[Conqueror]

FA 31 because lab tests aren't everything
Its qualities will be readily apparent when you own it

[D1N0]

You could also save a lot of money and take the DA 35 F/2.4 (although it's AF behaves poorly on my K-5 and I have to calibrate it all the time).

[clackers]

You could also save a lot of money and take the DA 35 F/2.4 (although it's AF behaves poorly on my K-5 and I have to calibrate it all the time).

Must be your copy, D1N0 ... it's been fine for me on K-30, K-S1 and now K-1.

[Edgar_in_Indy]

You could also save a lot of money and take the DA 35 F/2.4 (although it's AF behaves poorly on my K-5 and I have to calibrate it all the time).

I thought it was only your Sigma lenses that needed calibration? [Ducking for cover]

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Last edited by Edgar_in_Indy; 06-18-2016 at 07:33 AM.

[D1N0]

still on the list Edgar

[Edgar_in_Indy]

still on the list Edgar

[D1N0]

I get the feeling I am being trolled, should I take a peek? Or maybe this thread should get back on topic.

Must be your copy, D1N0 ... it's been fine for me on K-30, K-S1 and now K-1.

Could be. it is a cheap lens, could also be the combination with my k-5.....

[osv]

The lens will be used indoors at mainly anime conventions for cosplay photography, but will also occasionally be used for stuff like milky way shots.

35mm on ff is better for shooting people than 31mm on ff, but people have claimed that the sigma is actually wider than 35mm, so that may not matter so much.

the sigma 35mm art looks like it has good coma control, i'd be surprised if the fa31 can match that: Sigma A 35 mm f/1.4 DG HSM review - Coma, astigmatism and bokeh - LensTip.com

[Digitalis]

35mm on ff is better for shooting people than 31mm on ff

Say that sentence out loud with a straight face. The differences in FOV between 35mm and 31mm is trivial - however the differences in rendering between the two lenses is not. The sigma 35mm f/1.4 ART has a focal length of 34.2mm at infinity - it is important to note that internally focusing lenses are well known for focal length variance, especially as you approach MFD.

The lenstip reviewer doesn't test the entire imaging area covered by the lens in their coma test, and that is where the coma issues with the 35mm f/1.4 art become plainly visible, The transition point where coma dominates isn't subtle at all which can be problematic if you intend to use this lens for astro-landscapes. Though the FA31 has issues with Coma as well, on a subjective note: I don't find it to be as visually distracting as the coma from the 35mm ART.

[VoiceOfReason]

Wide open how good is the FA31?

[Digitalis]

Wide open how good is the FA31?

Excellent:


Pentax K-1 SMCP-FA31mm f/1.8 Limited ASPH -ISO 12800 1/30th f/1.8 [slight cropping and NR used]

Though Purple fringing can be problematic under harsh contrasty light, in those situations it is better to stop the lens down.

[osv]

Say that sentence out loud with a straight face. The differences in FOV between 35mm and 31mm is trivial - however the differences in rendering between the two lenses is not. The sigma 35mm f/1.4 ART has a focal length of 34.2mm at infinity - it is important to note that internally focusing lenses are well known for focal length variance, especially as you approach MFD.

a calculator showing the effect of if lenses: Optical formulas

so infinity vs. mfd? that's an interesting thought: "The Sigma doesn’t seem to be a true 35mm. It appears to be more around 32mm as compared to the others. I’m not sure how to verify this but when you overlay the images it is obvious." https://www.borrowlenses.com/blog/2013/10/four-35mm-lenses-compared-for-night-sky-photography/

he liked the coma as well.

i suspect that the trend is to make modern glass wider in order to leave room for in-camera lens corrections... some of the sony and batis lenses are like that.

if it was true 35mm vs. true 31mm, on ff, i'd definitely factor that difference into the decision, no question.

[Cannikin]

A few years ago I did a direct comparison of the FA 31 Limited vs the Sigma 35 f/1.4 Art in terms of bokeh. You can see it here: https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/226388-quic...1-limited.html

Most people seemed in favor of the FA 31's bokeh for its smoothness, especially in the focus transition area (only slightly out of focus areas). The Sigma has less longitudinal chromatic aberration ("bokeh fringing"), but has definite issues with hard edges in the background (can also be seen in many sample photos in reviews). It is very hard to make the FA 31 render unsmooth bokeh.

I have since sold the Sigma. It's a technically very good lens, definitely sharper and more well corrected than the 31 (especially with regards to purple fringing and LoCA), but it was huge in comparison, and shallower DOF (due to the larger aperture) doesn't make up for the bokeh quality IMO. I simply liked using and seeing the photos from the 31 more.

[VoiceOfReason]

Well, I traded the Sigma for an FA31 ltd, so I will get to see the pixie dust. When I put it up in the market place and posted my example RAW pics from the K1 I have 3 people interested, and the first one is who got it. I was surprised to have it happen as quick as it was, and I could have traded it for either lens, but I went with who messaged me first.

So, will I see pixie dust when using it with the K1?

---------- Post added 06-23-16 at 10:45 AM ----------

Excellent:


Pentax K-1 SMCP-FA31mm f/1.8 Limited ASPH -ISO 12800 1/30th f/1.8 [slight cropping and NR used]

Though Purple fringing can be problematic under harsh contrasty light, in those situations it is better to stop the lens down.

Looks like I might be pretty happy with it then!