[VoiceOfReason]

I've been selling some of my lenses and am gearing up for a purchase. I have a few different notions about what I might be looking for, but would love some input from some of you who have owned lenses in this range.

My cameras are K5ii and an 70s MX SLR. I enjoy having lenses that work on both formats, but it's not an absolute. Lenses that I'm keeping include:

DA 18-135 WR
FA 35/2
SMC 50/1.4
Tokina AT-X 90/2.5
Tokina AT-X 100-300/4

Things I value include:
Build quality. I really struggle with flimsy plastic lenses.
I do enjoy small primes, but am not ruling out a fast zoom. Big, bulbous primes however, seem like the worst of both worlds to me.
Image quality, of course
Speed. For indoor shooting without a flash on my dSLR, I notice a big difference between 2.8 and f2. I struggle to get exposure in a lot of circumstances with a 2.8 lens, but the FA35 is almost always fast enough.

I really, really enjoy the 24mm focal length on both dSLR and film formats. It's almost magic for me, usually for photographs like this one:



...even though it was taken at 35mm. Something intimate in the foreground and an opening perspective behind it. Also, Seattle is compact, crowded and dark, so speed and wideness help. It's also useful, of course, for things like cityscape, which I also enjoy.

So, what's on my mind is:
FA* 24/2 - It gets some mixed reviews, love it or hate it. I don't know if that's a model varience issue or preference. I like the specs on it and I enjoy a lot of the posted pictures I see from it.
SIGMA 20/1.8 or 24/1.8 - They don't get a lot of love and they're bigger, but they're also faster, cheaper and more readily available. Any opinions?

Or a fast zoom. Something in the 18-50/2.8 range. The SIGMA 24-60/2.8 comes up now and again. There are also things like the Tamron 28-70/2.8, which doesn't quite get me to 24mm, but it does also give me an autofocus lens longer than 35mm at f2.8, which I would enjoy for different things, like little kid's basketball games and things.

You can see a pattern with me of Pentax and Tokina AT-X lenses. The AT-X autofocus 20-35/2.8 and 28-70/2.8 get my attention when they come up.

The thing with 2.8 zooms (and primes for that matter) is that I feel like they just barely give me the speed I need, so when I read that they get usable at f4 and start looking sharp at 5.6, I think I would feel like it was a failed purchase. Then again, I'm never quite sure what to think of those comments.

So, any opinions, experiences and advice will be appreciated.

I may sell one more lens before I get serious about buying, unless something falls in my lap, but I'd like to narrow my hunt.

Troy

The Sigma 24-70 f/2.8 HSM is great, sharp even wide open. I had the Sigma 20 f/1.8 and I sold it. I didn't really care for it. If you're fine with APSC only the Sigma 18-35 f/1.8 is great.

[ChristianRock]

The Sigma 24-70 f/2.8 HSM is great, sharp even wide open.

It's also huge with an 82mm filter thread... The 24-60mm also by Sigma seems more manageable but also more rare... Neither one could be called a street photog's lens though!

[Nicolas06]

To me the FA*24 (I have it, plan to resell) is really great... at f/5.6 and f/8. Sharp borders to borders. And it make the subject pop. My issue with it, is that for my case, I find it too heavy toward what it offer and so I think I like the DA21 more. You get less pop maybe, and a bit less sharpness border at f/8 but it is small and light and overall much better flare resistance and constrast in contra light.

At f/2 the lens isn't great at all. Let say it take the shoot. I would try to avoid it bellow f/4 but I'am more after landscapes than bokeh for such focal length so maybe yit would work better for you at f/2 than me...

In term of zoom, there no contest that for your requirement, you want that heavy and big 18-35 f/1.8. It would not work on FF. It is sharp at all appertures, gather lot of light, let you choose your framing and help you get 1.2-1.3 EV more than an f/2.8 zoom. The price is high compared to 1 prime but the sharpness you'll get will be really better. The issues to find with the 18-35 are a bokeh that is not at the level a good prime would give (like the FA35) and to get perfect AF.

[troika]

To me the FA*24 (I have it, plan to resell) is really great... at f/5.6 and f/8. Sharp borders to borders. And it make the subject pop. My issue with it, is that for my case, I find it too heavy toward what it offer and so I think I like the DA21 more. You get less pop maybe, and a bit less sharpness border at f/8 but it is small and light and overall much better flare resistance and constrast in contra light.

At f/2 the lens isn't great at all. Let say it take the shoot. I would try to avoid it bellow f/4 but I'am more after landscapes than bokeh for such focal length so maybe yit would work better for you at f/2 than me...

...

This is what concerns me about the FA*24. If it's not useful at f2, then it's in no way worth it. Even if it sharpened up at 2.8, then it might, but but this experience worries me off of the investment it would take.

However, this experience seems about equally common:

The FA*24 is very nice. Mine is quite sharp wide open (and excellent from f/2.8), and the colours are gorgeous. It is a pretty solid lump though, and the AF is a little jittery.

...

I never know quite what to make of that. Copy variation or opinion? No way to know except spend $400-500 to find out, maybe test a few to find the one that works for you on your camera? Not practical.

[Nicolas06]

I never know quite what to make of that. Copy variation or opinion? No way to know except spend $400-500 to find out, maybe test a few to find the one that works for you on your camera? Not practical.

Photozone tested the lens:

Pentax SMC-FA* 24mm f/2 AL [IF] - Review / Lab Test Report - Analysis



From the 18-35 f/1.8 test: Sigma 18-35mm f/1.8 DC HSM | A ("Art") - Review / Test Report - Analysis the 18-35 is more uniform at 24mm f/1.8 than the FA*24 is at f/8

To me, let say at f/2 it would work for a subject near the center and were the borders at large are out of focus. It would be visibly soft if anything on the border is in focus at f/2 and f/2.8 meaning that you should not try it for a a low light scene were you want everything sharp.

The DA21 is better or as good in resolution at all the common appertures:



To me you use the FA*24 for it's special rendering and hability to make the subject pop. I find 24mm too short for some portraiture and some bokeh shoot but in that we differ. You may like the portraiture capabilities at wide angle.

But really I think that the 18-35 f/1.8 does the job better and is the best compromize if you need a fast lens covering 24mm with AF in pentax mount.

At worst the sigma 24mm f/1.8 keep corners as weak as the FA*24, but the border are significantly better and the lens is a bit faster. To me it would be able to do a great job for the bokeh shoot at 24mm and the 24mm night shoot at f/1.8 would look acceptably sharp on a wider part of the frame.

[troika]

That sort of helps a bit, thanks. It still doesn't quite reconcile for me why some people report "great from wide open" and others say "unusable wide open". Unless either their expectations are different going in or there's copy variation.

Generally with tests, especially of vintage lenses, I don't assume that they tested 5 copies and gave the average.

It is a good data point, though. I'll give it some thought. I really appreciate all the input I'm receiving.

[Nicolas06]

That sort of helps a bit, thanks. It still doesn't quite reconcile for me why some people report "great from wide open" and others say "unusable wide open". Unless either their expectations are different going in or there's copy variation.

Generally with tests, especially of vintage lenses, I don't assume that they tested 5 copies and gave the average.

It is a good data point, though. I'll give it some thought. I really appreciate all the input I'm receiving.

To me photozone and my experience match. Klaus recognize the lens contrasty and I recognize the lens make the subjects pop. To me really the FA*24 is not a bad lens, it is great because of that property. But this is not say a lens that does everything well, in particular not at all appertures.

We could have got 2 bad copies, sure. But I think this is not that. My lens is sharp closed down and give then great results.

To me different people have also different level of expectations. I don't know were are your expectations. Me I have only primes right now and 2 in my bag are extremely sharp: DA35 ltd, FA77. The DA21 is sharp but the field curvature can be anoying. That's the same with the DA15. In your case your low light shoot really doesn't show much details so you should be able to take something as good I think.

If really low light performance was key to me and I'd wanted a set of light primes not needing much a tele, then I'd consider A fuji with say 23mm f/1.4...

[troika]

The photo in my original post is not what I would call "sharp", but it's very pleasing and I'm not sure that I would want it to be critically sharp. This is the kind of clarity that I would hope to get in similar situations.

I really do appreciate your help. I just listed another lens for sale and am going to take my time to consider what to add.

[dadipentak]

I know I'm not as discriminating as some (and I do think I got a good copy) but I really (as in, "really really") like my Sigma 18-35/1.8.