50 1.4 Hunting too much

[Sean-Mcr]

Hiya,



My first post, one of many i hopeJ



I’ve just bought a 50 1.4 and I’m having an issue with how much hunting the lens is doing.

It just can’t be normal, I’m sure there’s a fault with it.


Broad daylight the other day I could not for the life of me get it to focus on my partner using af from maybe 4 feet away.

Then later that day, it would focus on a subject and when I returned to focus on the same subject it could just not manage it and the was at varying distences. It was in a well lit room well enough for the kit lens to make focus so the 50 should have walked it

What I also found was that once it attained focus, it managed focus with af every time around my lounge . But then if it missed once then it would miss most of what I’d just been hitting first time just seconds before…

I’m using it on a 20D but can’t be the body has my 85 1.8 and 16-35 just don’t miss like that.

Anybody else come across this behaviour with the lens?



Thanks



(great forum)



Sean

[Dante King]

Hummmm.....did you try cleaning the lens contact points?

[Sean-Mcr]

Well i can't say i have as it's almost out of the box

[Jon Foster]

I'm sure you've checked but is there anything on the lens like a smudge that may be messing it up? My 50mm 1.4 is very quick to get focus and keep it.

Jon.

[Dante King]

That is really odd as my 1.4 is quite quick to focus and keep it as well. what has gone on with this? anything to report?

[Sean-Mcr]

Ok fellas, could you do me a favour please?. I think the problem lies with the Closest focusing distance: 0.45m / 1.5ft

I can't get af anywhere near 1.5ft

I'm in good light here with contrasty subjects so it just has to be a fault with the lens. Could you take some shots around the closest focusing distance and post some results and let me know how often you mange af...


Thanks fellas

Sean

[Dante King]

Regardless of what we can post, the lens should be able to focus about 1.5 feet form subject. I think you need to take it back and get another copy or try out another copy in store. how is it form 3 feet? I will try to make some shots but it might be a while.

[J Rabin]

Sean:
Assuming there is no functional defect with lens, this is a KNOWN "feature" of this lens. Despite the accolades this lens gets on the forum, it is does not have Canon's Ring USM focus motor. It focuses fairly slow. And it hits and misses ON LOW CONTRAST SUBJECTS. A lot of people just use it in single shot drive mode, press the shutter half-way, and finish focusing manually with finger on the shutter. That's the purpose of Canon's FT-M. So, this lens becomes a keeper for settings like a studio, or posing subjects where you have time. For fast paced event photography.... it's not really that functional unless contrast is high, even though it is "low-light lens." The f/1.4 provide a brighter viewfinder for manually focusing. It's the f/1.4 creative DoF and sharpness for moderate price people are buying here, it's not a great lens on its own.
See if it auto focuses on high contrast subjects in good light. If so, it's just "THE WEAK FEATURE" syndrome you've encountered. If it doesn't then it may be faulty.
I sold mine in frsutration because I did not have time to manual focus at evens. Bought the 24-70L. I will add the 85 f1.8 for low light soon, because it DOES have Ring USM. But, even there it will hunt on low contrast/low light. Do not despair. I do a lot of macro. You want to see focus hunting....Jack

[Sean-Mcr]

The thing is it's happend out in broad daylight and in various conditions


This shot i had to get quite a distance (15 to 20ft) before it would focus and it was a pretty nice day, good light ect. I would blame it on the ring usm but hits almost everytime once you're well out of the min focus distance and i mean well out


But it does have the habbit of once it misses something it goes in to miss mode:confused:

[Kennymc]

No problem with mine even in my dark office with the blind drawn... too dark to hand hold 1/3 sec at ISO 1600 and I don't have my tripod with me but it still snaps into focus without hunting...

[Tom W]

The thing is it's happend out in broad daylight and in various conditions


This shot i had to get quite a distance (15 to 20ft) before it would focus and it was a pretty nice day, good light ect. I would blame it on the ring usm but hits almost everytime once you're well out of the min focus distance and i mean well out


But it does have the habbit of once it misses something it goes in to miss mode:confused:

Sean - it sounds like you may have a defective 50 to me. Mine has no such problems, nor did my 50/1.8 when I had it. The 50/1.4 is not as slick-operating as true ring-type USM, but it focuses pretty quickly, even in relatively poor lighting, at any distance from min to infinity. Yours should do the same.

You probably should contact Canon, or trade it for another copy if you just bought it new.

[Tom W]

Here's one I just fired off real quick:

http://www.pbase.com/photosbytom/image/42792680.jpg

The camera focused quickly, with just a quick foreward/back movement. No problems.

[Sean-Mcr]

Thanks Tom, and the rest you the guys

I took it back yesterday and tested it against another and it was faulty, so they replaced it on spot, but i never wanted the display so i'll collect a new one tue.

Thanks for all the feedback;)

Makes me a little more at ease with paying more in store now i have to say..

[Dante King]

Alright! Way to go. Your gonna love this gem!