Help Needed!!! Wonder if it's fungus problem...

[evilorgi]

Hi all,

I have a 24-105L and a 50f1.8 that is plagued with this 'dust' problem when i inspect their rear element while cleaning my equipment. The 'dust' is more like a spot, that spreads over an area probably the size of a 3.5mm audio jack diameter.

For the 50f1.8, the 'dust' is not at the external of the rear element but the spot seems to be rather big. I see this exact same 'dust' on the external of rear element of my 24-105L. Hence i used a lenspen to clean out the spot thinking that it's just smudges or something like that.

Upon cleaning, the spot smudges and spread over a slightly larger area. The stain wasnt completely removed despite cleaning thoroughly with the lenspen. Although the spot itself was removed, there is a stain over the place where the 'dust' once was.

What can i do now? Is this a fungus problem? Please advise!

 

[tecnica]

you clean too aggressively until the coating come off huh?

post a pic, easier to understand your situation.

 

[evilorgi]

erm.. the mark on the 24-105 is not visible under norm condition now! however under condensation (air frm breath) you will still see the mark there.

 

[evilorgi]

any idea how much cleaning of the lens would cost? i am thinking of sending it to csc or 3rd party workshops? there is a cs-er here by nickname of fatigue that provide such services too? any idea how much would it be??

 

[BraveHart]

Both lens are still current products under Canon's lineup. Just send it down to CSC lah.

 

[evilorgi]

Both lens are still current products under Canon's lineup. Just send it down to CSC lah.

but both without warranty liao, do you think it's cheaper to send it to 3rd party for cleaning??

 

[DigitalCamera]

but both without warranty liao, do you think it's cheaper to send it to 3rd party for cleaning??

Can try Camera Hospital, but not all the time 3rd party shops are cheaper, sometimes CSC might be cheaper.

 

[spartacus.ret]

the mark on the 24-105 is not visible under norm condition now! however under condensation (air frm breath) you will still see the mark there.

if you can't see the "mark" under normal conditions, it is unlikely to be fungus.