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SMC Pentax-DA 40mm F2.8 XS Review RSS Feed

SMC Pentax-DA 40mm F2.8 XS

Reviews Views Date of last review
49 200,805 Mon September 18, 2023
Recommended By Average Price Average User Rating
94% of reviewers $155.59 9.04
SMC Pentax-DA 40mm F2.8 XS

SMC Pentax-DA 40mm F2.8 XS
SMC Pentax-DA 40mm F2.8 XS
SMC Pentax-DA 40mm F2.8 XS

The SMC Pentax DA 40mm XS is based on the optical design of the SMC Pentax DA 40mm Limited, but its exterior is designed by Marc Newson so as to match the design of the K-01 mirrorless camera. The lens will work with Pentax DSLRs as well as with the K-01.

It is smaller being only 9.2 mm thick. The aperture blades are rounded which produces a smooth bokeh. The front element has SP coating which repels dust, water and grease and which makes it easier to wipe the front element clean.

Price: $249 when purchased separately, $149 when purchased in a K-01 kit.

SMC Pentax-DA 40mm F2.8 XS
©, sharable with attribution
Image Format
Lens Mount
Pentax K
Aperture Ring
Automatic, 9 blades (rounded)
5 elements, 4 groups
Mount Variant
Check camera compatibility
Max. Aperture
Min. Aperture
AF (screwdrive)
Min. Focus
40 cm
Max. Magnification
Filter Size
27 mm
Internal Focus
Field of View (Diag. / Horiz.)

APS-C: 39 ° / 33 °
Lens Cap
Lens Front-cover 27
Weather Sealing
Other Features
Diam x Length
62.9 x 9.2 mm (2.5 x 0.36 in.)
52 g (1.8 oz.)
Production Years
2012 to 2023
$226 USD current price
$249 USD at launch
Engraved Name
smc PENTAX-DA 1:2.8 40mm XS
Product Code
User reviews
In-depth review
Unofficial Full-Frame Compatibility Tests by Pentax Forums
★★☆ Full coverage at some F-stop and focal length combinations
Show details

Screwdrive AutofocusAutomatic ApertureAPS-C Digital OnlyDiscontinued
Purchase: Buy the SMC Pentax-DA 40mm F2.8 XS
In-Depth Review: Read our SMC Pentax-DA 40mm F2.8 XS in-depth review!
Price History:

Add Review of SMC Pentax-DA 40mm F2.8 XS Buy the SMC Pentax-DA 40mm F2.8 XS
Sort Reviews by: Date | Author | Rating | Recommendation | Likes (Descending) Showing Reviews 1-15 of 49

Registered: April, 2015
Location: USA
Posts: 2,863
Review Date: September 18, 2023 Recommended | Price: $50.00 | Rating: 4 

Pros: Colors as good as any lens I own - more than acceptable sharpness
Cons: FRAGILE, poor manual focusing
Sharpness: 9    Aberrations: 8    Bokeh: 8    Autofocus: 9    Handling: 9    Value: 5    New or Used?: Used    Camera Used: Pentax K-01   

Superior color, excellent sharpness, good enough auto-focus speed and accuracy, tiny and light, and decent bokeh.

Negatives include: CA on high contrast borders, poor manual focus with too short of focus throw.

I owned this lens for only a few days. It was accidently droped and now it's a paper weight. VERY FRAGILE LENS! Not as well built and rugged as are most other Pentax lenses.
New Member

Registered: March, 2023
Posts: 1

1 user found this helpful
Review Date: March 9, 2023 Recommended | Price: $60.00 | Rating: 8 

Pros: Size, Overall IQ, Aparture Size
Cons: Easy to smudge lens, tiny cap, no hood
Sharpness: 7    Aberrations: 6    Bokeh: 8    Autofocus: 6    Handling: 10    Value: 8    New or Used?: Used    Camera Used: Pentax K10D   

Senior Member

Registered: October, 2022
Location: Glyfada, a southern suburb of Athens
Posts: 199

3 users found this helpful
Review Date: December 7, 2022 Recommended | Price: $113.00 | Rating: 8 

Pros: What lens? This is a camera cap with shooting abilities !
Cons: no pouch, no hood provided, flat/dull colors
Sharpness: 7    Aberrations: 7    Bokeh: 5    Autofocus: 8    Handling: 10    Value: 10    New or Used?: New    Camera Used: KP   

POP QUIZ: Where's the lens!?

We've actually bought the XS, a.k.a the biscuit, for the silver KP of Depy, my wife, and it's perfect in size to fit even inside a lady's bag; even in the pocket of a coat. Together with the KP it's like having a (fat) pocket camera. It's a solid 10! if you like doric minimalism or you're... an IKEA fan

[EDIT]: we finally decided I keep the XS as a constant "camera cap with shooting abilities" and my wife will get the sibling of XS, the much better HD 40/2.8 Limited in Silver that looks much better with her silver KP and the 7mm difference in height is truly negligible. On the other hand, my black KP will always have an extra lens in the bag and I will be using the back lens cover of the glasses I will be switching to protect the XS.

It was a kill deal. Purchased at 113 €/$ all inclusive, brand new, from a Japanese eBayer. Current street price in Greece at 299 €/$

The first thing that's upsetting though is that it comes without a pouch that is vital for the protection of this biscuit of fashion.

So you definitely need to buy a pouch; and we bought a pink leatherette pouch from Lidl at 4 euros. Not bad.

The second thing that's annoying is that Pentax does not provide a hood.

Sure, the hood would kill the "biscuit fashion" factor but for God's shake, Pentax did not apply HD coating and that means that the lens is exposed to flares and will most certainly provide images comparable to smartphones and not DSLR lenses. Why no HD coating when you know that your customers will be shooting without a hood???
Unbelievable !!!

So I purchased a metal hood that fits on it's miniscule 27mm filter ring. I also made a DIY hood cover using a cap purchased on a hardware store. I did warm it to make it fit better and I also put a touch of polishing cream for plastics inside so it won't scratch the hood

(attention: someone sells on the...bay chinese hoods as japanese)

The hood does improve mostly the quality of the photos because we have a problem without. The photos are DARKER ! without a hood and there is a big loss of contrast, For example:

I am kind of disappointed that Pentax played cheap on many aspects with its one and only "designer lens".

To be honest I mostly find the colors dull and boring with flat contrast (missing hood is partially guilty) when I compare this lens with the Limited. Nothing to admire. It just takes clean photos.

I've read the tests and I just don't feel that the colors or sharpness or basically the pentax quality is there. Something is seriously missing; sacrificed for the looks.

For me it's a lens for fun and definitely not for serious photography or magnificent results. Yet it's a compromise for its size and you know that you're buying a "lens in fashion" not a real lens for sweet photos.

It's a fashionable lens for point and shoot in AUTO. Nothing more, nothing less.

Judge by yourself. All photos shot without a hood.

First photo with the two toys is at f/2.8 ie maximum with ISO400.
Second with the plants at f/22 ie minimum with ISO4000.
Third photo with a flash again at f/2.8 with ISO4000 ( don't know why the ISO remained that high).

And since it becomes a custom to use our pets as our review models , below the portraits of Luther and Larry.

The black 20lbs "kitten" at ISO5000 and the cat at ISO1000; both at f/2.8 ie maximum lens aperture.

New Member

Registered: March, 2013
Location: NE England
Posts: 13

3 users found this helpful
Review Date: May 31, 2020 Recommended | Price: $150.00 | Rating: 10 

Pros: compact, build quality, sharpness, image quality
Cons: no aperture ring
Sharpness: 10    Aberrations: 9    Bokeh: 10    Autofocus: 9    Handling: 10    Value: 9    New or Used?: Used    Camera Used: K-01, KP, MZ-s, Z1-p   

When I first saw this lens I thought it was a toy or gimmick........

I couldn't have been more wrong! A superb lens. Some of the HDR and software IR images I have taken with my KP are superb!

I have the original M series pancake, which I rate highly but this lens is just superb for being A: auto focus and B: having rounded aperture blades.

I haven't tried the 40mm limited but I suspect that this lens will give you much more for your money and with a reduction in size!

Works with full frame film too! When I put this on my MZ-s it makes for a tiny combo!

Highly recommended!
New Member

Registered: August, 2018
Posts: 2

6 users found this helpful
Review Date: March 13, 2020 Recommended | Price: $200.00 | Rating: 10 

Pros: Super small, sharp and light
Cons: Due to small size harder to put on and off camera
Sharpness: 10    Aberrations: 9    Bokeh: 9    Autofocus: 8    Handling: 9    Value: 10    New or Used?: New    Camera Used: K-01   

I use this lens on my K-01 and find the focal length of 40 mm (61mm full frame equivalent) great for walking around the city as well as the parks. Some people prefer DA 21mm F3.2 limited or DA 35mm f2.4 for walk around lens but once one gets used to 40mm it has its advantages. I can put this camera (K-01) and the 40mm lens in the pocket of my winter jacket (the jacket needs to have big pockets) and that convenience alone makes me take this camera-lens combo out most of the time. The f 2.8 aperture is great in low light. For the wide angle shots I can take photos with my phone (which has an eq. of 18mm APS-c or 28mm full frame lens field of view). Combining K-01 with 40 mm f2.8 and the phone camera makes for convenient, easy to carry but somewhat unorthodox set up. Overall love this lens.
Veteran Member

Registered: January, 2019
Location: Geelong, Australia
Posts: 344

1 user found this helpful
Review Date: December 27, 2019 Recommended | Price: $105.00 | Rating: 8 

Pros: Tiny, makes street photography with a DSLR less conspicuous.
Cons: Lens cap.

I bought this in eBay at auction quote cheap and unexpected win with the low bid.
I was surprised that the lens is better than I thought it would be, however I do prefer a 50mm plastic fantastic with a similar focal length.
Senior Member

Registered: June, 2013
Location: Utrecht
Posts: 205

5 users found this helpful
Review Date: August 1, 2019 Recommended | Price: $100.00 | Rating: 9 

Pros: Extreme light and compact, fast focus, covers Full Frame
Cons: blue halos in harsh areas wide open
Sharpness: 9    Aberrations: 8    Bokeh: 8    Autofocus: 10    Handling: 10    Value: 10    New or Used?: New    Camera Used: K01 K1ii   

In 2013 I grabbed this new with a white K-01 for $ 350 from Amazon, my best deal ever. On the K-01 it works fine, for my needs it focuses well too with the latest software update. APS-C is covered completely, only little vignetting wide open. At F2.8 this lens shows a lot of sharpness, although around contrasty areas you will get deep blue halos. At F4 this completely disappears, from F4 - F11 this little lens is very sharp. Compared with other lenses the 40XS renders somewhat flat, you can pimp this up in post with the levels and contrast sliders. Focussing is fast and snappy.

Looking at the optical formula this XS40 is very similar with the FF pancake M40. So it is not surprising this XS40 is very useful on the K1 too. Wide open you get noticeable vignetting and the extreme corners (only) are unsharp. Stopped down a bit the vignetting almost disappears and 95% of the frame renders sharp. A XS40 on a K1 looks a bit odd but for street shooting it really is an ideal combo.

I never had any problems with the rubber cap, it works fine.

Full Frame Pictures: Fields at F 5.6, Castle wide open, extreme crop with blueish halos.

New Member

Registered: May, 2017
Location: Kiev
Posts: 12

5 users found this helpful
Review Date: November 23, 2018 Not Recommended | Price: $120.00 | Rating: 9 

Pros: Nice picture. Universal focal length, convenient for everyday use. Lightweight and small lens dimensions. Low cost in relation to image quality.
Cons: Inconvenient lens cap. There is no blend in the kit, which is necessary to improve the contrast of photos. Auto-focusing with this lens is not as simple as with others close in focal lengths (35mm., 50mm.).
Sharpness: 8    Aberrations: 7    Bokeh: 9    Autofocus: 6    Handling: 8    Value: 10    New or Used?: Used    Camera Used: K-5   

This is a very good lens! I like it more than 40 limited! Because KCC has rounded aperture blades. And the photos are more voluminous. And bokeh is more interesting and more beautiful.
I consider this lens as one of the best glasses for everyday use, in terms of price-quality photos! This lens is suitable for a leisurely, thoughtful shot. And although his autofocus works very quickly, the focus point often misses the target. Than napimer, 50mm lenses. Getting to the point of focusing with it becomes even more difficult if there is poor light. Or motley background behind the subject.
In addition, chromatic aberrations will appear on the open diaphragms in the photographs. If there is a strong contrast between the lighted and unlit areas in the picture. But this is not very pronounced. And the positive qualities of this lens are much more than unpleasant details.
For commercial use, I would not recommend 40XS, for the reasons described above. But for personal use this lens, I think a real find! It is so small and light that any camera with it will have the minimum dimensions and weight. And at the same time you will have a lens with a convenient focal length, for outdoor photography, for portraits, for genre and creative photography. In any situation where you have the opportunity to approach, or move away from the subject. If this is not possible, then it is better to purchase a zoom lens.
I definitely recommend this lens, because of its small size, low cost, good picture, beautiful color, pleasant bokeh!

The intensity of the bokeh and its drawing can be viewed in the attached photos below. Photographed with a f-number: 2.8; 4.0; 8.0

F 2,8

F 4,0

F 8,0

Below, in the photograph, a comparison of shots taken with different aperture values:

Below, in the photograph, a comparison of shots taken with different aperture values, with a 100% increase in the photograph:

Using these photos, you can understand the nature of the background blur, bokeh, depth of field at various apertures. I hope that someone my small review will help determine the choice of the lens.

P.S. I recommend this lens! But for some reason, the site itself puts "no" instead of "yes." I do not want. so that someone would think that I would not recommend this lens! Quite the contrary!
Junior Member

Registered: December, 2009
Location: Glenorie NSW
Posts: 45

3 users found this helpful
Review Date: June 25, 2018 Recommended | Price: $100.00 | Rating: 10 

Pros: light, small, excellent
Cons: lens cap
Sharpness: 9    Aberrations: 9    Bokeh: 9    Autofocus: 10    Handling: 10    Value: 10    New or Used?: New    Camera Used: K5, K3, K01, KP, K1-II   

I bought this lens as a kit with the K-01 for $AUD240 (about $US170). To quote Elwood Blues "They were practically giving them away". I figured a genuine Pentax battery and 40mm lens were worth it. The K-01 was a bonus. Due to an Amazon ordering anomaly I ended up with 3 bodies & batteries plus two lenses. I also have a Voigtlander Ultron f2 which is a manual focus lens. Generally the Voigtlander is superior if you ignore the manual focus however for street photography this lens is excellent. It is also a great travel lens and is easy to carry in a vest pocket on my KP. The biggest problem is the rubber lens cap though these can be sourced via ebay. All in all fantastic value for money.
Junior Member

Registered: May, 2018
Posts: 34

1 user found this helpful
Review Date: June 5, 2018 Recommended | Price: $190.00 | Rating: 9 

Pros: Technically great, light, looks stunning
Cons: Can't think of any
Sharpness: 9    Aberrations: 9    Bokeh: 9    Autofocus: 9    Handling: 9    Value: 9    New or Used?: New    Camera Used: Pentax K-1   

I love this lense. It is typical Pentax. They made this lense because they could and they're not sheep. Of course, there's no point making cool lenses if they don't deliver. I'll probably get a Pentax mirrorless body to go with this eventually but, for now, as someone who prefers to use prime lenses, having this one with you is hardly going to be the lense that breaks the Billingham bag's strap. If I have to use zooms ... because I might miss shots whilst changing lenses, I will but when I have the luxury of time, a bag full of primes is how I like to be kitted out. This lense is great FUN! I haven't seen many for sale. I think it's already regarded as a modern classic and people hang onto them
Senior Member

Registered: February, 2018
Location: Hérouville Saint Clair, Normandy, France
Posts: 143

2 users found this helpful
Review Date: February 26, 2018 Recommended | Price: $220.00 | Rating: 9 

Pros: Small, light, compact, sharp, fast
Cons: aperture, screw AF
Sharpness: 9    Aberrations: 10    Bokeh: 10    Autofocus: 8    Handling: 10    Value: 10    New or Used?: Used    Camera Used: KP   

Very light and fast lens, easy to operate. Perfect for portraits.
I used to shoot with the 35 2.4 and the 50 1.8 but now this one is my favourite.

Pentax KP - 1/40 - ISO 400
Seeker of Knowledge

Registered: August, 2016
Location: Topeka, Kansas
Posts: 24,559

1 user found this helpful
Review Date: December 27, 2017 Recommended | Rating: 9 

Pros: size and ability
Cons: supplied hood is press on and is easily falls off
Sharpness: 9    Aberrations: 9    Bokeh: 9    Autofocus: 9    Handling: 9    Value: 9    New or Used?: Used    Camera Used: K 3, K 3 II, KP, K 5 II. K-01   

08 03 20 - work around idea

some negative comments about this lens concern the press on cap which comes with this lens -

get a screw mount lens cap - hard to find

get a 27mm filter cheap as possible, glue original cap to it and you have your own screw mount lens cap


previous poster indicated that it was hard to find a hood,

I found this one

a little unusual looking but functional



I have had this guy for a while. I like it so much. I have found that under the right circumstances you can crop the image quite a lot and get some fantastic photos as a result.

cropped or uncropped it is a very nice lens
New Member

Registered: March, 2016
Posts: 2

1 user found this helpful
Review Date: July 18, 2017 Recommended | Price: $180.00 | Rating: 10 

Pros: Light, Small, Fast, Sharp, Colour, Contrast, Low Vignetting, Low Distorsion, T2.8
Cons: Cap?, Hard to find a hood
Sharpness: 9    Aberrations: 8    Bokeh: 10    Autofocus: 10    Handling: 9    Value: 10    New or Used?: Used    Camera Used: K3II K01   

I bought it about a year ago, but having so many lenses I had hardly tried it.

Last month I had the opportunity to buy a Limited 40mm and after doing many tests I decided to stay the XS, suffer less from flare, focus faster and more accurately. In Dxo the technical tests say that it is a T2.8, which means that it enters the same light that in the DA35mm F2.4, that in Dxo has T2.8 too.

The only problem was having to adjust the fine focus.

Color, sharpnes, contrast ... AMAZING LENS!
New Member

Registered: June, 2017
Posts: 2

3 users found this helpful
Review Date: June 3, 2017 Recommended | Price: $220.00 | Rating: 9 

Pros: Light l,sharp
Cons: Not particularly
Sharpness: 9    Aberrations: 9    Bokeh: 10    Autofocus: 9    Handling: 10    Value: 9    New or Used?: New    Camera Used: K3-2   

I love it!
I bought it with K - 01, but I think that K3 II is more effective.
It is thin, light, has little distortion, is the highest.

Exposure Time 1/400s (0.0025)
Aperture F/3.2
ISO 100

Exposure Time 3.000 s
Aperture F/3.5
ISO 200

Exposure Time 5.000 s
Aperture F/8.0
ISO 100
Exposure Time 1/1000s (0.0010)
Aperture F/3.2
ISO 100
Exposure Time 1/1000s (0.0010)
Aperture F/3.2
ISO 100
Veteran Member

Registered: July, 2014
Location: Nagoya
Posts: 577

2 users found this helpful
Review Date: July 31, 2016 Recommended | Price: $180.00 | Rating: 10 

Pros: Optical quality, size, convenience
Cons: None

This lens is a gem. So light and compact, it makes small cameras like the MZ-10 almost pocketable. The focal length is nice both on APS-C and film, and the lens works fine on all film cameras from the A series onwards. It's worth using on them, too, since the focusing ring, while small, is pleasantly damped and f2.8 is easily bright enough to focus using a split image. The focus throw is very short (presumably to help it focus on the K-01 for which it was designed) but this isn't a problem in practice for manual focusing, and means the AF is very snappy.

Image quality is fantastic right from f2.8 - sharp and clear with great colours and nice bokeh, which remains pleasant when stopped down, thanks to the rounded blades.
I really feel like I can't recommend this lens enough - it's an absolute steal at current prices, even here in the UK where gear tends to be a bit more expensive. If you see one, grab it.
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