On Wed, 3 Oct 2018 12:49:24 -0400 "P. J. Alling" <webstertwenty...@gmail.com> wrote:
> <https://web.archive.org/web/20110317023023/http://members.shaw.ca/hargravep/70-210.htm> that was instructive. i don't think i'll have the stomach for it... > I wouldn't say I've had bad luck with the lens, anyone who's seen my > equipment knows I don't baby it, (though in the case of the 70-210mm > my current version looks very nice, I've been a lot more careful with > it), the biggest problem is a lot of parts are now made of > unobtainum, and while the outside of the lens is very robust metal or > plastic covered metal in many cases, (though there are a lot of > purely plastic parts), simple vibration over time, will cause some of > the interior screws to work loose and get into places where they can > wreak further havoc beyond the original issue of the screw coming > loose. > > The information brush is especially fragile, and is easily damaged by > at least two different basic failures, mostly because the first > inkling that there's something wrong with the lens is the zoom ring > going beyond it's limits, which mangles the brush. > > Once that's happened you'll have to fabricate your own brush as no > repairman I know of will do it for you, they don't have the tools and > won't improvise beyond a certain point, for fear of being blamed for > further problems later, and well the lens just not having that high a > resale value to make it worth trying to replicate such a delicate > part. > > In case you're curious, part of my information comes from partially > disassembling one of my lenses on my own*, part comes from the > information I got through email conversation with the tech who fixed > my second lens, and part from this page > > <https://web.archive.org/web/20110317023023/http://members.shaw.ca/hargravep/70-210.htm> > > by a former member of this group, unfortunately now deceased, stored > in the wayback machine. > > *This not to blow my own horn by the way, I got to a point where I > found the mangled brush and realized that I'd get no further without > jigs and tools I just didn't have and were beyond my poor skills to > synthesize. A shame really as the first lens was the best optically > of the three, second being the worst, but not my much and the current > one being somewhere between the other two, (ah, sample variation > strikes again). > > On 10/2/2018 9:00 PM, Subash Jeyan wrote: > > i sure hope i have better luck with the lens than you've had. it > > didn't cost much so, fingers crossed, i think it's a bargain on the > > whole... > > > > > > On Tue, 2 Oct 2018 15:20:38 -0400 > > "P. J. Alling" <webstertwenty...@gmail.com> wrote: > > > >> I've owned three of them, the biggest problem is they are getting > >> old, first sold with the SF series bodies, (1984ish), first > >> "successful" Pentax auto focus system. > >> > >> There are a number of points of failure that become more likely as > >> the lens ages. \ > >> > >> The problem is that the replacement parts are all from donor lenses > >> which have the same wear. > >> > >> Don't get me wrong I love the lens, but of the three I own, one is > >> in pieces for parts to repair the second which is now jammed, > >> which I didn't try to get repaired because I was able to buy the > >> third, for less than the cost of the repair and shipping. > >> > >> > >> On 10/2/2018 10:42 AM, Subash Jeyan wrote: > >>> i've just got myself an F 70-210 f4-5.6, though it'd actually be > >>> two weeks before i get my hands on it. the reviews of the lens on > >>> the PF were pretty good and i was curious about the images taken > >>> with the lens. so i went to PPG to have a look. most of the > >>> images for that lens in PPG seems to have been taken by Ken > >>> Waller. indeed, the first 15 images or so were his. superb stuff. > >>> recognised a few other names from the list too. > >>> > >>> i am glad i bought this lens though it doesn't necessary follow > >>> that the images i make will be half as good. i was planning to > >>> take the DA 55-300 on my trek in the himalayas next month but > >>> wondering if i should take this lens instead (coupled with the > >>> sigma 17-50/2.8). > >>> > >>> here is the PPG link for this lens if anyone else is interested: > >>> > >>> https://pentaxphotogallery.com/photos/gallery/query?camera=&lens=930 > -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
