[Irematic]

Looking to get a wide-normal lens mostly for indoor portraits and some close-up non-macro work. I don't place any value in bokeh or lens character or fairy dust, just looking for whatever is going to deliver the best optical image quality- sharp as possible with minimal CA

So far, looking at:
43mm 1.9 Limited
Sigma 35mm 1.4 HSM A
35mm 2.0 HD
31mm 1.8 Limited

Leaning towards the Sigma based on my past experiences with both Sigma and Pentax optics but wanted to check to make sure I wasn't missing anything here.

Thanks

[wadge22]

The new Irix 30mm may well be worth a look, as long as manual focus isn't a disqualifier.

[ChristianRock]

According to your requirements I would say the Sigma 35 1.4 Art.

[vector]

If sharp and lifeless are the requirements then why not the plastic fantastic DA 35mm f2.4? People describe it as clinical all the time. Stop it down to F8 to get rid of that bokeh and you'll be shooting with razor blades, not to mention it's very affordable. My answer may come across a little fecetious and it kind of is, but also serious... I have 2 copies of that lens and it is what your stated requirements are asking for.

[BigMackCam]

I think the HD FA35/2 would suit your requirements well. It's far from lacking in character, but it's very sharp and CA is well-controlled. It handles flare and ghosting really well, too, which should be a consideration for indoor portraits where you might have quite strong light-sources such as ceiling, floor and table-lamps (the Sigma 35/1.4 Art doesn't do so well here). It's also small, light but solid, and very inexpensive for the optical quality (especially if you buy it when discounted, which seems to happen quite frequently). It's just a really good lens all round...

[Kozlok]

We’re you, I would look at Flickr lens pools for each lens, decide which YOU like the best. What do you mean by sharp? Center sharpness? Across the frame evenness? Each of those lenses is sharp. At some point if all the lenses are sharp enough, something else matters more. Contrast, flare, bokeh, colors.

Buy any one of them from a good shop. Return them if you don’t love them. Each of them is the right one for someone.

[Ash]

There are a LOT of sharp lenses in the 30-50mm range, although it wasn’t clear if you were shooting FF or APS-C, as it would make a difference as to whether you want wide-normal for FX or DX format. If budget weren’t an issue, certainly the HD 35/2 and HD 31/1.8 would be top choices for sharpness, regardless of what “pixie dust” exists in either lens. Both are quality builds and would last generations, as opposed to the plastic fantastic 35/2.4, which is optically excellent but is of more disposable build quality.

[UncleVanya]

I think the HD FA35/2 would suit your requirements well. It's far from lacking in character, but it's very sharp and CA is well-controlled. It handles flare and ghosting really well, too, which should be a consideration for indoor portraits where you might have quite strong light-sources such as ceiling, floor and table-lamps (the Sigma 35/1.4 Art doesn't do so well here). It's also small, light but solid, and very inexpensive for the optical quality (especially if you buy it when discounted, which seems to happen quite frequently). It's just a really good lens all round...

My expertise with the smc version is also excellent. The fa 35 is sharper on the edges than the 31 but slightly weaker in the center. It’s a very good lens. The da 35 plastic fantastic was competent but not as special for whatever reason. Perhaps it’s my own bias. I’ve never used the Sigma.

[Digitalis]

just looking for whatever is going to deliver the best optical image quality- sharp as possible with minimal CA

This is under the presumption you will have the lens stopped down? In that case at f/8 pick any of those lenses you have listed, they are all good. Not much point in shelling out for an f/1.4 lens if you're only going to use it at f/8~f/11 the Pentax 35mm f/2 HD would be the ticket.

[BigMackCam]

This is under the presumption you will have the lens stopped down? In that case at f/8 pick any of those lenses you have listed, they are all good. Not much point in shelling out for an f/1.4 lens if you're only going to use it at f/8~f/11 the Pentax 35mm f/2 HD would be the ticket.

Actually, whilst the Pentax 35/2 performs extremely well at f/8 - f/11, it peaks at f/4. It's very good even at f/2.8... so, for the indoor use-case specified by the OP, I think it fits the bill nicely.

[tokyoscape]

sharp as possible with minimal CA

The sharpest normal FA I have ever used or test is FA50 f2.8 macro and it is not on your list!
F50 and DFA 50 f2.8 marcro said to have the same optic with similar sharpness.
If any of them is a WR lens, I would drop my DA*55 in a heartbeat.

[Cerebum]

Are you shooting full frame or APSC? if its the latter the 35mm f2 is a peach. It is sharp and not too expensive. Its main flaw is corner softness which the sensor crops out, so, no problems. The 31 and sigma art also get rave reviews but I don't have either. The da* 55m f1.4 tops my list but it may be a bit long for your needs

[Medex]

From your list Sigma Art is sharpest wide open.
FA 31 is already very good at f2.8. Excellent at f4. Same for FA43. Both are a little soft at f1.8-2.0.
Sigma Art zoom 18-35 is very sharp lens. Bigger but more versatile. Sharpness is not weeker compared to Sigma Art 35 in ehole range of apertures.

[BigMackCam]

From your list Sigma Art is sharpest wide open.
FA 31 is already very good at f2.8. Excellent at f4. Same for FA43. Both are a little soft at f1.8-2.0.
Sigma Art zoom 18-35 is very sharp lens. Bigger but more versatile. Sharpness is not weeker compared to Sigma Art 35 in ehole range of apertures.

It's worth mentioning that several people have had AF accuracy issues with the 18-35 on K-mount (and Canon EF too, I believe)... not everyone, but it's a well-known complaint nonetheless (same with the 30/1,4 Art that I use and love on APS-C - though I've not noticed any significant issues with my copy).

[pschlute]

If wide open low CA is a requirement then avoid the 31mm LTD. It will depend on your lighting of course, but the lens does suffer from it.