[SMeK]

Hey,

I was very happy with 16-45 and my K-x. I also have 50-200, 35 2.4 a bunch of manual primes (Pentax M 50 1.7, cosina 100mm - great lenses) K-x and 35 2.4 did not go well with each other (Focusing issues) and that was my forgotten gem in drawer.

And now i bought K-5 iis. 35 2.4 works perfect and IQ is crazy good. But i am not happy with my wide part. I need something wide which is close to 35 2.4 in terms of sharpness. On photozone.de I considered a 15mm ltd but it seems that 16-45 is shaper on wide end according to charts. Weird. Prime is not must have, but i want lens wich is sharper then 16-45 and with great AF. Any ideas ? Maybe sigma 17-70? 10-20? Tamron 17-50 (i heard about focusing issues with this lens?) Or ? Thank you

[northcoastgreg]

Assuming you have a good copy the DA 16-45, you won't be able to find many K-Mount lenses that are significantly sharper at the wide end (although there are lenses that are a little sharper). What does exist are lenses that, because they are inherently contrastier, produce images that look sharper, even at smaller sizes (the advantage of resolution only kicks in with large crops and/or big prints). They would include the DA 15, the DA 21, the DA 12-24, the DA* 16-50, the DA 17-70, and probably the Tamron and Sigma f2.8 standard zooms as well.

[TER-OR]

The DA21 is quite sharp and in the middle of this range.

[normhead]

Hey,

I was very happy with 16-45 and my K-x. I also have 50-200, 35 2.4 a bunch of manual primes (Pentax M 50 1.7, cosina 100mm - great lenses) K-x and 35 2.4 did not go well with each other (Focusing issues) and that was my forgotten gem in drawer.

And now i bought K-5 iis. 35 2.4 works perfect and IQ is crazy good. But i am not happy with my wide part. I need something wide which is close to 35 2.4 in terms of sharpness. On photozone.de I considered a 15mm ltd but it seems that 16-45 is shaper on wide end according to charts. Weird. Prime is not must have, but i want lens wich is sharper then 16-45 and with great AF. Any ideas ? Maybe sigma 17-70? 10-20? Tamron 17-50 (i heard about focusing issues with this lens?) Or ? Thank you

Where the 16-45 falls down on the test charts is it's chromatic aberrations... the Tamron 17-50 as reported by forum users is no worse than any other lens, according to the user reviews.

According to protozone the best score for a DA 15 in the centre is 2352 lw/ph and for the 16-45 2321 with the DA 15 being noticeable better edge to edge and every other way at ƒ8, so I'm not sure where the 16-45 is better.

At 24 mm the CA on the 16-45 is almost 3 pixels... the worst I've ever seen on any tested lens and easily capable of degrading image quality.. on the DA 15 it's less than a pixel, and probably not ever going to degrade IQ.

The Tamron at 17mm is rated excellent centre and edge, ƒ4 and beyond.

The Sigma at the low end 17mm , just isn't in the same ball park. The Pentax 17-70 looks acceptable at 17mm, but all the zooms have CA issues.

If you want that CA controlled, you're going to have to go with the prime.

The CA issue will have an effect on micro-contrast as noted above. The lens may not be sharper in lw/ph, but it will look sharper. I can see this even comparing the relatively cheap Tamron 90 with my much more expensive DA*60-250. If you look close, the Tamron has the edge in micro contrast.. but it all depends on how picky you're going to be. This is the usually the big issue in prime vs zooms. The new sigma zooms, Sigma 8-16 and 18-35 have made great strides at correcting CA and bringing the micro-contarst into prime quality, but at the cost of the addition of considerable size and weight.

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Last edited by normhead; 11-26-2014 at 09:32 AM.

[LensBeginner]

I'd say try to shoot a little stopped down and avoid the extremes of the focal range...
A camera with more MP and no AA filter will challenge both your lenses and your technique...

You'll probably see a difference more often, but it doesn't mean that you should do something about it: if you didn't see adifference before and now you see it, it means that you're resolving more than 12MP but less than 16... 12MP could still be enough depending on your intended use of the pictures you take.

So worry less, shoot more!

[luftfluss]

I need something wide which is close to 35 2.4 in terms of sharpness

A great 35mm lens will always be sharper than a great wide angle lens.

[SMeK]

I was happy with my k-x and adjusted AF to +130 for my 16-45 (lens is 6 year old and i am 3rd owner). On K-5 iis is inconsistent. On wide end i need +2 micro adjusment and on long end i need +6. I guess something is wrong with AF. Also front element have little scratch wich is only visible on bright and direct light like weird flare. On K-x everyting was good, seemed sharper due to lower resolution and less mpx. So I am thinking that little plastic fantastic 35 gave me anxiety and i want to replace 16-45 with something little sharper and better AF. So i need wide prime or zoom wich will give me better overall IQ. 16-45 will be on my K-x as backup body and lens. Tamron 17-50, Sigma 17-50, 17-70 or prime, 21, 15, or.. what?

[normhead]

I hate generalizations....
Sigma 8-16 at the edge ƒ8 lw/ph 2145
Canon EF 35mm f/2 USM IS - APS-C Format Review / Test Report - Analysis the edge ƒ5.6 2145

[luftfluss]

I hate generalizations....
Sigma 8-16 at the edge ƒ8 lw/ph 2145
Canon EF 35mm f/2 USM IS - APS-C Format Review / Test Report - Analysis the edge ƒ5.6 2145

Like I said...

[TER-OR]

Rent that 8-16 for a couple weeks and see if you don't get the fever too...now that it's so expensive on the used market.

I know it's a sarcastic (and ludicrous) comparison with a 35mm lens.

[luftfluss]

Rent that 8-16 for a couple weeks and see if you don't get the fever too...now that it's so expensive on the used market.

I know it's a sarcastic (and ludicrous) comparison with a 35mm lens.

I bet it is - I see people here rave about it all the time!

I just wanted to make the point to the OP - and I know you know this - that you have to compare like with like.

[normhead]

I bet it is - I see people here rave about it all the time!

I just wanted to make the point to the OP - and I know you know this - that you have to compare like with like.

I know how to fudge my results using DxO as much as anyone, so your point is countered, now what?



On DxO, the fastest lens always wins. They don't say much about who wins at a specific ƒ-stop.That's why I used the best performance at the lenses' best ƒ-stop... so I was comparing same agains same.

[maxxxx]

Hey,

I was very happy with 16-45 and my K-x. I also have 50-200, 35 2.4 a bunch of manual primes (Pentax M 50 1.7, cosina 100mm - great lenses) K-x and 35 2.4 did not go well with each other (Focusing issues) and that was my forgotten gem in drawer.

And now i bought K-5 iis. 35 2.4 works perfect and IQ is crazy good. But i am not happy with my wide part. I need something wide which is close to 35 2.4 in terms of sharpness. On photozone.de I considered a 15mm ltd but it seems that 16-45 is shaper on wide end according to charts. Weird. Prime is not must have, but i want lens wich is sharper then 16-45 and with great AF. Any ideas ? Maybe sigma 17-70? 10-20? Tamron 17-50 (i heard about focusing issues with this lens?) Or ? Thank you

The Sigma 10-20 and Pentax 12-24 are very nice, a lot of fun and relatively affordable used.

[TER-OR]

OK you want a wide zoom close to sharpness of a well-regarded prime? I'm tempted to be sarcastic.


Or just a wide lens - such as the 21mm suggested above? Perhaps the two wide zooms mentioned just above? I've never played with those, but I have with the 8-16 and I would not grab that if I want "normal" views ultra-sharp. That kind of lens is valuable for its unique perspective. I gather the 10-20 and 12-24 are more "normal."

"Prime is not must have, but i want lens wich is sharper then 16-45 and with great AF."

This should work: Sigma 18-35/1.8 Refurbished