Originally posted by dcshooter No, it would not take anywhere near that long , and to suggest so is quite frankly laughable. There is zero evidence of separation from that photo, and that is the only thing that would make it take anywhere near that long, and that is if you use Canada balsam as your cement rather than UV cured synthetic.
If the lens elements are not etched (and it could be the case, since Pentax coatings tend to be much more resistant to etching than most others), it would take 1-2 hours tops in the hands of an experienced lens technician to do a full CLA with fungus removal on a simply constructed lens like this. . Estimated time if I were doing it: 10 minutes for disassembly, 15 minutes for cleaning the elements, 15 minutes for a good scrub and relube of the helical (the fungus can and does feed on the helical grease), 15 minutes for a good alcohol/acetone dip of the internal mechanics to clean and kill fungus and a scrub of the barrel components with hot soap and water, followed by 15-30 minutes for reassembly. Once cleaned, there would be no perceptible difference in optical performance.
To put it in perspective, I was able to do a CLA and anodizing strip, re-anodize and hand-coloring on this very model of lens for a PF member in just under 3 hours.
Now if the elements are etched, there is no amount of re-cementing that will do anything to help it. The spots I am worried about are the little "dots" in the middle of the webbed patterns, as that is where it is most likely to have been etched, but I've successfully cleaned SMC coated lenses that appeared just as bad as this.
For $240, it might be worth the gamble, since the exterior looks to be in great shape - If it's optically irreparable, you could probably part it out and make most if not all of your money back, but it might take a while. And that's not considering the value of the 28mm. If it cleans up successfully, you are looking at doubling the value. At $50 less, it would be a no-brainer. And remember, even with etching, once the webbing was cleared out, the performance hit would likely be nearly imperceptible, so if you are not planning on re-selling, this could be a very affordable way to get to 1.2.
My advice is to contact the seller and see if he'd accept an offer of $150-$175. And go for it.
Originally posted by dcshooter My advice is to contact the seller and see if he'd accept an offer of $150-$175. And go for it.
Yeah, the original asking price is a little too high with this bad a case of fungus. The waste products of aerobic (oxygen breathing) aren't usually too bad about etching. However, Anaerobic fungus has nastier waste products. When a lens has this developed of a case, there is a higher chance (if the lens is well sealed) that the aerobic fungus consumed all the O2, leaving a good environment for the nasty stuff to grow. Given the lens model and severity, this one looks risky.