Help -- Black Spot on Lens (not dust)

Need some help from the lens gearheads on whether there is concern with a used lens I just purchased. Lens was graded excellent, the highest rating just below the new and was from one of the top two dealers (will withhold the name until a problem is confirmed). The lens is a Canon 85mm 1.2L, and is very expensive (even as used) as I'm sure everyone is aware. I'm still within the return period if there is a problem, but considering the price of lens I'm more that a bit paranoid about the condition.

My concerns:

1. Focus ring is a bit wobbly, but after some research this appears par for the course for this model. Will disregard and accept this as normal, AF and Manual focus appear acceptable.

2. Black spot on the inside of the front element while looking through lens while off camera. I can see "normal" dust inside the lens, just as with my other lenses and this spot is different, slightly larger than a piece of dust and not translucent around the edges like dust, its pure black and more round. Tried panning over different colored surfaces and discovered that the black spot would turn white when panned over a pure black background. Other normal imperfections in the glass such as bubbles also appear white over the black surface, but those disappear when the lens is panned away from black background. Just my suspicion but think it may be a tiny chip in the glass that is diffracting the light - it acts just like a chips in a car windshield that turns black when viewed from an angle.

Its 1:30AM, will perform some serious test shots in the morning to see if its visible in any photos. Just wanted to throw this out to those with much more expertise than me to see if there should be cause for concern.

Appreciate any and all helpful replies.

Took several dozen blue sky shots at f/16.... Examined in LR, everything is clear except for three dark spots in the middle of the frame. They look like sensor dust, so removed the 85MM and replaced with the 70-200mm, took a dozen more at f/16 .....

Sur enough spots are in the exact same locations...

Guess I will forget about the black spot on the lens, doesn't seem to effect anything.....

I just had CMS done for the Camera body and 70-200mm lens. I just took them out of the box for the test.. Is it normal to pick up sensor dust that quickly, or should I complain to Canon?

I'm going to try the internal camera shake mechanism and take some more shots.

Get a rocket blower.

Ya, I got one.. Just wondering why I have to clean spots after it just returned from CMS.

Canon services is getting quite the reputation. I sent my 70D in for the same thing twice. Both times I was told it was repaired. It was the same as when I sent it in, both times. Check out the 7DII focus issues thread if you want to see 'service' done wrong.

Bassat wrote in post #17824988
Canon services is getting quite the reputation. I sent my 70D in for the same thing twice. Both times I was told it was repaired. It was the same as when I sent it in, both times. Check out the 7DII focus issues thread if you want to see 'service' done wrong.

Thanks Tom .. ill check out that thread... It doesn't look like they even touched the Camera, in addition to the sensor spots I found a piece of hair in the viewfinder and none of my custom settings were erased as expected. I shelled out $100 for Gold CPS status, but this year will be the last.

I have enough points (Canon equipment) to qualify for some level of CPS. I am not sure I understand the logic of paying Canon to provide 'free' services. After reading about Canon services lately, I just plan on taking my stuff to a local camera shop for repairs. My brother has never had these issues. He shoots Nikon. Nah, probably just a coincidence.

Bassat wrote in post #17825014
I have enough points (Canon equipment) to qualify for some level of CPS. I am not sure I understand the logic of paying Canon to provide 'free' services. After reading about Canon services lately, I just plan on taking my stuff to a local camera shop for repairs. My brother has never had these issues. He shoots Nikon. Nah, probably just a coincidence.

Not to stray too far off topic, but the grass isn't any greener on the Nikon service repair side. I sent them a lens twice for the same problem. First time back it was not only not repaired; it came back dusty on the inside and with parts loose. The second time around they got it right. I was upset with all the time wasted.

I just went through the gear list for CPS. I have 67 points, and qualify for Gold level CPS services, which costs $300/year. I have been shooting Canon since 2009, so let me assume 8 years (including 2016) of membership. That would have cost me $2,400. For this (to me) large pile of cash, Canon offers:

Some useless trinkets: lens caps, strap, 'gift'
Discounts on more stuff I don't need.
Maintenance service. (Sorry, my philosophy is: If it ain't broke, don't fix it.)
30% discount on repairs. (Have never needed a repair.)
Free shipping. Both ways.

To summarize: For my $300/year, I get nothing of value.
Example: My most expensive single item is the 100-400L. Assume I drop it and Canon can repair it for $1,000. The 30% discount saves me $300. Oh, boy. It would be cheaper for me to NOT be a CPS member, and buy a refurbished 100-400L II direct from Canon.

CPS membership and my part of repair: $2,400 + $700 = $3,100.
or
Refurbished 100-400L II: $1,500.

Holy crap! I could buy two of them, and still not spend the money I'd have wasted on CPS. I just do not understand the thought process behind PAYING Canon to provide FREE services. As Mr. Spock would say, "Illogical."

Bassat wrote in post #17841884
Holy crap! I could buy two of them, and still not spend the money I'd have wasted on CPS. I just do not understand the thought process behind PAYING Canon to provide FREE services. As Mr. Spock would say, "Illogical."

Agreed ... The only reason I purchased the Gold Membership was for the CMS cleaning services. After the sensor came back dirty I called and cancelled the membership, for $100 I can clean the sensor myself (and apparently do a better job).

DanangMonkey wrote in post #17841887
Agreed ... The only reason I purchased the Gold Membership was for the CMS cleaning services. After the sensor came back dirty I called and cancelled the membership, for $100 I can clean the sensor myself (and apparently do a better job).

I would be afraid to clean a sensor myself. Over 50,000 shots on 7 different bodies in 8 years, and I've never needed to clean a sensor. A local shop charges $35 for sensor cleaning.

If you never clean the sensor yourself, what do you do if you are out in the field on a 2 week vacation and your sensor gets dusty?

With the tools available now, it just doesn't make sense to me why anyone shooting landscapes (not quite sure why else you would shoot at f11+) would not clean their own sensors.

I can see sending it in for wet cleaning or something if you often work in dirt environments, but not being willing to dab it with a gel stick, I personally don't get.

ejenner wrote in post #17843605
If you never clean the sensor yourself, what do you do if you are out in the field on a 2 week vacation and your sensor gets dusty?

A puff from the rocket should fix it. Has happened only once or twice to me in more than 9 years. In an unsolvable sensor crisis while away, I guess you could resort to buying a used Rebel body for $500.

Macro.

I have heard some bad stories about cleaning a sensor with liquids. Still, it is probably a good idea to buy one of these kits and take it along just in case.

Lets PLEASE end this thread..

This thread was NOT originally about Sensor cleaning, and it has drifted well beyond the intended topic.

i'm going to start using an independent repair service once a lens is no longer under warranty. should be a little cheaper and maybe they will actually tell me what they do to the lens and possibly not charge me if they do nothing.