[Kangaxx]

Hello, as the title states I'm considering about selling the DA 21 I own and to buy in its place the Sigma 17-50, but I want to hear some advices before since I'm not really an expert.
I'm considering to sell it because I shoot more than often at private parties. I can do with my Pentax DAL 18-55 f/3.5-5.6, but I end up using the DA 21 and 50 prime lenses for better results.
But of course I dream about how confortable the 18-55 is and the wiiiiide shoots I got at 18, so the 17-50 seems the obvious choice since it can open 2/3 of a fstop more.
But I'm afraid that the performances in terms of sharpness, flare control, distortion and vignetting could be far worse in these zoom lenses. Still it should be noticed that 21 is enough far from 17 to avoid the worst. If anyone happens to own both, I'd love a comparison picture at 21mm.
I'd also consider the Sigma 18-35 f/1.8, but the focusing issues on Pentax, limited zooming range and availability keep me from considering it.
I should mention that the 21mm lens is really really compact compared to the 17-50, I swear the 21 is so small I forgot it in my jacket pockets after a party, it's really comfortable to bring around to switch it. But if I can do with a single lens kit it's even better than having a small one.
So? Should I worry about the difference in performances between the two? Obviously, at 21mm only.

[BigMackCam]

I own both lenses. IMHO, each is excellent in its own right, but for different reasons.

Starting with the Sigma 17-50 f/2.8, it has a versatile focal length range and is very usable at f/2.8. But it's quite big and heavy for an APS-C lens. AF performance - at least on my copy, when paired with my K-3 / K-3II and earlier cameras - is best described as "reasonably good". I'm in the habit of auto-focusing once, then a second time, to make sure it's absolutely spot on. That's not a problem for me, but I'm aware of having to do it, and it's not ideal if you're shooting moving subjects at wider apertures. The near-silent DC AF motor is a welcome bonus, though. And I really like how sharp and detailed this lens is from edge-to-edge. Really quite impressive, especially for a zoom. And yet... I find the rendering to be somewhat "clinical", by which I mean, my perception is that it doesn't lend much of its own character to photos. I don't feel any "magic" coming from the lens. That's not a criticism of it, but merely a personal observation. I haven't had any real problems with flare control, though I do notice some lateral chromatic aberration at wider focal lengths. But it's correctable in post-processing.

And now the DA21. I have the HD rather than the SMC version, but in most respects my views should be relevant to both. The HD DA21 is one of my favourite Pentax lenses (and undoubtedly my favourite DA Limited). It may not be as edge-to-edge sharp as the Sigma at wider apertures, but the rendering has so much more character to my eye. It adds something over and above my own composition and choice of lighting that the Sigma doesn't. Plus it's compact, light, all metal in construction, and the AF is always spot-on first time, even if the screw-drive is a bit noisy.

I think it's really difficult for to choose between the two. It really depends on your use cases. At 21mm, for me, the DA21 runs rings around the Sigma 17-50 f/2.8 because of its rendering. It has character, and that counts for a lot in my book. But the Sigma, whilst less characterful and much bigger / heavier, offers an awful lot of versatility. Only you can decide which is more applicable to your needs

I wouldn't want to choose... I'd rather keep both, for different applications. If I was forced to pick one, though, I'd grudgingly go with the Sigma 17-50 f/2.8 for versatility alone. But my heart would forever wish that I'd kept the DA21 for those situations where it's applicable

[Kangaxx]

I feel what you say about the composition of the DA 21. Its brokeh is odd, it's soft and lovely but it's odd in a way that gives prominence to your subjects. And if they are at the center of the picture, they seem like "floating" over the blurry background.
And this is why I am here, I love that.
Thing is I don't usually use it for portraits at those parties, I use it for getting the whole full room of people, for portraits I tend to prefer the DA 50. Expecially at parties, f/1.8 helps to give some brokeh when there's little space before the background.
I think I will have to think about it and try some portraits with the DA 21.

[Cambo]

Hello, as the title states I'm considering about selling the DA 21 I own and to buy in its place the Sigma 17-50, but I want to hear some advices before since I'm not really an expert.
I'm considering to sell it because I shoot more than often at private parties. I can do with my Pentax DAL 18-55 f/3.5-5.6, but I end up using the DA 21 and 50 prime lenses for better results.
But of course I dream about how confortable the 18-55 is and the wiiiiide shoots I got at 18, so the 17-50 seems the obvious choice since it can open 2/3 of a fstop more.
But I'm afraid that the performances in terms of sharpness, flare control, distortion and vignetting could be far worse in these zoom lenses. Still it should be noticed that 21 is enough far from 17 to avoid the worst. If anyone happens to own both, I'd love a comparison picture at 21mm.
I'd also consider the Sigma 18-35 f/1.8, but the focusing issues on Pentax, limited zooming range and availability keep me from considering it.
I should mention that the 21mm lens is really really compact compared to the 17-50, I swear the 21 is so small I forgot it in my jacket pockets after a party, it's really comfortable to bring around to switch it. But if I can do with a single lens kit it's even better than having a small one.
So? Should I worry about the difference in performances between the two? Obviously, at 21mm only.

Zoom Schmoom...get a 40 Limited and save your pennies for a 70. All three smaller than the Sigma, whose lenses I have not liked since my friend got a 300 F2.8 with the front element taped in place.

Sigma Schmigma.

Here's a portrait with the 40 f2.8..handheld in a nightclub, available lighting...



You already know how wonderful the 21 is. The Sigma zoom is bound to be a letdown after that amazing lens. Maybe since you hav the 50, get the 70 first; more working distance from the subject.

Cheers,
Cameron

[mikesbike]

I also have both. This Sigma f/2.8 zoom lens is a wonderful choice for this type of lens. Great for low light use, for situations needing a higher shutter speed, and just for an all-around zoom lens where you might need its aperture capability. A sharp zoom lens. Not real big or heavy, but substantial.

But for the kind of circumstance you are talking about, I don't use either. My favorite for that is my DA 18-135mm. With it I can capture a large gathering of people with its wide-angle, or I can zoom to frame a smaller group within the overall group, or I can zoom in to single out an individual. What I am saying is, doing all this in getting candid shots from a distance to capture people in their natural state of facial expressiveness and physical attitudes. People are then unaware of the photos being taken, and when later they see them they are usually surprised and enjoy them even more. Sharpness is excellent basically throughout in the central part of the frame. Between 18-50mm the edges are pretty good as well, especially if stopped down a little.

And if singling out an individual, at the longer FL, you don't need f/1.8 to blur background, nor do you need good edge performance. In fact, the edge softening actually enhances bokeh.

In your case, however, if you are working in closer quarters, and you've found the DA 21mm LTD and 50mm prime lenses have been working well for you in terms of better sharpness than your short zoom lens, except you need greater wide angle while still getting superior sharpness, the Sigma f/2.8 zoom lens might be just the thing for your specific need.

I would not sell the DA 21mm LTD, however. It is too good as a versatile, very compact all-around prime lens. Good reasons that I still have mine.

[Desperado]

Sigma 17-50 is realistic,Da limiteds are artistic.(in terms of microcontrast and color rendition)but the difference is very minor,only keen users can be aware of that fact.

[Jonathan Mac]

Both are very good lenses but you shouldn't worry about the IQ of the Sigma - it's very good indeed. The zoom will provide a lot of flexibility for parties and it's slightly faster to boot.

[Kangaxx]

I also have both. This Sigma f/2.8 zoom lens is a wonderful choice for this type of lens. Great for low light use, for situations needing a higher shutter speed, and just for an all-around zoom lens where you might need its aperture capability. A sharp zoom lens. Not real big or heavy, but substantial.

But for the kind of circumstance you are talking about, I don't use either. My favorite for that is my DA 18-135mm. With it I can capture a large gathering of people with its wide-angle, or I can zoom to frame a smaller group within the overall group, or I can zoom in to single out an individual. What I am saying is, doing all this in getting candid shots from a distance to capture people in their natural state of facial expressiveness and physical attitudes. People are then unaware of the photos being taken, and when later they see them they are usually surprised and enjoy them even more. Sharpness is excellent basically throughout in the central part of the frame. Between 18-50mm the edges are pretty good as well, especially if stopped down a little.

And if singling out an individual, at the longer FL, you don't need f/1.8 to blur background, nor do you need good edge performance. In fact, the edge softening actually enhances bokeh.

In your case, however, if you are working in closer quarters, and you've found the DA 21mm LTD and 50mm prime lenses have been working well for you in terms of better sharpness than your short zoom lens, except you need greater wide angle while still getting superior sharpness, the Sigma f/2.8 zoom lens might be just the thing for your specific need.

I would not sell the DA 21mm LTD, however. It is too good as a versatile, very compact all-around prime lens. Good reasons that I still have mine.

You got the point here, 21 renders wonderfully but I have to go so close to the subject they are going to pose for the picture, and I'd rather avoid it.
Also, I'd prefer to avoid 18-135, it costs a lot and it performs similarly to the DAL 18-55 which I found myself discarding when possible.
I think you guys are convincing me to wait a bit and get to own both...
But I just got the DA 55-135, I have to calm down :-)

[rogerstg]

But I just got the DA 55-135, I have to calm down :-)

Assuming you mean the DA* 50-135, have you considered it's brother DA* 16-50 f/2.8? It's my go-to lens for house parties and close quarters and has served me well for a decade, though I'm not a pro. There's one for sale in the marketplace for $250. As always, caveat emptor.

[Kangaxx]

To whoever may concern, I realized how much I would have missed the DA 21 Limited so I ended up getting a DA 15 Limited for my wide angle needs.
And I realized that I got way more than just a compact wide angle prime lens with great IQ, the closeups it delivers are just lovely.
Also, shooting at parties with all my gear in a bag, I realized that big zooms are way more impratical than small primes. Having to switch between two big zooms is horrible, with primes you switch more often but it's way more fast and comfortable to do.

[BigMackCam]

To whoever may concern, I realized how much I would have missed the DA 21 Limited so I ended up getting a DA 15 Limited for my wide angle needs.
And I realized that I got way more than just a compact wide angle prime lens with great IQ, the closeups it delivers are just lovely.
Also, shooting at parties with all my gear in a bag, I realized that big zooms are way more impratical than small primes. Having to switch between two big zooms is horrible, with primes you switch more often but it's way more fast and comfortable to do.

Very pleased to see you've found a solution. The DA15 Limited is an outstanding lens - enjoy it!

Should you ever want coverage at the "normal" through "short tele" range, all of the other DA Limited lenses are excellent too - the DA35 Macro, DA40 and DA70. It sounds like you're sorted for now... but any and all of these other lenses will admirably match your DA15 and DA21 for longer work

[Kangaxx]

Very pleased to see you've found a solution. The DA15 Limited is an outstanding lens - enjoy it!

Should you ever want coverage at the "normal" through "short tele" range, all of the other DA Limited lenses are excellent too - the DA35 Macro, DA40 and DA70. It sounds like you're sorted for now... but any and all of these other lenses will admirably match your DA15 and DA21 for longer work

I have only the wide angle as limiteds, aside from that I have a DA 50 and a DA 50-135. I'm sorted, yes, but I know one day I will fall for the DA35.