Having problem diagnosing issue with 35mm F2 IS

Brand new lens picked up just yesterday. Testing on 6Dii body. The image is blurry when subject is about 10-15 feet away at f/2 and f/2.8, improves a bit when lens is closed down beyond that. I've confirmed AF point with DPP software, but lens doesn't appear to be front or back focusing as NOTHING is in focus, the entire image is blurred, more like when camera shake is the issue. Except I also eliminated camera shake, as this is an IS lens and anyways I also tried at higher shutter speeds and the problem remains. I also tried it with IS off, same problem.

Lens is fine when subject is say pretty close or far away. It's that midrange that presents a problem. To add a further wrinkle, when I use Live View, the image is fine. It's just when I use the OVF that this problem shows up. Kind of befuddled as to what could be the issue here.

I don't presently have another Canon body to try this on, but I do think the problem is with the lens as other lenses on this body don't exhibit the same issue.

I am probably just going to return the lens for another one, but I do want to make sure I am not missing something obvious or I should try something else.

What AF setting are you using with the optical viewfinder and what shutter speeds?
I have the same lens on my 6D and it is great. It should be sharp wide open and much better at F3.5 or F4. I would expect very good results at F2.8. Try centerpont focus, single shot. Shoot targets at a variety of distances and see what you get. I get good results with 1/60, but higher shutter speeds always help, depending on subject movement. I always use IS unless the lens is on a tripod, but I rarely use it that way.
You may want to try posting a sample or two with more exposure details. Make sure ISO is high enough for good exposures and high shutter speeds. That might help. Try to be sure you are using the shutter correctly. Press down part way until you get AF confirmation, and then squeeze off the rest.

artyH wrote in post #18489113
You may want to try posting a sample or two with more exposure details.

Make sure the full exif information is intact so we can see the detailed settings that are being used.

Some lenses are out of whack and that's that. I encountered an EF 24-70 MkII, brand new which would go from front to back-focus as you changed the focal length and the focusing distance. Returned it to B&H no questions asked and the replacement they sent me was dialed in perfectly.

A prime that has AF problems depending on the distance, is Canon's problem to solve. But if you can return the lens for a replacement, it's not your problem to deal with Canon.

Sent it back if you can.

Return it.

can also be a contrast issue, try something outside with good light.

I agree with the "return it" sentiment. I sold my 35 f/2 IS though I regret it... It worked flawlessly and I tried it out extensively because the 70D I was using at the time was said to have issues at f/2.8 and less.

No need to spend time trying to get a defective lens to work if you are within the return period. One man's opinion.

Phoenixkh wrote in post #18490864
No need to spend time trying to get a defective lens to work if you are within the return period. One man's opinion.

Exactly.

Get a new copy. It's a winner. Total L optics in a cheaper body. I loved mine.

The Dark Knight wrote in post #18488753
Brand new lens picked up just yesterday. Testing on 6Dii body. The image is blurry when subject is about 10-15 feet away at f/2 and f/2.8, improves a bit when lens is closed down beyond that. I've confirmed AF point with DPP software, but lens doesn't appear to be front or back focusing as NOTHING is in focus, the entire image is blurred, more like when camera shake is the issue. Except I also eliminated camera shake, as this is an IS lens and anyways I also tried at higher shutter speeds and the problem remains. I also tried it with IS off, same problem.

Lens is fine when subject is say pretty close or far away. It's that midrange that presents a problem. To add a further wrinkle, when I use Live View, the image is fine. It's just when I use the OVF that this problem shows up. Kind of befuddled as to what could be the issue here.

I don't presently have another Canon body to try this on, but I do think the problem is with the lens as other lenses on this body don't exhibit the same issue.

I am probably just going to return the lens for another one, but I do want to make sure I am not missing something obvious or I should try something else.

Since you said you picked it up, take your camera and the lens with you when you return it. Show the seller the problem and check out the replacement while there.

MFD is about 10', so things should be able to be focused beyond that...

Sorry for digging up an old thread, but I'm having the exact same issue. Camera is 6D and I just bought a used, pristine looking 35mm F/2 IS. After reading about the "ugly bokeh" reviews, I'm surprised how good it actually is. This is truly a lens I want to glue onto my 6D... HOWEVER the focus is only accurate as long as I use liveview, or focus on close distance subject. I thought the center AF point of my 6D was way off, but it turns out the AF point is actually very precise (as I focused on the tip of a Giottos rocket air blower that was right in front of me, and the width of it barely fit into the focus point).

Then I focused on person's face who was 6 feet away from me, center AF point maybe a 1/4th or smaller filling out the face, and the image was constantly out of focus, but you cannot tell if it is front or back focusing, same as OP. I'm not sure what to do. No warranty, private seller, if fixing is expensive I think I'll just sell it.

Steve-22 wrote in post #19438816
No warranty, private seller, if fixing is expensive I think I'll just sell it.

How recently did you buy it and how did you buy it? If you used PayPal they have a buyer protection plan if you get something that doesn't work. Have you tried contacting the person you bought it from?

Scottboarding wrote in post #19438893
How recently did you buy it and how did you buy it? If you used PayPal they have a buyer protection plan if you get something that doesn't work. Have you tried contacting the person you bought it from?

Bought it from private owner in my home country. Pay on delivery in cash (~ 300 euros). Had I chosen ebay I would have had the option to return or get PayPal involved, but also the ones I saw on there went for 400+ so I wanted to save cash.

Anyways, I really want to make this lens work. Just trying to figure out if it is a camera problem or a lens problem (or both)

Steve-22 wrote in post #19439025
Bought it from private owner in my home country. Pay on delivery in cash (~ 300 euros). Had I chosen ebay I would have had the option to return or get PayPal involved, but also the ones I saw on there went for 400+ so I wanted to save cash.

Anyways, I really want to make this lens work. Just trying to figure out if it is a camera problem or a lens problem (or both)

Is it out of focus at all apertures? How out of focus are we taking about? Are the images just a bit soft or are they truly out of focus? If it is accurate in Liveview I doubt it is the lens since it would not know whether yor are in LiveView or not. If it is just a little off perhaps you need to make a micro focus adjustment for this lens in your camera, Remember that Liveview uses the sensor for focusing while the viewfinder uses the separate AF sensor for focusing. A micro focus adjustment may be all you need.

I did some testing at F/2 and F/2.8. I took 3 pictures of a scene: focusing on a a person's face laying on the couch. I used center focus point and have not used focus and recompose technique. Face to camera distance was 5 meters (~ 16 feet). I did this test several times with minimal to no change in distance (took a total of about 20 photos). First two photos through viewfinder, and third one was using live view. Live view was always accurate of course, but one of the two shots through viewfinder was always accurate too. If the first one was blurry, then the second one was well focused. If the first one was in focus, then second one out of focus. When out of focus, it seemed to focus about 1 meter (~ 3 feet) front of subject. Why the inconsistency?