[Frogfish]

I love this lens but don't use it that often any more - I'm more of a prime guy.

It is very very sharp and amazing value of money. I've not had any particular problem with focusing or keeper rate. In fact in shooting paid events this is an excellent lens I use a lot with a very high keeper rate when used with the Metz 50.

In all cases of focusing accuracy you also have to factor in User-Error. I'm not suggesting that is the issue here (though I think it most definitely is if the OP was shooting at f32) but there are many factors that may influence a shot and we as the operators sometimes forget one or more and then blame the camera/lens.

[emalvick]

Interesting comments and, Frogfish, I think your suggestion is a good one...

I recently thought I was having issues with the lens and started looking at making adjustments (I had mostly been successful with it with no fine lens adjustment). In attempting to make evaluations to determine whether I had a back focus or front focus issue, I think I started over-analyzing and let my emotions (anger) at the lens get the best of me... Then at some point, I stepped back, took the lens out for a walk and took some typical photos to find that the lens was just fine...

The original perceived focus issues I could never fully figure out other than I may have had a bad day out shooting and made a perceived soft focus worse than it really was by pixel peeping too much. Then I tried to correct focus by taking minimum focus distance type shots at odd perspectives of odd items in odd lighting that clouded my judgment.

All in all a little user error and emotion clouded my evaluation of the lens at the time. I also think I found that the worst shots I had on the original day that made me think there was something wrong with the lens were actually from another lens that I had just purchased and I hadn't developed a feel for. I find it amazing how using a new lens is similar to driving a new car. You can get decent results, but only with a bit of experience do you really get a feel for it. Same goes for the camera, too.

[123jippo]

In another thread I did ask 'what is ur best landscape lens?' Most common asnwer was Da16-50. I wonder if Tamron 17-50 is also so very good for landscapes especially when using smaller apertures like f11-f16? I also wonder why nobody said Tamron 17-50 there...

[subidoc]

In another thread I did ask 'what is ur best landscape lens?' Most common asnwer was Da16-50. I wonder if Tamron 17-50 is also so very good for landscapes especially when using smaller apertures like f11-f16? I also wonder why nobody said Tamron 17-50 there...

That being said, how is the 16-45/4 compare to the pentax or the Tamron? Any failures with these lenses? I am looking for some coverage of wider angles with an AF lens (as all other lenses are MF primes)....

[cali92rs]

I also wonder why nobody said Tamron 17-50 there...

I did...

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/195064-your-be...pe-lens-2.html

And I remember others mentioning it as well.
It is a great landscape lens.

[123jippo]

I did...

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/195064-your-be...pe-lens-2.html

And I remember others mentioning it as well.
It is a great landscape lens.

Yes u did...hhmmm I must admit that I did not noticed answers with under 1K postings, did try to look only Pentaxveterans opinions

Thank u thats all i wanted to make sure, I will get my Tamron 17-50 as soon as possible

[tlwyse]

I picked up a Tamron 17-50 a few months ago in a barter deal for my Pentax LX and PZ-1p....great lens.

Not sure why the Pentax DA* 16-50 keeps coming up as an "excellent" lens....I tested one against the newer Sigma HSM 24-75 some months ago and I thought it was a piece of junk.....at least in terms of sharpness it was inferior to either the Sigma or the Tamron. Maybe it has great build quality....but in terms of image quality, I was not impressed.

Oh, and best landscape lens? Easy...Pentax DA 12-24mm f/4.....that lens has been in my bag forever but it continues to amaze me every time I use it. If that thing had a little more reach, say 35-40mm, I doubt it would be off my camera for very long....but the Tamron 17-50 is easily the most versatile lens I have right now.

[tlwyse]

Forgot to mention...

Yesterday I came across a scene that I thought would be a nice scene to have nice and sharp from the front of the frame right to the back of the scene, so I closed the lens all the way down. I used timer, tripod, everything so I would get the results that I hoped for. Was I ever disappointed when I got home. I did a few frames, just in case, but each one is soft as hell. No good detail anywhere in the image. Does this lens really go to hell closed up all the way?

With digital and the APS-C sensor size, any lens will turn to shit when stopped down all the way....lens resolution is diffraction-limited at that point.

Me, I never stop down less than f/8 if I can help it...in all my testing, sharpness starts to noticeably degrade around f/11 and below.

On the front/back focus thing, I was frustrated as well with the Tamron when I first got it....until I spent about half a day with my LensAlign and doing careful focusing tests @ 17, 35 and 50mm and using apertures f/2.8 and f/5.6 and at both 20x and 50x focus distances. I found that it was actually pretty consistent at all those focal lengths (worst nightmare..different AF adjustments for different focal lengths!) and distances. At least on *my* K20D body, the AF adjust had to be almost maxed out at +8 to +9.....in fact, as I do more focus tests, I'm finding that virtually all my lenses, even some old manual focus Pentax-M lenses, take a +6 to +8 adjustment.....my theory/experience now is that the AF back/front focus adjust is more a function of the camera body as opposed to individual lenses.

Terry

[jzackery]

I am strongly considering purchasing this lens from eBay but seeing as there's some good and bad copies would it be recommended Not to buy a lens from a Japanese or eBay vendor? Would buying a US model be advised or does it matter,you get what you get kinda thing? I'm curious because the ones sold in the US are selling for around 150 more on eBay than those from Asia and I can't say I wanna deal with an international return but don't want to spend hundred dollars more as I'm on a college budget haha

[VoiceOfReason]

I have the lens and to tell the truth it's on my K5 more than anything else.

[msatlas]

I am strongly considering purchasing this lens from eBay but seeing as there's some good and bad copies would it be recommended Not to buy a lens from a Japanese or eBay vendor? Would buying a US model be advised or does it matter,you get what you get kinda thing? I'm curious because the ones sold in the US are selling for around 150 more on eBay than those from Asia and I can't say I wanna deal with an international return but don't want to spend hundred dollars more as I'm on a college budget haha

KEH has a used one for $349.

Pentax Digital 17-50 F2.8 TAMRON ASPHERICAL DI II SP INTERNAL FOCUS LD XR (A16) (67)(APS-C) WITH HO DIGITAL SLR ZOOM SUPER WIDE ANGLE LENS - KEH.com

They have a decent enough return policy that you should have enough time to check for focus issues & send it back if needed.

If you have a body with AF fine adjustment you should most likely be able to dial it in.

[Jonathan Mac]

I have a love / hate relationship with this lens. Just curious as to others thoughts on this lens. Here's my story with it.

This lens, when it focuses accurately seems very sharp. (for the most part, see my other comment below)
I do find that my keeper rate with this lens is lower than most of my other lenses, as it seems to miss focus more times that I'd like. I've tried to check for Front / back focusing issues, but always seem to get mixed results.
Yesterday I came across a scene that I thought would be a nice scene to have nice and sharp from the front of the frame right to the back of the scene, so I closed the lens all the way down. I used timer, tripod, everything so I would get the results that I hoped for. Was I ever disappointed when I got home. I did a few frames, just in case, but each one is soft as hell. No good detail anywhere in the image. Does this lens really go to hell closed up all the way? I've owned this lens from new, so I could send it in, but if it's just nature of the beast for it to be this way, then so be it.

I have had exactly the same experience. I suspect that a lot of the FF/BF issues reported with this lens are actually down to it's "loose" focusing. By this I mean that it's correctly calibrated to the body, but just doesn't have consistent focusing. There's absolutely nothing you can do to prevent it, but I would recommend checking focus after every shot. I have my K200D set up to zoom to 8x with just one click of the dial, so with that one click I know if the shot's in focus. Closing the aperture to the minimum will bring you into refreaction-limited territory and is not recommendable. I never stop down past f/16 maximum.

I have had some shots which were soft from the background to the foreground despite using a mid-range aperture and no reason to expect misfocusing.

Auto-exposure is similarly hit-and-miss, and results should be checked after each shot.

In the end, it's a good lens but you need to learn how to work around it's failings. For me, the Sigma equivalent is too expensive and the Pentax too, with the addition of SDM failure and de-centering risks. The Tamron is the best of a bad bunch when it come to fast standard zooms for Pentax, you need to learn your way around it.

I find this lens invaluable for the flexibility needed when traveling, but in day-to-day photography I prefer the reliability, IQ and pleasure of primes.

I would STRONGLY recommend trying before buying, and that means going to a shop for it, not online.

[c a sugg]

I love the overall quality of mine. However about week ago I had the zoom control ring go askew in the middle of a shoot. Seems to go through it's range OK, but at 17mm it's only at the 35mm mark. Plus there's considerable play before it engages. Right now I'm keeping it parked at 17mm. It's been regular use for 2 1/2 years.
Has anyone else experienced this?

[mlatour]

I've had that zoom ring problem too,
first the markings were not in line with the actual lens setting,
after a while the zoom ring became 'disconnected' from the internal mechanism and required warranty repair.

I finally got rid of this lens because of annoying front/back focus issues. Using the 'debug mode' trick
in my K-x I could tune only one end of the focal range, to be 'perfect' at 17mm it was than then front focus at 50mm.

Sold it and kept using my Sigma 18-50mm f2.8 EX DC Macro,
better build quality lens and just as sharp as the Tamron when stopped down to f3.5-4

[sb in ak]

I love the overall quality of mine. However about week ago I had the zoom control ring go askew in the middle of a shoot. Seems to go through it's range OK, but at 17mm it's only at the 35mm mark. Plus there's considerable play before it engages. Right now I'm keeping it parked at 17mm. It's been regular use for 2 1/2 years.
Has anyone else experienced this?

Are you the original owner? If so, I'd try to get it fixed as I think there is a 5-year warranty. (I don't believe the warranty is transferable though).