Contamination in lens

It looks like haze- and the circular wipe marks look like someone might have tried to clean it before.

What is the history of this lens/ How long have you had it?
 
I think Brian is right.
The light feeling when focusing shouldn‘t be because of dried lubricants, the opposite would be the case. Maybe the helicoid is worn and needs special grease to give a more tight focusing experience?
 
This is an expensive lens. I would send it to a professional to have cleaned. They can also evaluate the circular wipe marks.

Or- just use it. Most lenses will show some haze with a "Flashlight" test. If you get flare when using- have it cleaned. If happy with the results, and do not want the expense of having cleaned- just keep using it.
 
bjolester said:
I have a very nice Pentax tele lens that has some kind of contamination on the inner lens element on the moving lens group. The affected glass is close to the aperture blades. The focusing ring on the lens feels unnaturally light, as if lubricants have somehow dried up. Otherwise the lens fuctions as it should, the contamination is only visible when shining a LED light through it.

Do you believe this contamination could be haze? It does not look like fungus to me, but then I do not have much experience with lens contamination. What do you think? ...
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As has already been pointed out, it's haze with cleaning marks, but I've seen much worse. If you decide to send it to a professional for the focusing tension issue, I'd have the haze addressed at the same time; otherwise I'd probably use it the way it is without worrying about it (and I'm pretty anal about these things).
 
santino said:
I think Brian is right.
The light feeling when focusing shouldn‘t be because of dried lubricants, the opposite would be the case. Maybe the helicoid is worn and needs special grease to give a more tight focusing experience?
Click to expand...

That really depends on the nature of the lubricants used. Ones with a higher oil to solids ratio and ones which are more lightly applied do tend to feel lighter as they dry out. The classic example is the older Nikkor F mount lenses, which as they get older tend to lose all their focus damping and become very loosey-goosey as the lubricants dry.
 
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