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SMC Pentax-FA 31mm F1.8 AL Limited Review RSS Feed

SMC Pentax-FA 31mm F1.8 AL Limited

Reviews Views Date of last review
85 324,547 Fri August 2, 2019
Recommended By Average Price Average User Rating
95% of reviewers $876.11 9.51
SMC Pentax-FA 31mm F1.8 AL Limited

SMC Pentax-FA 31mm F1.8 AL Limited
SMC Pentax-FA 31mm F1.8 AL Limited
SMC Pentax-FA 31mm F1.8 AL Limited

This Limited lens features all-metal barrel and a built-in hood. It is known for delivering exceptional wide-angle image quality.

SMC Pentax-FA 31mm F1.8 AL Limited
©, sharable with attribution
Image Format
Full-frame / 35mm film
Lens Mount
Pentax K
Aperture Ring
Yes (A setting)
Automatic, 9 blades
9 elements, 7 groups
Mount Variant
Check camera compatibility
Max. Aperture
Min. Aperture
AF (screwdrive)
Min. Focus
30 cm
Max. Magnification
Filter Size
58 mm
Internal Focus
Field of View (Diag. / Horiz.)

APS-C: 50 ° / 42 °
Full frame: 70 ° / 60 °
Dedicated pouch
Lens Cap
Dedicated metal push-on
Weather Sealing
Other Features
Diam x Length
65 x 68.5 mm (2.6 x 2.7 in.)
345 g (12.2 oz.)
Production Years
2001 to present (in production)
$896 USD current price
$880 USD at launch
Engraved Name
smc PENTAX-FA 1:1.8 31mm AL Limited
Product Code
20280 (silver), 20290 (black)
User reviews
In-depth review
One aspherical element, one ED element, one high refraction low dispertion element.

Black and silver

Screwdrive AutofocusBuilt-in HoodAperture RingAutomatic ApertureFull-Frame Support
Purchase: Buy the SMC Pentax-FA 31mm F1.8 AL Limited
In-Depth Review: Read our SMC Pentax-FA 31mm F1.8 AL Limited in-depth review!
Sample Photos: View Sample Photos

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Site Supporter

Registered: December, 2014
Location: Colorado
Posts: 434
Lens Review Date: August 2, 2019 I can recommend this lens: Yes | Price: $600.00 | Rating: 9 

Pros: Sharp, compact, nicely built
Cons: Cap (too much friction to take it off)
Sharpness: 10    Aberrations: 7    Bokeh: 9    Autofocus: 9    Handling: 10    Value: 10    New or Used: Used    Camera Used: K1   

Acquired this lens about two weeks ago. I do not have much more to add to the already excellent reviews here.

The characteristics of the lens is that at large apertures (to about f5.6) it is sharp in the center but less along the edges and in the corners. This is not saying that edges and corners are not good. It is just that they are noticeably not as good as the center. At large apertures edges and corners of K28/3.5 are actually a bit better. Close down to f8 this lens becomes corner-to-corner sharp. No matter what you do with the lens, wide-open closeups or close-down sceneries, you will not be disappointed.

I really like this lens. I consider this lens far superior to all 28mm lenses that I have used including the already excellent Vivitar 28/1.9 and K28/3.5.

NOTE: On APS-C it is probably corner-to-corner sharp at all apertures except the largest ones.
Site Supporter

Registered: December, 2009
Location: Christchurch, New Zealand
Posts: 1,426

1 user found this helpful
Lens Review Date: April 26, 2019 I can recommend this lens: Yes | Price: $530.00 | Rating: 10 

Pros: Relatively small, lovely OOF rendering, great colours, great sharpness, wonderful build
Cons: Nothing significant
Sharpness: 9    Aberrations: 9    Bokeh: 10    Autofocus: 8    Handling: 10    Value: 8    New or Used: Used    Camera Used: K-1   

Overall I love this lens. It has some very nice qualities to it that make it a real pleasure to use. I was lucky to get a used one that is in near mint condition and pretty reasonably priced.

Prior to getting this lens my go to wide was the FA 35 f2, which is a great compact lens. Compared to the FA31:
  • FA31 has a much nicer build than the FA35
  • My FA31 copy is slightly sharper than my FA35 (especially across the frame)
  • FA31 bokeh is significantly improved over the FA35 in the focus transition zones
  • Obviously the FA31 is little bit faster than the FA35 but still totally usable wide open
  • FA31 is quite noticeably wider the FA35 (no surprise there and may be a plus or minus for you)
  • Both have quite attractive flare stars when stopped down a bit (although FA31 is busier with more points to the star)
  • FA35 is smaller and lighter
  • FA35 is lot cheaper than the FA31
I also have a FA28 but I find the FA31 is near enough to that focal length for my use and so I have not had much need for 28mm. In fact for my use I find 31mm a nice compromise between 28mm and 35mm and so carry one less lens (your use may differ).

In summary if you have the budget for the FA31 (or lucky to get a deal on one), then go for it, otherwise the FA35 is fantastic value (and I'm having trouble letting mine go!).

Wide Open:

At f8:

Stars at f13:
Site Supporter

Registered: December, 2018
Location: Vancouver Canada
Posts: 29

4 users found this helpful
Lens Review Date: February 23, 2019 I can recommend this lens: Yes | Price: N/A | Rating: 7 

Pros: Great for low light
Cons: Terrible CA in harsh light!
Sharpness: 9    Aberrations: 5    Bokeh: 10    Autofocus: 9    Handling: 8    Value: 6    New or Used: Used    Camera Used: K1   

I was very excited to have an opportunity to borrow a AIV 31mm from a colleague at work for several weeks. I own a FA 35 f2, the FA Limited 77, and the DA HD 20-40 Limited (APS-C) as well.

This review is a comparison of the 31, 35, and 20-40 lenses on the K1.

Image quality
The 31mm is very very good in low-to-soft light, and the bokeh is in a completely different class from the FA 35mm than I would have imagined. Exposure metering is better on the 31mm too. Low light, shallow DOF appear to be the strengths of this lens, and it makes for a good portrait lens.

Sharpness of the 31mm and 35mm were equal. I could not detect a difference.

In harsh light, the 31mm showed massive purple fringing in high contrast areas; as bad as the FA 35. Given the reputation of this lens, I am really disappointed.

Another surprise: the DA limited 20-40 [zoomed to 31mm f3.5] on the K1 was nearly as sharp as the FA 31mm at 3.5! The FA 31 has much less vignetting of course; but what surprised me was how usable images with 20-40 are on full-frame.

The 31mm is solid and enjoyable to use; and on a APS-C body nicely balanced. The K1 however is already heavier than I would like, and I prefer the lighter plastic weight of the FA 35. T he 31mm made it impossible for me to shoot the K1 a single-hand.

The 31mm is a great lens, but is it worth the significant cost over the FA 35? For me, it would have to be significantly better than the FA 35 and even the DA 20-40 (which I am now using with the k1). With serious CA in harsh lighting, I hesistate to use this lens outdoors on a bright day. Perhaps a future 31mm with HD coatings will appear, and then the value equation will improve.
Site Supporter

Registered: January, 2013
Location: San Luis Obispo
Posts: 146
Lens Review Date: October 5, 2018 I can recommend this lens: Yes | Price: N/A | Rating: 10 

Sharpness: 10    Aberrations: 7    Bokeh: 10    Autofocus: 9    Handling: 10    Value: 9    New or Used: Used    Camera Used: K-1   

Best Lens of All Time (That you can easily afford).
This is my main walk around lens, 31mm is excellent for travel photography. This lens is also small and light to handle.
Snappy AF on K-1, Below F2.2 it is ultra sharp. Unmatched color and unmatched bokeh. Sigma 35mm/1.4 fails on the latter 2 points, it is only sharp, but in today's world, sharp is cheap.

Registered: December, 2013
Posts: 489

1 user found this helpful
Lens Review Date: June 16, 2018 I can recommend this lens: Yes | Price: $900.00 | Rating: 10 

Pros: Small, light, fast, sharp
Cons: Not 49mm filter thread like the 43 and 77, not WR, inbuilt hood
Sharpness: 10    Aberrations: 9    Bokeh: 9    Autofocus: 9    Handling: 9    Value: 7    New or Used: Used    Camera Used: KP, K-30, PZ-1p   

The image quality of this lens is perfect. A little prone to flare and makes a little PF, but easy to ceoorect these by a little recompose or in post production. This is my third most used lens after the DA*16-50 and DA*55. In the pentax system only the Sigma 35 F1.4 Art is near in focel lengt and image quality, but that lens is much bigger.
The lens has an inbuilt hood which prevents using step up rings or simple filter systems. The other two FA limiteds has 49mm filter thread so I can share filters among that, but the FA31 needs bigger filters.

Here are some examples:
IMG180422_0022 by Benjámin Czétényi, on Flickr

IMG180428_0352 by Benjámin Czétényi, on Flickr

IMG180428_0349 by Benjámin Czétényi, on Flickr

IMG180505_0058 by Benjámin Czétényi, on Flickr

This one is a cross eye 3D image:
IMG180505_0061 by Benjámin Czétényi, on Flickr
New Member

Registered: June, 2017
Posts: 2

4 users found this helpful
Lens Review Date: November 4, 2017 I can recommend this lens: Yes | Price: $750.00 | Rating: 10 

Sharpness: 9    Aberrations: 8    Bokeh: 10    Autofocus: 10    Handling: 10    Value: 10    New or Used: New    Camera Used: KP   

As a long-time Pentax user I got little annoyed by the acclaimed "legendary" status of this lens, and felt no urge to fill the gap between my two most used leses, DA21 and FA43. Both lenses show their quality even better with the brilliant new KP sensor. But curiosity prevailed when I saw a mint silver made-in-Japan FA31 for sale. For a Limited lens it is bigger and heavier than what I was used to. But after the first day of shooting in the streets of Amsterdam, I was "sold" completely. It has exactly the same thing that makes Leica lenses (I used an M9 for some time) so special ! Numerous people have tried to explain what that is. It's price may be an issue, but look at the "mirrorless" world today, where top grade primes are mostly priced well over 1K, and have sizes that dwarf the camera body. This piece of heavy metal balances very nicely on the little KP (also aesthetically)
New Member

Registered: June, 2015
Posts: 17

1 user found this helpful
Lens Review Date: October 16, 2017 I can recommend this lens: Yes | Price: $600.00 | Rating: 10 

Pros: Size, build, design, sharpness, bokeh.
Cons: A bit soft wide open, but so what.
Sharpness: 10    Aberrations: 8    Bokeh: 10    Autofocus: 10    Handling: 10    Value: 10    New or Used: Used    Camera Used: K-5iis   

I love this lens! It is a masterpiece of design and one of the lenses that drew me to the Pentax system in the first place. I thought besides Leica, no one makes lenses that cool. It is quite small and built so solidly that it inspires a sense of confidence while using it, as well as a feeling of durability, and like all great products, just feels good to hold.

It performs amazingly, but from f2.8 to f5.6 on APSC it is really special. Razor sharp with stunning bokeh, and a smoothness to the render that is very appealing. I cannot recommend it enough .
Junior Member

Registered: January, 2013
Location: Texas
Posts: 32

1 user found this helpful
Lens Review Date: June 13, 2017 I can recommend this lens: Yes | Price: $775.00 | Rating: 9 

Pros: I.Q. at f/2.8, Mechanical marvel
Cons: I.Q. at f/1.8, No quick shift
Sharpness: 9    Aberrations: 9    Bokeh: 9    Autofocus: 9    Handling: 9    Value: 8    New or Used: Used    Camera Used: Pentax K70   

On the negative side, the price, the lack of quick shift, and an unacceptable Image Quality at full aperture: the entire field is veiled.
Also, it is a little bit heavy.
But the I.Q. is stunning, and I mean stunning, at f/2.8 and above! Better on the edges than a Leica R 28/2.8 or a Nikon 28/2.8 AIs, and similar at the center!
Compared to the rare Pentax 28/2.0 A, this 31/1.8 is inferior at full aperture, but better at f/2.8 and above.
Junior Member

Registered: May, 2013
Posts: 37
Lens Review Date: May 1, 2017 I can recommend this lens: Yes | Price: $680.00 | Rating: 9 

Pros: sharpness, build
Cons: price
Sharpness: 10    Aberrations: 10    Bokeh: 10    Autofocus: 10    Handling: 10    Value: 8    New or Used: Used    Camera Used: Pentax K-S2   

Mine is a used Pentax FA 31 1.8: black edition, assembled in Vietnam. This copy may have been manufactured around 2012 or so, since Ricoh does not yet appear on the box although the paperwork already mentions the acquisition by Ricoh (which I understand happened in late 2011).

Autofocus is accurate with the K-S2, even when shooting at max aperture.

I’m pleased with the images taken with the Pentax K-S2. Properly focused (with the exception discussed below), images are acceptably sharp from corner to corner even at f/1.8. Compared to my A 28 2.0, K50 1.2, and DA 50 1.8, the FA 31 has noticeably better sharpness/contrast at large apertures. I would rate the FA 31 in the same league as the Zeiss 2/35 in sharpness.

Now the exception. With the focus at infinity, closer in-focus subjects are significantly sharper than subjects farther away below f/8. Focused at infinity, closer subjects, such as objects across the street, are acceptably sharp from corner to corner even at f/1.8, while subjects farther away — even those near the center of the frame — are blurry. More distant subjects sharpen up at f/8.

Example below shows what I mean.

The test scene shows objects across the street (electric posts), and farther away a construction site.

These are 100% crops, unsharpened, no adjustments.

So it’s f/8 for landscapes, any other aperture for closer subjects. My Zeiss 2/35 behaves like the FA 31 for distant subjects, so that does not seem like a peculiar behavior.

Below is a handheld shot using the FA 31 at f/8, no sharpening.

This is a 100% crop of the rocks.
Site Supporter

Registered: December, 2013
Location: Houston, TX
Posts: 1,717

10 users found this helpful
Lens Review Date: April 22, 2017 I can recommend this lens: Yes | Price: $1,000.00 | Rating: N/A 

Pros: Absolutely Stellar on APS-C
Cons: Middling on FF, high price, built-in hood
New or Used: New    Camera Used: K-5 IIs and K-1   

I've avoided giving numerical scores in the above listings because the number depends entirely on whether you use this lens with an APS-C or the full frame K-1. It's a very different story with the two sensor sizes.

My usage heavily colors the direction my review takes. I shoot people almost exclusively with a little bit of travel sites when I do that. I prize rendering and use a lot of focus points off center because I don't position my models in the middle. I push my equipment to the edge of its capabilities and expect a lot of it. I figure if you're considering a $1000 lens, you probably have high expectations too!

APS-C Sharpness: 10
Full Frame Sharpness: 7
On APS-C, this is probably the best lens you could use. It's sharp and it has a very distinct means of rendering textures that give it a characteristic look. It has superlative 3D pop: it's sharp in the focal plane and smooth and smarmy outside with a quick drop. It's gorgeous, in a word. There was a reason why this lens rarely came off my K-5IIs. Contrast is strong.

On Full Frame, it's a different story. This lens doesn't pack a lot of resolution and it renders things kinda...dull. The contrast is much weaker and it just looks...kinda meh. It's not terrible and some post-processing sharpening helps but this lens is sadly not up to snuff for the K-1. I look forward to the modern replacement on the roadmap.

APS-C Aberrations: 8.5
Full Frame Aberrations: 6
In high contrast situations, this lens has a propensity to purple fringing, although it's not nearly as bad as the FA77, which I would describe as "fringing like crazy." It's usually easy correctable in post processing, however. Green-bokeh fringing is quite pronounced, more than any lens I've ever seen, and not fixable. If you're a purist, it's an issue, but I'd say it's part of the lens's character. I wouldn't call it unpleasing but it's very noticeable if you look for such things.

On an APS-C camera, barrel distortion is well controlled and the lens is sharp from corner-to-corner. On a full-frame camera, this is not the case and the lens displays significant distortion toward the edge of the frame. In particular, faces tend to be warped badly and geometries distorted. The center is great, however, which is why this lens excels on an APS-C camera.

It should be noted that wide open, this lens is not so good. You really need to stop down to f/2.5 or so to see it shine. f/2.8 is spectacular, at least as APS-C goes.

APS-C Bokeh: 9
Full Frame Bokeh: 7
I've knocked the APS-C bokeh down to a 9 because of the ubiquity of green fringing. Otherwise, it's smooth, clear, and really really pleasing. I found myself in awe of what this lens could do on my APS-C. Maybe I was just inexperienced but it's just amazing.

On the K-1,'s more complicated. Because you need to be closer to get the same framing as you would on APS-C, you run into issues with perspective distortion with certain subjects, such as humans. As a result, you need to move farther back...but the short focal length means you lose a lot of your background blur in the process. I've rated this a 7 because while the quality is the same, it's much harder to obtain it: you don't want to be close to your subject so you are forced to back up and open up the lens. Then the focus accuracy decreases's just not so fun. Maybe I'm just too used to using it as I did with APS-C and disappointed that I cannot.

Never had a problem with my first copy on APS-C. I damaged the lens after getting my K-1 and had a host of issues. I had it repaired and found the focus erratic. I replaced the lens with a new copy and sent that one back because it's focus was erratic. The new one hasn't arrived yet. I'm worried this lens itself and the K-1 just don't get along well. I've found it really has issues with the K-1 in difficult contrast situations. In particular, if you're using the outer focus points with the's a crapshoot. This makes sense: the focus points on the K-1 are much farther from the center of the frame than the outer focus points on an APS-C body. As I've described the distortion and contrast issues as the larger image circle is used, this explains the focus issues.

Remember that this lens was designed for a film body like the MZ-S, which had a state of the art 6 focus points, all of which are in the center. The lens really struggles with off-center focus points on a full-frame camera in a way it did not with an APS-C body.

Handling: 8
The lens is small and compact, although it's larger than other APS-C lenses you might acquire. It's modest for a full frame lens. I knocked this down some points because the built-in hood is irritating. It's completely insufficient on APS-C to the point of uselessness; it impedes the use of another hood simply because it gets in the way. Fortunately, a metal screw-in hood meant for a Panasonic camera can be had for a few dollars and it works perfectly (search the forums for it) but this hood vignettes on full frame badly. On FF, you're stuck with the built-in one because you can't add anything that protrudes from the sides, so a short rubber hood won't work. Another major downside is that only the Hoya variable ND filter will fit in side and that filter doesn't have threads on the outside, so you have to remove the add-on hood if you're using it on APS-C.

Aside from the hood issues, though, the lens is great in its ergonomics. It's small and well-balanced on every camera.

APS-C Value: 8
Full Frame Value: 5
This lens is pricey and that doesn't depend on the body. But what you get on an APS-C body is a premium normal-FoV lens and on full frame, you have a very overpriced middle-class wide-angle lens. I haven't used the FA35 but I suspect the FA31 isn't light years better than it on FF, at least not worth 3-4x the price. And that's what hurts this lens's value: it's an ok lens but it's not $1000 good on full frame. It is on on APS-C, where it is the alpha, the omega, and everything else between for crop bodies.

While full-frame compatible, I can't really recommend the lens for the K-1 simply because of it's price. It's a modest performer and the truth is we're stuck with it: there's nothing else available in this focal length except the FA35. There are other options for APS-C (like the DA35 Macro) but the FA31 beats them hands down. It should be your go-to lens on APS-C and one you use occasionally on the K-1. I've personally come to prefer the FA*24, which is not as sharp, of course, but has more interesting rendering that makes up for it.

What else? Oh, color. It's quite nice and if this is all you know, you'd be quite pleased with it. However, it's definitely not as accurate or punchy as either the FA77 or DA*55, both of which boast superlative color saturation. This lens seems to do best in bright sunlight with landscapes; I find it a bit ruddy inside or without 50-60% flash to ambient ratio.
Site Supporter

Registered: October, 2008
Location: Vancouver, Canada
Posts: 6,202

2 users found this helpful
Lens Review Date: March 5, 2017 I can recommend this lens: Yes | Price: $1,250.00 | Rating: 9 

Pros: Sharp, fast and great handling.
Cons: A bit overrated, cheaper lenses are just as good optically.
New or Used: New    Camera Used: Pentax film bodies (K1000, KM, KX, K2, K2DMD, ME, MX, LX, Super A/Program, P50)   

The FA31/1.8 was released in 2001 and is still in production today. Pentax produced a similar focal length K30/2.8 from 1975 to 1984, so you could consider the FA31/1.8 a refresh of that older manual focus lens. The FA31/1.8 is also the third and last of the FA Limited’s lenses to be released.

Excellent, which should be no surprise considering the cost of the FA31/1.8 and the optical “extras” added to the lens. (Aspherical element, high-reflection low dispersion element, anomalous dispersion element & a floating lens system)

Focal Length:
I find the 30-31mm focal length on FF is not quite wide enough when I’m choosing a single wide-angle for a three prime lens travelling kit and usually go for something wider, like a 20-28mm lens. I find the 30-31mm focal lengths work better as a second wide in a larger kit along with a 20mm lens or as a one lens option on a day trip.

On an APS-C camera you have the perfect “normal/standard” focal length, so I can see why the FA31/1.8 has been so popular on digital over the last decade.

The build of the FA31/1.8 is good for a FA Series lens, but is not as solidly built as any Takumar/K/M Series lens I own.

The FA31/1.8 is a nicely sized well balanced lens that is easy to handle and the best out of the three FA Limited’s. I have no issues manually focusing the FA31/1.8 or using the aperture ring. The distance scale is the “compressed” style, but you get used to it. Overall not bad for an Auto Focus lens.

The FA31/1.8 has a built-in “tulip style” lens hood and accepts 58mm filters, which screw-on inside the ridged hood. The lens cap is a push/slip-on like the rest of the FA Limited’s and is also prone to falling off. I’ll substitute it with an older Takumar 58mm lens cap when I’m travelling, so the OEM cap doesn’t get lost. The FA31/1.8 originally came with a red soft lens case marked “PENTAX 31/1:1.8”, which was later replaced with a black one.

F1.8 is very fast for a wide-angle lens and it makes the FA31/1.8 the fastest wide angle lens ever made by Pentax. (Excluding the prototype M35/1.4)

The FA31/1.8 vs my favourite 28-30mm wide primes:
I also own the K30/2.8 and several 28mm lenses, my favourite being the K28/2. All three lenses have excellent middle aperture sharpness and I don’t really see any difference between the three. The K28/2 is the best wide open and the FA31/1.8 the worst, though I’m unlikely to ever use any of these three lenses wide open. (Note it’s hard to evaluate/compare these three lenses wide open as each lens has a different maximum aperture & focal length.)

Build/handling wise the two “K” Series lenses are better and the K28/2 has the best minimum focusing distance. The FA31 wins the speed race, but is the least wide of the three.

The K28/2 however has a “3D” effect that I just don’t get with the other two lenses, so that’s by far my favourite wide angle lens overall. There is something about the legendary Pentax/Carl Zeiss designed K28/2 that is magical, the FA31/1.8 & K30/2.8 are excellent but not in the same league.

I rated the K28/2 a perfect 10 and the K30/2.8 a 9.5, the FA31/1.8 also gets a 9.5.

The FA31/1.8 is an excellent wide angle lens, however there are much cheaper manual focus options that are just as good or better overall.

I bought my FA31/1.8 from an online camera store and paid $1199.00 Euros. It was in LN condition, boxed with all the original paper work. It’s a silver low serial number MIJ, with a red soft pouch.

Sample shots taken with the FA31/1.8. Photos are medium resolution scans from original negatives. Both shots were taken in Vancouver.

Camera: P50 Film: Kodak Portra 400 ISO: 400

Camera: Super A Film: Kono Kolorit 125T ISO: 100
***Note this is old expired Kodak Tungsten movie stock film, so yes it's grainy***

Senior Member

Registered: April, 2015
Location: Boston,MA
Posts: 257

6 users found this helpful
Lens Review Date: November 30, 2016 I can recommend this lens: Yes | Price: $720.00 | Rating: 10 

Pros: IQ,rendering, bokeh
Cons: size, a bit soft at 1.8, price
Sharpness: 9    Aberrations: 9    Bokeh: 10    Autofocus: 9    Handling: 10    Value: 8    New or Used: Used    Camera Used: K1   

First of all, I like the focal length a lot, 28mm is a bit wide and 35mm sometimes is not wide enough for me. 31mm is perfect on the FF for me.

Not razor sharp below f2, but still pretty good, perfect for portrait. Once you step down to 2.8 the sharpness jumps to a different level.

Rendering of this lens is just special,not as contrasty as the ZK 35 but the overall feeling is slightly better than the ZK .Another great thing about this lens is that it's sharp at all distant,so you can use it for landscape, street shooting and portrait, not like my M28mm f2 , which is great at close distant but not so good at infinity.

Last but not least, the bokeh. IMHO the 31mm produces the best bokeh I've seen from a wide angle lens, the transition from in focus area to OOF area is so smooth.

Cons:it's not cheap and I wish it can be a little smaller just like the 43&77, it would be great to add WR in the future.
Overall, this is probably my favorite Pentax lens.

Site Supporter

Registered: April, 2015
Location: Wisconsin, USA
Posts: 2,151

2 users found this helpful
Lens Review Date: April 13, 2016 I can recommend this lens: Yes | Price: $475.00 | Rating: 10 

Pros: Great color and bokeh, built like a tank
Cons: Not super sharp wide open
Sharpness: 9    Aberrations: 9    Bokeh: 10    Autofocus: 10    Handling: 10    Value: 10    New or Used: Used    Camera Used: K3ii   

I recently purchased a used 31mm lens. Boy was it beat up, it was really "ugly". I've shot it extensively for about one month now and found that it works like a new lens, and it still makes wonderful images. Auto-focus is dead on although of course not the fastest. This lens is built like a tank, and will just keep on working - period! Now that's quality!

The colors it produces are exceptional as is the bokeh.

Could be better at f/1.8 and f/2, but hey, no lens is perfect - though this one is very close.

I spent a day comparing this lens to my Zeiss ZK 35mm f/2 lens. Overall, I just liked the IQ of this Pentax 31mm lens a bit better, so I've put my Zeiss 35mm lens up for sale.

I also compared this lens to my Sigma Art 18 - 35mm f/1.8 lens. At 31mm, the Sigma is a bit sharper at all apertures than is the Pentax 31mm lens. Also, at f/1.8 and f/2, the Sigma Art images are overall better than the Pentax 31mm. However, the Pentax 31mm lens has this terrific rendering that's just hard to describe. So, I'm keeping both lenses. Will use the Sigma where precision is needed, and will use the Pentax where I am going for an "artistic" rendering.
Senior Member

Registered: May, 2011
Location: Hanoi
Posts: 199

2 users found this helpful
Lens Review Date: August 27, 2015 I can recommend this lens: Yes | Price: $900.00 | Rating: N/A 

Pros: metal build, silver edition
Cons: nil
Sharpness: 10    Aberrations: 10    Bokeh: 10    Autofocus: 9    Handling: 10    Value: 10    New or Used: Used    Camera Used: Pentax K3   

The legend!

TIMES yoga, on Flickr

TIMES yoga, on Flickr

TIMES yoga, on Flickr
New Member

Registered: May, 2015
Location: Setúbal (near Lisbon)
Posts: 5

2 users found this helpful
Lens Review Date: August 23, 2015 I can recommend this lens: Yes | Price: $796.00 | Rating: 10 

Pros: all
Cons: none
Sharpness: 10    Aberrations: 10    Bokeh: 9    Autofocus: 9    Handling: 10    Value: 9    New or Used: New    Camera Used: Pentax K20D   

My best lens and maybe one of the best lenses ever made. Pentax should make a full frame camera for this lens.

Add Review of SMC Pentax-FA 31mm F1.8 AL Limited Buy the SMC Pentax-FA 31mm F1.8 AL Limited

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