I'm beginning to hate my 28-135mm

[ga_shooter]

I have a kit lens, Cannon 28-135mm that has some macro capabilities. In theory its a great all around lens. However I have been having a really hard time getting all the focus points to light up on my 30D. Even in Auto focus it gets it right about 1 out of every 16 tries. Does this sound right? I know its a slow lens, but shouldn't i be able to get better results?
I am wondering if i should send it in to be fixed, of course if the problem is me that won't help at all...
These shots are right out of the camera, with just the WB adjusted. How do they look to you guys? I realize they are small, you can see bigger images on flickr.

 

[DSLR noob]

I know that if I use my teacher's 20D with it's 18-55 kit compaired to my XT's 18-55 kit mine autofocus much faster and much much more accurately. I have heard Canon makes some kit quality lenses in "good batches" and "bad batches". Let's hope you didn't get a bad batch. Also are you going by final picture or viewfinder image? You'd be surprised how many people have a wrong di-opter setting for their eyes. A test to fix this would be to set the center AF point mount the camera on a tripod(or secure it really well), look at a sheet of white paper on a black background, autofocus on the line of contrast and look at the LCD. If it appears perfect, adjust your diopter until the line is as fine as can be in your viewfinder. this might be a fix to your accuracy problem, but shouldn't have anything to do with the speed of AF.

 

[Iron Flatline]

I only ever use a single center focus point. I find the multiple focus points get in my way.

 

[ga_shooter]

I know that if I use my teacher's 20D with it's 18-55 kit compaired to my XT's 18-55 kit mine autofocus much faster and much much more accurately. I have heard Canon makes some kit quality lenses in "good batches" and "bad batches". Let's hope you didn't get a bad batch. Also are you going by final picture or viewfinder image? You'd be surprised how many people have a wrong di-opter setting for their eyes. A test to fix this would be to set the center AF point mount the camera on a tripod(or secure it really well), look at a sheet of white paper on a black background, autofocus on the line of contrast and look at the LCD. If it appears perfect, adjust your diopter until the line is as fine as can be in your viewfinder. this might be a fix to your accuracy problem, but shouldn't have anything to do with the speed of AF.

Ok, its late, but i am going to do this first thing in the morning. Thanks for the advice. If i have a bad batch lens i am sure that canon will do right by me!

 

[ga_shooter]

I only ever use a single center focus point. I find the multiple focus points get in my way.

Really? What do you shoot most often, landscapes or people?

 

[Sideburns]

Really? What do you shoot most often, landscapes or people?

I do it as well. You only really need one focus point anyways...

Just hold it half way on what you are focusing on...until it locks in focus. Then you can frame the shot however you want.

It's much faster, and it doesn't have to guess what you're focusing on.

 

[DSLR noob]

Custom function #4 is a savior. AE Lock /AF lock. You push * to autofocus and then hold the shutter button halfway to get your exposure, compose as you like and shoot. Saves a load of shutter release time if you are going to be shooting a subject that doesn't need refocusing between shots. With this technique, you really DO only need 1 AF point.

 

[soylentgreen]

Unless I shoot a flat wall, I have never got all of the focus points to light up. I just generally use selective focus to compose my images. On rounded objects like you are taking, the DOF may prevent all of the points from focusing. The slight angle of the nameplate may also be doing the same. Like Iron, I use the center point and go from there.

 

[Garbz]

Single shot or continuous servo. I've never been able to get a single shot autofocus picture sharp without tripod and still subject. When macroing I always reach for the manual focus and sometimes CS autofocus.

 

[ga_shooter]

Ok, I get that its not necessary to get what i am looking for. I was out this morning with me 10-22mm shooting landscapes though, and it focused sharp from edge to edge!

 

[The Phototron]

Cause wider lens have more death of field.

 

[sabbath999]

I don't have a Canon, but i can tell you I only use a single focus point as well... I shoot mostly critters and sports, many times they are quickly moving.

Also, when shooting macro, I ALWAYS focus manually...

AutoFocus/AutoExposure locks are my best friend.

 

[Jon, The Elder]

Believe me.....it's not the lens. Using all the focus points to what purpose? We live in 3 dimensions.

 

[TCimages]

+1 on the center focus point shooter. I learned this the hard way. The only time I change it is when I take a lot of portrait style images. For some silly reason, I tend to not frame my subject right when I use center focus in portrait.
I switch between the focus modes too, but the one shot mode is the best way to reframe your shots. This isn't possible in the other modes unless you lock the focus.

 

[soylentgreen]

I am sorry to tell you, that if its edge to edge sharpness you are after, very few slr lenses can accomplish this if at all. Especially on rounded images. If you look closely at the landscape, only a select few objects on the focal plane is actually in focus, the rest is out of focus due to depth of field. Having all points light up is not a true testiment to focus anyway. What you want is to highlight the point of interest in your composition. No? As for a nice sharp lens, look into the L line of lenses. A nice macro like the EF 180 f/3.5 L is crazy sharp from corner to corner. Granted DOF is paper thin but everything within it will be tack on sharp. :mrgreen: Leica makes some really sharp lenses for panoramas that are quite impressive.