, it isn't going to focus as fast as an HSM or USM lens even if it did manage to lock on to the subject. Phil
But I have had some good results with this lens, just seems to have started this weekend, I have shot 2 games this weekend and its seems to be doing this more than it ever has before :shrug:
 
But I have had some good results with this lens, just seems to have started this weekend, I have shot 2 games this weekend and its seems to be doing this more than it ever has before

Does it block the shutter button?
 
Been out playing with my new 17-50 tamron f2.8 and found it to be hunting for focus as well. Most of the time its when its getting dark or night time shots. i guess there needs to be enough light for the lens to find a focus point otherwise use manual focus for longer exposures?
 
I have the Sigma 70-300 in the APO version that I use with a 40D. It is very bad for hunting focus in low light even with a static subject, worse with a fast moving subject. Ice hockey being a bit of a melee sport from what I've seen, it's not going to be the easiest sport for any lens.

Tips to minimise the problem..
  • You are shooting over any protective barrier? if not you'll need to be within 3' of the barrier so that the camera/lens doesn't "see" it. If the barrier is beyond the minimum focussing distance of the lens it could be hunting between the barrier and the action;
  • Use the centre focus point only, it's the most sensitive. Don't use multiple focus points as the camera will also be hunting to find the closest part of the action.
  • Consider pre-focussing on an area and letting the action come into the frame. Back-button focus could help with this.

Has the lighting at the rink been constant? Or is it possible that to economise the rink is now using less light (or needs to change some bulbs?). You should be able to check the exif and see if you're average exposure has changed. I'd investigate any change in external factors that could affect the lens performance first, before suspecting a problem with the lens.
 
may sound a silly question but what is back button focussing?

You switch the autofocus activation away from the shutter button half-press to using your thumb on a button on the back of the camera. It sounds like an odd thing to do, but once you get used to it I don't think anyone would go back to half-press.

It's a menu option with some Canon bodies.

Amongst other things it allows you to seperate the exposure lock from the focus lock. And it means you can effectively change from one-shot to continuous/servo focus on the fly.
 
Thanks again for the advice guys, I am just going to another game, will try all the sugesstions and let you know later :thumbs:
 
Been out with the 17-50 tamron 2.8 again and find the focus hunting alot in low light. Generally using apeture priority and have been uping the iso but still finding it hunting alot and not finding focus. can switch to manual focus but had hoped this would be a good low light lens...any tips

sorry for the slight hijack
 
Last edited:
Not really, nothing you can set on the camera will change how well it AF's with any particular lens (other than continuous vs. static) and a lot of cameras AF systems work at a max of f/5.6 so using faster lenses doesn't really help.

I'm not familiar with Canon AF systems but I would imagine the 30D has quite an old system so may not work the best in low light and may be limited to f/5.6.
 
Last edited:
I got one of these and it worked fine for 8 months then it kept stop working and I would have to undo lenes, sent it back as it was still under gar. come back with same problem. Just takes up space at moment cause I cant rely on it to work, missed lots of shots.
Barry
 
Back
Top