Damage caused by hot grinder sparks. This is a close up of damage to the coating of a cheap Sigma zoom (28-70mm) lens. The damage was caused by hot sparks from a hand-held grinder as it was grinding some steel. I had been going for some long exposure low light shots of the work being done. Unfortunately, I had gotten too close to the action. You can see in the image where hot bits of steel (or maybe it's carbon) have stuck to the lens. I haven't tried to use this lens since then, and in fact haven't even processed the film that I had shot that day (several years ago), so I don't know if this damage has degraded the (already poor) performance of the lens. Let this serve as a lesson though. If you have a lens that you value, don't try this at home! :-)

whatever you do, KEEP THAT LENS! Damaged equipment that still works can be the perfect touch to creating a certain atmosphere you may want later down the road. Don't throw it out. On yer next roll, take 4 or 5 shots with it, and shoot the rest normally. See what the results are. they may look REALLY bad, but hey, Antoonio's work always looks scratched up and dirty (well, not always, but some of it is), and are they not the shiznick, or what... hell, you may even wanna scratch it up summore!

Ok Slynky, here's a test shot using that Sigma lens. I don't think the performance has been degraded much at all...

Nope, hardly noticable.

Yikes.....all I keep thinking is that you were lucky that stuff didn't fly in your face or eyes.

I never said the performance wouldnt suffer Salina, I said the strange results you would get from it from then on might be useful. True, in that shot, what the lens did was mess with it to no end, not in a good way really, but are you telling me that looking at that strangely displaced colour, you couldnt find any application for it?

Ah Slynky, I was pulling your leg, man! I wasn't being
pissy; I was making a joke about the quality of Sigma
zoom lenses in general ("performance hasn't degraded"
from new). That self-portrait was a mock-up done with a
cotton ball stretched over the lens of my digital camera.
The color effects were done in the Gimp: decompose image
into CYM components, motion blur each component at a
different angle, then recompose the image.

Heh! Sorry if you misunderstood. I figured you'd be tipped
off by the speed with which I replied (2 hours).

LOL. I agree with Slynk And Michelle. Those little dings shouldn't cause as much problems as you are seeing in #3, but may be very interesting when shooting into the light. And WEAR SAFETY GLASSES. You'll really regret it if you don't! Do you have problems in general with Sigma lenses? I love my Sigma 180mm macro for the canon eos. I hate my Sigma 170-500mm zoom. The 180mm macro is my general purpose lens, and is the best I've ever had (that I could afford). The long zoom is crap.

Ditto on all of what Alpha says. And Misha, to answer your question, after reading all of the bad reports on Sigma zoom lenses, I feel very fortunate to have had my Sigma zoom on the camera rather than the plain-jane Pentax-A SMC 50mm f2 prime that came with the K1000. It seems from the reports that Sigma zoom lenses, especially when used with the aperture wide open, are optically pretty poor. From what I've read, the Sigma primes aren't as bad, which would explain why your 180 macro seems to perform well as opposed to your Sigma zoom. I've never found any explaination as to why the zoom lenses suffer and the primes don't. It would seem that poor optical perfomance would have to do with lens element quality, which should be the same for zooms and primes from the same manufacturer.

Actually I liked your self protrait effect. It reminds me of 3D images. Yup Yes it does! Quite nice. Bsteph