EF 24-105mm f/4L Soft and Hazy

[wilmark]

I have the above lens that is very soft and hazy - but i cannot see any dust or mold. I think i want to try to tear it down and see if i can do anything with it.  Like this guy is doing here: 

https://www.youtube.com/watch?v=bdShwMk-LDc

But he says that the "Axis Test" showed poor results early in the video. I gather that some of the elements are misaligned causing the blurriness. I'd like to confirm that it is indeed an axis problem. Any idea what exactly is an axis test? What charts are used? Is it the same as a lens calibration test?

[Anonymous]

Not exactly a direct answer to your question, but do you get good focus when using live view shooting on the camera? Live view uses a different focus system than viewfinder shooting. If it is focused in live view, then the lens is not at fault.

[Waddizzle]

Do not take the lens apart.  You can disassemble it with two hands, but you’re gonna need about eight hands to put it back together.

What camera are you using that produces hazy results?  Do you get hazy images with only this one lens?

[kvbarkley]

I am going to guess that it is the "newspaper test" as shown on the third page of this page:

https://bobatkins.com/photography/technical/testing_lenses.html

[wilmark]

I have about 5 other lenses including the 70-200 which focuses really good - either live view or normal shooting. The camera can do with some cleaning - its a 5D Mk 3 thats was bought in 2013 i think when it just came out and have never been serviced. But the 24-105 had been my main lens until i sent it to canon to repair and it came back with this problem. See the photo below - not a good photo but it gives shows the problem - the haze tends to be bad as you move away from the center and the focus appears to be somewhat off. And this is an outdoor photo. 

[wilmark]

Thanks for the advice, I will need to watch more videos and make sure i can document the process. and know how to get it back. But its a skill i'd like to be able to do as i find that Labor cost on servicing is a real killer. 

See my post above to 5 DIV for the description and the lens/camera issue.

[Anonymous]

I would send it back to Canon and tell them of your issue after they repaired it. I would think that they would warranty the repair. Don't mess with it yourself.

[wilmark]

I think i need to give some backstory. A few years ago i sent my EF 24-105mm f/4L to Canon USA (from Trinidad & Tobago), for canon service because it had an Error when i tried to use it. Canon Charged me 350 in Labor (no parts) and repaired the lens and shipped it back. Because this was outside of the US, I had the camera returned to a family member in Florida where i visit twice per year. When i got the lens back i realized it was not focusing properly - 80% of the time it would refuse to focus, Eventually over time, the focusing improved to where today it focuses fine, but the lens takes horribly soft pictures - hazy especially outwardly. I could see no signs of dust or mold inside the lens. Canon told me because of the delay they wont fix it unless i pay for new service. (about 2 months after they sent it back)

[Anonymous]

I still think that you don't want to take it apart yourself.

Are you using a filter or lens hood on the lens?

[wilmark]

Yes i have a Hoya polarizing filter that remains on - and the hood never comes off.