weird lens problem

[colpepper]

My Sigma 75-300 APO AF has a taken on a strange stickiness. The outside plastic of the lens barrel - not the rubber focussing ring or zoom collar - has turned gummy, for want of a better description.
It's kept with other lenses in a dark drawer and none of them have the same problem. If I pick at it with a finger nail the surface comes away like confectionary.

Another Sigma lens has a much less advanced version of the same condition. Has anyone come across this before?

 

[Blake]

Can't say I have. Is it under warranty still?

 

[Musicman]

I've often heard that Sigma's paint finishes are often less durable than you'd hope.

Like this?

http://www.flickr.com/photos/sharpshutter/2217795024/

edit: google provides a bunch of hits http://www.google.co.uk/search?hl=e...ens+paint+peeling&aq=f&aqi=&aql=&oq=&gs_rfai=

 

[colpepper]

Can't say I have. Is it under warranty still?

No, long out of warranty, bought around '94ish. It's as though the rubbery plastic surface has undergone some kind of chemical degredation. It hasn't been in contact with anything weird and the Nikkors with it are fine. If I touch the barrel it leaves a fingerprint and the whole lens outer has the consistency of a half sucked boiled sweet.

 

[colpepper]

This will give you some idea. Note the rubber rings above and below are fine, it's the barrel that's gone soft and sticky.

 

[andrewc]

No solvents or something in the same drawer or nearby ?

 

[lostinfrance]

while on holiday a few years ago my olympud mue 35mm camera was stored in a hotel room with insect repelent tha spilt causing the camera to litery melt,could not ge the battery door open,has it been in any contact with such a item,the stearing wheel is the same on my ford fieta after a day out last year ,the coating looks the same as your lens

 

[colpepper]

No solvents or weird chemically stuff and like I say, the Nikkors and various leatherette camera bits are fine. The parts of the barrel out of the sunlight at the rarely exposed 300mm end of the zoom have degraded exactly the same as the parts in the light.
If I were quessing I'd say some experimental soft-touch barrel coating from the 90s wasn't longevity tested and has gone semi-liquid.

I'll get in touch with Sigma, more in hope than expectation.
edit: a long shot but do you think bubble wrap could have caused it? It hasn't been in contact but there's been some in the same drawer for the last month.