I'll Join in, just got the 70-200 f4 IS

There have been a lot of threads about people getting a new 70-200. And as a matter of fact, I got one just this past Thursday. So I would feel left out if I didn't make my very own post about my very FIRST L.

So far this lens is amazing, I love the color, the speed and the IS.

My only problem is that it seems to back focus by just a few millimeters. Its not enough to consider it soft(I dont think) but enough that I notice it. What does everyone think?

All shot wide open

*Edit:*Forgot to mention they were handheld! I'm amazed I was able to get the cat sharp at 1/25 handheld. Love the IS!

Back focus a few mm? Hard to tell from these examples. Forget about that and enjoy your great lens !

Looks very good to me. Congrajubilations.

Unloader wrote in post #8400417
There have been a lot of threads about people getting a new 70-200. And as a matter of fact, I got one just this past Thursday. So I would feel left out if I didn't make my very own post about my very FIRST L.

So far this lens is amazing, I love the color, the speed and the IS.

My only problem is that it seems to back focus by just a few millimeters. Its not enough to consider it soft(I dont think) but enough that I notice it. What does everyone think?

All shot wide open

1/25sec 800is 165mm f4

100% Crop


1/200sec 100iso 200mm f4

100% Crop

this lens is known to slightly mis-focus at MFD. i hope you're not saying the focus is off on the orange tabby .

ed rader

Wow, I love this forum! Quick responses and friendly!

I think some of my "back focus" is from user error. The tabby was one of my better photos in terms of focus, despite the 800iso adding noise.

I have done some controlled tests, just for fun, and this lens seems to be on par with my copy of the 50 1.8(very sharp). The 50 edges it out just a bit(at f4), and most likely due to the MFD as you said, ed.

Anyway, all in all I am extremely happy with my purchase, and it really is a joy to use. I know where ever I point my focus point, it will do just that. And its scary how well it focuses in low light!

I confess, I am a pixel peeper, I wish I could change that, but I can't.

best regards,
Michael

Its not the sharpest zoom on the planet for nothing. I hope that one day Canon takes the AF system and sharpness of this lens and puts it into their entire line. It really is a technological marvel.

I shoot with mine a lot, especially when going to sporting events (NFL, MLB, NHL, Pro Tennis (WTA/WTP)), and I find that my keeper rate for sharpness exceeds 95%, I end up with so many choices of keepers the average 1800-2000 shots from the day take me a week to go thru. Honestly, its a problem I am happy to contend with.

Nice truck...bad ass front end to be sure.

ed rader wrote in post #8400455
this lens is known to slightly mis-focus at MFD. i hope you're not saying the focus is off on the orange tabby .

ed rader

Reviving this thread, I just got a used ƒ4 IS, and noticed some back focusing, apparent at the 70mm end, and at near MFD. There does not seem to be a problem at 100mm upwards. So, here are a few questions I have that I was hoping someone could help set my mind at ease:

Could the AF sensor size and location on my camera not be exactly as marked on the screen? That could explain why at the longer FLs, with the subject larger and more distinct in the frame, the AF sensor does not make a mistake?

And Ed, could you point me towards more information about this slight misfocus at MFD issue? How bad is it? How prevalent is it?

Should I be worried, or should I just go out and shoot more and enjoy the lens?

Such a handsome Beast!

<grin>

Looks pretty dang sharp to me. Congrats on your new lens. It is one of the best.