Probably my favorite longish lens for many years was a Pentax A 70-210. Had it been an F, I. might still have it. J
Sent from my iPhone > On Oct 29, 2016, at 2:36 PM, Ken Waller <[email protected]> wrote: > > I've had and heavily use a brand new F 70- 210 for 28 years and have only one > real issue with it - the focus barrel, to which filters screw into, rotates > when it tries to attain focus, and subsequently I have to remember to reset > the polarizer filter - it obviously not a biggie, which is to say I really, > really like that lens, to the point that a few years back I picked up a > duplicate even though The original lens continues on like a storm trooper! > > Probably my third most used lens. > > Let's just keep it a secret P.J. > > > -----Original Message----- >> From: "P.J. Alling" <[email protected]> >> Subject: Really mini review comparing the F 70-210 to Sigma Zoom 70-210. >> >> Most people don't care. However I recently acquired, a "new", at least >> to me F 70-210 from KEH.com. So I thought I'd post the salient points >> of the pros and cons of the two lenses. >> >> First off I think I'll say I don't hate the Sigma, I just don't love it >> either and life is too short to put up with things you don't love if no >> one is paying you for too. >> >> Physical comparison, the Pentax is about 1/2 inch, (~12mm), longer, only >> slightly wider in diameter, and surprisingly not that much heavier than >> the Sigma. >> >> The Pentax is mostly metal, and the Sigma is mostly plastic, most of the >> weight in both lenses seems to be the glass. >> >> I've partially torn down a F 70-210 Pentax, (and also received back the >> remnants of another used as a parts donor), so while looking at it from >> the outside it appears to be a much more solid build, there are >> decisions on interior construction that aren't quite so confidence >> inspiring. I haven't torn down the Sigma but if it's anything like the >> plastic Pentax lenses I've had apart, it is, other than in materials, >> maybe better built. It would certainly be harder for things to get out >> of alignment, (but once they do, in most cases, you might as well throw >> the whole mess away). >> >> The Pentax has a very long focus throw, the focus ring is very narrow, >> manual focus dampening is relatively light, but not too unpleasant, and >> can be very accurate due to the long focus throw. Auto-focus can be slow >> if the camera decides to rack the lens from infinity to closest focus. >> The Sigma has a much wider manual focus ring, slightly better dampening >> and a much shorter focus throw, about 45° as opposed to almost 130° for >> the Pentax, so focusing when the Camera decides to rack the lens from >> closest focus to infinity is a bit faster. Manual focusing is still >> pretty easy to be fairly accurate and one of the things I really like >> about the Sigma is, it's, for an auto-focus lens, luxurious wide focus >> ring. That said, the K-5II very seldom racked the whole focus length to >> find proper focus, except under the dimmest of lighting conditions. >> >> Optically the Pentax is just better, maybe not much, but enough that it >> was noticeable. Pretty much at all focal lengths and apertures that I >> normally use. I've owned three F 70-210mm lenses and the first was the >> best, sharp at all focal lengths, the second was a little soft at around >> 210mm but still not too bad, the new one is probably somewhere between >> the the first and second. The Sigma was never quite as sharp at any >> focal length as the second Pentax. Not really bad it could be mostly >> corrected in post processing, just not as quite as sharp. >> >> The Pentax focuses closer, the Sigma claims a 1:4.7 reproduction ratio, >> (it's written right there on the focusing scale), the Pentax according >> to Boz' site has a 1:4 reproduction ratio, it doesn't seem like much of >> a difference, but once again it feels noticeable, I was always >> frustrated with the Sigma in that regard. >> >> The Sigma is not as flare resistant as the Pentax, or maybe it is in >> different ways. It seems to be more prone to veiling flare, so if a >> bright light source is even close to being in frame there is a >> noticeable loss of contrast and sharpness, the SMC coating on the Pentax >> even though 15 years older is much more effective than the Sigma's. >> Still it's hard to get actual flair artifacts with either lens at least >> on a digital camera. I don't have the dedicated lens hood for the >> Sigma, and an after market lens hood was one of those things I kept >> putting off buying. I adopted an old Super Takumar lens hood for the >> Pentax which works perfectly for the focal lengths on APS-C. >> >> Bokeh is different, but a lot of that has to do with how busy the >> background is neither of these lenses will ever be mistaken for being >> fast, so that's kind of a non issue. There are lots of other minor >> differences, most of which aren't important in the digital era, such as >> color rendering more a matter of taste, and easily manipulated in photo >> software. >> >> I guess I could go on a lot longer. Let's get to the bottom line. >> >> The Sigma is a real bargain, you can pick one up for less than $40. in >> Ex to LN condition, (or as KEH.com would call it Bargain), or for free, >> the way I did. Optical and mechanical quality is reasonable, you get a >> lot more than your 40 bucks worth. It's so cheap that it's almost not >> worth selling it. So I'm not going to. It will sit on the shelf >> collecting dust, (as a backup for that inevitable day when something >> comes loose in the F 70-210 and I have do decide to repair or replace), >> next to my film cameras and actual great lenses I seldom seem to use >> because they are inconvenient, (more convenient to use on a Pentax >> Digital than if I was a Canon user with a collection of the same >> vintage, but still)... >> >> The Pentax is just better, slightly heavier, slightly bigger, mostly >> metal with that cool feel of solidity that the K-5II has in the hand. >> They don't look like they were made for each other, (in fact F lenses in >> that greenish grey color are some of the silliest looking lenses in my >> opinion), but they feel like they were made for each other. Sharper at >> all focal lengths and f stops, than the Sigma, more flair resistant, >> just all around, better, and you can find it /nearly/ as inexpensively >> as the Sigma. >> >> -- >> I don't want to achieve immortality through my work; I want to achieve >> immortality through not dying. >> -- Woody Allen > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
