December 18, 2014, 10:39:22 PM

Author Topic: focusing accuracy/repeatability on 50mm  (Read 1392 times)

CharlieB

  • Canon 70D
  • ****
  • Posts: 302
    • View Profile
focusing accuracy/repeatability on 50mm
« on: October 30, 2012, 07:54:38 PM »
I'm not all that thrilled with the focusing accuracy or  of the 50mm f/1.4 USM.
I tend to shoot that lens at about f/2.0 most of time.  Closed just enough to control the creaminess at f/1.4.
And its a tough thing to get it to focus where I like. 

So the question is - does the 50mm f/1.2L do any better with focus?  I'd probably be shooting it wide open, or just a hair closed as well.

Thanks for the input!~

canon rumors FORUM

focusing accuracy/repeatability on 50mm
« on: October 30, 2012, 07:54:38 PM »

Mt Spokane Photography

  • EF 50mm F 0.7 IS
  • ***********
  • Posts: 9371
    • View Profile
Re: focusing accuracy/repeatability on 50mm
« Reply #1 on: October 30, 2012, 08:37:46 PM »
The body is much more responsible for repeatability than the lens.  The 5D MK III and the 1DX are much better than older models.  Generally, the more expensive lenses are better, but there are exceptions.

neuroanatomist

  • CR GEEK
  • ************
  • Posts: 15198
    • View Profile
Re: focusing accuracy/repeatability on 50mm
« Reply #2 on: October 30, 2012, 09:34:42 PM »
Did you AFMA the lens, and if so, how?

The 50L has some focus shift - backfocus when stopped down a bit with a close subject (not an issue wide open). 
EOS 1D X, EOS M, and lots of lenses
______________________________
Flickr | TDP Profile/Gear List

RLPhoto

  • Canon EF 300mm f/2.8L IS II
  • ********
  • Posts: 3543
  • Gear doesn't matter, Just a Matter of Convenience.
    • View Profile
    • My Portfolio
Re: focusing accuracy/repeatability on 50mm
« Reply #3 on: October 30, 2012, 10:04:37 PM »
I'm not all that thrilled with the focusing accuracy or  of the 50mm f/1.4 USM.
I tend to shoot that lens at about f/2.0 most of time.  Closed just enough to control the creaminess at f/1.4.
And its a tough thing to get it to focus where I like. 

So the question is - does the 50mm f/1.2L do any better with focus?  I'd probably be shooting it wide open, or just a hair closed as well.

Thanks for the input!~

When shooting the 50L at f1.2 on the 5D3, it's pretty sweet. I still take plenty of shots and pick out the best because more than likely its your breathing that will move it out of focus at 1.2.

Just take more photos.

CharlieB

  • Canon 70D
  • ****
  • Posts: 302
    • View Profile
Re: focusing accuracy/repeatability on 50mm
« Reply #4 on: October 31, 2012, 12:27:50 AM »
Oh yah, I've AFMA'd the 50/1.4 on the 5DmarkII, and the new 7D. 

One is -6 the other -5.  Thats ok, they're linear... full moon to close up at f/2.0 both bodies track well with the lens.

The problem - is - three shots, from a tripod, from infinity backward to focus, give three different points of focus.  The repeatability of both of the 50/1.4's I've owned was not good.  They do ok at about f/2.8 or so.. but wider.... and wide open... its maybe 1/3 to 1/2 the shots are not where they ought to be.  They run in front, and behind,  so its not AFMA.... it simple inconsistency. 

AFMA on over two hundred shots in each body.... in real world conditions at various distances from "full moon in the sky" to about 1 meter.   Thinks get very weird in that 25 foot range... do better at longer and closer distances, but still... its 1/3 to 1/2 that are not in focus.

canon rumors FORUM

Re: focusing accuracy/repeatability on 50mm
« Reply #4 on: October 31, 2012, 12:27:50 AM »