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SMC Pentax 50mm F1.2 Review RSS Feed

SMC Pentax 50mm F1.2

Reviews Views Date of last review
57 281,577 Thu June 30, 2022
Recommended By Average Price Average User Rating
98% of reviewers $339.40 9.32
SMC Pentax 50mm F1.2

SMC Pentax 50mm F1.2
SMC Pentax 50mm F1.2

The SMC Pentax 50mm F1.2 is the original version of Pentax's fastest SLR lens. It was later replaced by an A counterpart. A special gold-plated version was briefly made together with the Gold LX.

SMC Pentax 50mm F1.2
©, sharable with attribution
Image Format
Full-frame / 35mm film
Lens Mount
Pentax K
Aperture Ring
Yes (no A setting)
Automatic, 8 blades
7 elements, 6 groups
Mount Variant
Check camera compatibility
Max. Aperture
Min. Aperture
Min. Focus
45 cm
Max. Magnification
Filter Size
52 mm
Internal Focus
Field of View (Diag. / Horiz.)

APS-C: 32 ° / 27 °
Full frame: 47 ° / 40 °
Various types will fit
Hard case HB-90
Lens Cap
Plastic clip-on
Weather Sealing
Other Features
Diam x Length
65 x 48.5 mm
385 g
Production Years
1975 to 1984
Engraved Name
SMC PENTAX 1:1.2/50 (early version), smc PENTAX 1:1.2 50mm (later version)
Product Code
User reviews
Sold without hood. Several hoods will fit such as PH-S52 (50mm) and PH-R52.
Manual FocusAperture RingFull-Frame SupportDiscontinued
Price History:

Add Review of SMC Pentax 50mm F1.2
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Site Supporter

Registered: June, 2008
Location: NJ
Posts: 1,824
Review Date: June 30, 2022 Recommended | Price: $350.00 | Rating: 10 

Pros: Excellent Build. Absolutely creamy bouquet
Cons: None that I can tell. Autofocus Version will be fantastic
Sharpness: 10    Aberrations: 10    Bokeh: 10    Handling: 10    Value: 8    Camera Used: K5   

After looking for this lens for so many years, I found it. I used it to take pictures of my kids. Now they outgrow the picture posing stage. My eye sight is not what it used to be and now it is harder for me to use manual lenses. That is why I use it with my Pentax-F 1.7 Adapter to create a version of the Pentax 85mm 2.0 with excellent results. It is fast and the bouquet is the best out there.

I can't say anything bad about this lens. The build is superb. It is build like a tank. Protecting the front element it is worth to spend $ for a nice 52 mm UV filter.
It took me some time to get used to the sharp shallow Depth at F 1.2.
Overall, the best lens I owned.
Senior Member

Registered: June, 2013
Location: Utrecht
Posts: 175

5 users found this helpful
Review Date: September 4, 2020 Recommended | Price: $300.00 | Rating: 10 

Pros: K-build quality, bright, sharp, contrasty
Cons: Rare, rather expensive
Sharpness: 10    Aberrations: 9    Bokeh: 10    Handling: 10    Value: 10    Camera Used: K1ii   

Besides the K35 F2.0 this one also got on my way. My very first camera was the black Pentax K2 with the K55 F1.8, I still have that camera and now in 2020 the lens that was made for it is in my cabinet too. This lens feels like a hand grenade, coupled on a K1 this is a 1.5 kg combo. My copy is quite mint with clear and clean glass in it and everything works as intended.

This is a good lens for what it is, it shines in low contrast evening shots. Always use the hood, also in the dark. Be aware you must underexposure in that kind of situations, the standard metering wants to overexpose to daylight but that is not what you want. It is also better to shoot in RAW, wide open the RGB-diagram must be adjusted manually at 16 bits to collect all the sensor has caught without having bandings.

Focusing wide open must be done in live view and the 8x magnify function, this is very accurate. Using just the viewfinder, "in-focus" beeps and focus-peaking are not adequate enough, the DOF is extremely narrow nearby. Wide open nearby objects are rendered nice and sharp, at infinity wide open shots are quit soft and hazy. This lens is made for object isolation nearby, so this is OK.

I compared the K50 with my M50 F1.4 and K55 F1.8. Besides weight, a half stop difference, an even more narrow DOF and smoother bokeh wide open there is very little in between the 1.2 and 1.4. At F2.0 and further on the differences are negligible, both lenses perform superb and shine with contrasty and super sharp images between F2.8 and F8. The K1.8 stays a little behind those two, over the whole range not as crispy. The DFA 28-105 comes in at F4.5 and also is not as crispy as the two primes. I also like the color rendering of the two bright primes better, more vivid.

In case you own a F1.4 this F1.2 adds little functionality. But it is so nice build, feels so sturdy, and looks so great on your camera that am very happy owning and using it now. It is the best and most versatile 50mm I own. Here are some recent shots, all wide open:

K 1.2 shot wide open, flower in the center was my focus point:

M 1.4 shot wide open, same flower in focus:


Registered: January, 2017
Posts: 434

1 user found this helpful
Review Date: February 6, 2020 Recommended | Price: $230.00 | Rating: 10 

Pros: bokeh, sharpness, colours, build
Cons: none
Sharpness: 10    Aberrations: 9    Bokeh: 10    Handling: 9    Value: 10    Camera Used: Pentax K-1   

Regarding built quality which is great, I wish the aperture ring was like in M series lenses, i.e. bigger, easier to hold and rotate. Otherwise no issues regarding built quality. Bokeh is really smooth and colours are great. Great portrait lens. Almost no need for adjustment of colour output of this lens. Very powerful colours. It really shines in darkness at f1.2. No issues with focusing this lens with focus peaking at f1.2. At normal portrait distance it works great without any aberrations at f1.2. You may run into problems with them if you try to use this lens as a macro lens at minimum focusing distance. Then it's not easy to focus because dof is so shallow. They don't make lenses of this quality any more.


Registered: November, 2018
Posts: 465
Review Date: October 3, 2019 Recommended | Rating: N/A 


New Member

Registered: August, 2019
Posts: 2
Review Date: October 1, 2019 Recommended | Price: $380.00 | Rating: 10 

Pros: Takumar build quality. Superb handling. Fast aperture.
Cons: A bit soft at F1.2
Sharpness: 10    Aberrations: 9    Bokeh: 10    Handling: 10    Value: 9    Camera Used: Sony a7iii   

Super creamy bokek at F1.2. Excellent lens.

50mm at F1.2
Senior Member

Registered: December, 2012
Posts: 166

1 user found this helpful
Review Date: December 20, 2018 Recommended | Price: $250.00 | Rating: 9 

Pros: Good image quality
Cons: Sometimes weird bokeh
Sharpness: 9    Aberrations: 8    Bokeh: 9    Handling: 10    Value: 10    Camera Used: K-5   

I never really got hooked on it until I shot raw.
Let the pictures speak.

Junior Member

Registered: March, 2014
Posts: 27

1 user found this helpful
Review Date: December 17, 2018 Recommended | Rating: 7 

Sharpness: 8    Aberrations: 8    Bokeh: 8    Handling: 10    Value: 5   

Was searching for an affordable copy for years and finally managed to get a combination of a K2 body, the smc 50mm f1.2 and a K 200mm f4 for just 135 euro. All in great condition. I kept the K2 and the K 200mm f4 but was not impressed by the 50mm f1.2.

What I like about the lens is the build quality, the relatively small size and the contrast wide open. For a f1.2 it has very good contrast, probably thanks to the SMC coatings. What I don't care for is the sharpness wide open, the amount of CA and the quality of bokeh. For sure the backgrounds are very much blurred and smooth looking, however I personally find the bokeh to be a bit boring. It does have the thinnest depth of field from all 50mm Pentax lenses, so if you really are longing for that it will do the job. But for some reason I like the bokeh of my smc 55mm f1.8 more. I think the transitions from sharp to out of focus areas are more pleasing with that lens, it feels more natural and gives a better 3D effect. Also the sharpness wide open is just better. There's plenty of bokeh to play with even using a f1.8 lens, and I would certainly not regard the f1.2 to be 'in another leage'. In the seventies, the f1.2's where not especially develloped for their quality of bokeh but in order to get the highest possible shutter speed in low light conditions. Using digital sensors, the necessaty of such an aperture is gone.

It all comes down to personal preference, but I sold the 50mm f1.2 since it is so popular and one can get a good price for it. I am a collector of Pentax K lenses but I just didn't think I would be using it a lot. Imagine that for about the same price you can buy a K 28mm f3.5, K 55mm f1.8 and a K 135mm f2.5 all at the same time. And if you're lucky, even a K 200mm f4

A f1.2 lens with K mount that I do recommend is the Revuenon or Rikenon or Vivitar series 1 55mm f1.2, Tomioka made, 9 aperture blades, great sharpness wide open, very nice bokeh with lots of character. Bit lower contrast wide open then the Pentax 50mm f1.2 but that can be corrected in post.
New Member

Registered: September, 2017
Location: Norwich
Posts: 4

1 user found this helpful
Review Date: October 27, 2017 Recommended | Price: $30.00 | Rating: 10 

Pros: Bokeh, build quality, colour rendering, sharp
Cons: CA in f1.2
Sharpness: 10    Aberrations: 8    Bokeh: 10    Handling: 10    Value: 10    Camera Used: Panasonic Lumix GX80   

I was lucky enough to get this lens in a giveaway from a person that didn't know (and didn't want to learn) its value with a lot of other Pentax equipment. It is in a pristine condition, both in build and optics, not even a hint of dust, so I guess I've hit a jackpot.

Mine is a late version, and is supplied with a hood. I only changed the Photax UV filter that it had on, as it must have seen a lot of action, and replaced it with a Hoya Pro1 Revo UV(0).

Technically I don't have a lot to say. You get a fully manual lens, which works wonders in photos and shooting 4k videos as well. I could never ask for better bokeh than this. It feels artistic/dreamy and gives a whole new dimension in what you shoot. Additionally, the colour rendition is just amazing. Its weight can be a problem in some cases as the weight balance is not optimal in a m4/3 body which I use it in (Panasonic Lumix GX80/85). However, as a construction, it feels as solid as it gets. Also the focus ring is smooth and a joy to use. The aperture ring feels robust.

High contrast areas should be avoided from what I've seen so far, when A is set to f1.2. I can see CA but nothing that makes the result unusable. The sharpness is more than excellent in f1.4 and jawdropping from f2 onwards (I still cannot believe the details it gets).

Overall this is now my favourite lens, even for walking around, taking the crown from my Pentax-A 50mm f1.7. They're simply in entirely different leagues, and I absolutely LOVED the latter (and still do).

Forum Member

Registered: February, 2016
Location: Moab, Utah
Posts: 90

3 users found this helpful
Review Date: July 17, 2017 Recommended | Price: $575.00 | Rating: 10 

Pros: Bokeh, color rendering, shrpness in that order
Cons: heavy, big, rare
Sharpness: 10    Aberrations: 10    Bokeh: 10    Handling: 9    Value: 10   

Best dreamy bokeh from Pentax. I also have the K 50mm f1.4, Takumar SMC 50mm f1.4, M 50mm f2, A 50mm f2. Without a doubt, this one offers the best bokeh. This lens is all about the bokeh and speed. You pay for it and everything else suffers as a result. Fine, fine bokeh. A big difference even just from f1.4. Call it "twice the bokeh" if you will from 1.4 IMO. I see no difference between this and the SMC 50mm f1.4 as far as colors, contrast, overall image "look" when compared at f1.4. It's not razor sharp at f1.2, but then you can't really expect that. "Dreamy" from f1.2-f1.4, where sharpness begins creeping in. When you compare with the Super Tak or SMC Tak 50 1.4, you get further degrading of bokeh quality due to the 6 bladed aperture vs. 8 bladed that you get with K 50 1.4 or K 50 1.2. I've not tested the early variant Takumar 50 1.4 with 8 elements and 8 bladed aperture.
The 50mm f2 lenses don't compare. They're different lenses for different purposes. The 50mm f2 M and A offer slightly better fine contrast and punchier colors, and more 3d pop.

I gave this lens all 10's except for handling, which I gave an 8. It's big and heavy. Actually it's small for an f1.2 50mm, but the aperture ring can be hard to find by sense of feel due to the large diameter and ring not sticking up a bit. A little higher aperture ring would be nice. I could probably give it a 10 for handling since it's smaller than any other 50mm f1.2 lens out there that I know of for 35mm film or sensors.

This lens needs a lens hood. Not so much for contrast or flares (it actually resists quite well), rather to protect it. It's compact & heavy and so seems to want to go nose first into anything and everything it sees.

*For anyone curious and wanting to compare 50mm lenses from Pentax, I did a YouTube review video while comparing them for myself. You don't need to collect them all like I did, just check my video:
Junior Member

Registered: December, 2012
Location: Cirebon
Posts: 29

1 user found this helpful
Review Date: January 17, 2017 Not Recommended | Price: $400.00 | Rating: 4 

Pros: Build, Historical, Mechanical
Cons: FLARE, Comma, Ghosting and Little bit distortion for 50mm lens
Sharpness: 8    Aberrations: 6    Bokeh: 7    Handling: 8    Value: 5   

Terrible flare and ghosting. Just buy this if you are a collector.
New Member

Registered: January, 2017
Posts: 4

1 user found this helpful
Review Date: January 17, 2017 Recommended | Price: $350.00 | Rating: 10 

Pros: Build quality. Dreamy 1.2. Intimidation factor.
Cons: Tricky to hit focus right
Sharpness: 9    Aberrations: 9    Bokeh: 10    Handling: 10    Value: 9    Camera Used: ME Super   

It almost weighs as much as the ME Super it's mounted on. I love it.

Wide open, it confers a dreamy, swirly look to photos which I love. Closed down it's very sharp and renders colours wonderfully.

The heft and girth of the lens make it a pleasure to use, and I just love how it swamps my SLR.

Absolutely recommended. I had used the Pentax-M 50mm 1.4 previously and can confirm they're in different leagues.

Senior Member

Registered: April, 2015
Location: Lower Saxony
Posts: 181

4 users found this helpful
Review Date: November 21, 2016 Recommended | Price: $309.00 | Rating: 10 

Pros: creamy bokeh, sharp and contrasty wide open; tolerable vignetting wide open
Cons: starts more soft up to f/2.8 than SMC 1.4/50
Sharpness: 9    Bokeh: 10    Handling: 9    Value: 9    Camera Used: Pentax K-1   

Wide open and up to f/2.8 it seems to be a little bit more soft than the SMC 1.4/50.
But it is able to produce sharp and contrasty pictures with open f/1.2 apperture at less than 2m subject distances;
depending on light situation and motive.
Bokeh is creamy and you can create nearly impressionistic backgrounds.
Some not post processed jpgs for example;
click into to enlarge original out of camera jpgs.
ISO 100, camera 35mm DSLR Pentax K-1, all open f/1.2 aperture.

harsh noon light

warm afternoon light

hazy noon light

hazy but also harsh noon ligt
(nice f/1.2 spin off: ugly power poles - here are a lot - become nearly invisible - left frame border)

noon light, f/1.2 dof

Edit 2016 12 21:
the shortest days noon.
K-1; K 1:1.2/50; @f/1.2; linked to ooc jpg.

Veteran Member

Registered: November, 2013
Posts: 1,740
Review Date: May 28, 2016 Recommended | Price: $300.00 | Rating: 10 

Pros: Sharp wide open, high IQ, colours, bokeh
Cons: rare, expensive, heavy on some small Pentax cameras, some barrel distortion
Sharpness: 10    Aberrations: 8    Bokeh: 10    Handling: 10    Value: 8    Camera Used: LX, K2DMD   

The K 50mm f1.2 was the first 50/1.2 for SLR that hit the market in 1975, Pentax was able to beat Nikon and Canon in the race for this formula (Nikon introduced its 50/1.2 in 1978 and Canon in 1980) that was very sought after mostly for commercial reason (as explained in this interesting article: Very few people remember that Pentax was able to beat the top two names in the game and their 1975 rightfully boasts this achievement...according to Keppler in the Pentax way Pentax migrated from the S system to the K system mostly because they needed an enlarged mounting diameter for the rear element of their 1.2 that as a matter of fact is one of the most beautiful pieces of glass I've ever seen.

I don't have the Nikkor 50mm f1.2AI but I have a standard FDn 50mm 1.2 and a FD55mm 1.2, while the new Canon is a great lens I feel that in terms of sharpness and bokeh the Pentax is a better lens, the FD55m 1.2 is loaded with coma, flare and low contrast wide open and according to the already cited article even the Nikkor 55mm f1.2 wasn't that great, so the Pentax can be considered the first standard 1.2 (aspherical Canon 55m notwithstanding) that can be used wide open and not as sort of "effect lens" (for instance as soft focus).

I have the lens number 1200322, that makes it one of the earlier 1.2s made in 1975 (the one used in the official K mount brochure has a higher serial number). I paid 220 of it, besides few particles of dust is in great conditions, the building quality is top notch (even if Pentax didn't lacquer their lenses as Nikon and Canon did at the time) with a well damped focus ring and half clicks between f1.2 and f16 (single click then to f22). It's one of the few 1.2 that actually can close down to f22 and it proves it was meant to be a everyday's 50mm with more low light capabilities than the 1.4 and 55mm 1.8 siblings, so it's not a bokeh lens and I use as such for any kind of picture.

While it's small comparison to a Canonikon lens of the ear, the weight and diameter is substantial for a Pentax camera and it's large for a LX while feels at home on a Pentax K body, however looking through a LX or K2DMD viewfinder with this lens is like looking through a window in a sunny day.

In terms of IQ it's similar to the K50mm f1.4 and the Takumar antecessor, just on steroids. As written the lens works wel at f1.2 (if you are able to focus properly which is a challenge), the only optical drawback is a certain barrel distortion that I have seen in this test picture:

The following are pics taken at f1.2 on B&W (ilford XP2+) or colour (Gold 200 and Fujipro400) film with a LX/K2DMD, while I am not a pixel counter I think they show the optical qualities of this 40 years old lens:

At f11:

DOF at f22:

There is PP in the pictures, what you see if what you get from the lens, the camera and the film.

The only real drawback of this lens is that is probably one of the scarcest 50/1.2 on the market and the prices are high, besides that if you don't mind the slight distortion barrel perhaps this old lens can still compete against newer lenses.
Senior Member

Registered: June, 2012
Location: Brooklyn, NY
Posts: 230

1 user found this helpful
Review Date: January 10, 2016 Recommended | Price: $330.00 | Rating: 10 

Pros: Gorgeous bokeh, colors, contrast. SOLID.
Cons: Tough to focus, Learning Curve.
Sharpness: 10    Aberrations: 9    Bokeh: 10    Handling: 10    Value: 10    Camera Used: Pentax K3 II   

FANTASTIC lens. I have been thinking a lot about background lately as I recently purchased a DA 21mm 3.2 & DA 40mm 2.8 HD. I really like the size and sharpness of these lenses, but wanted to play around with subject isolation a bit. I did some quick searching around super wide lens and considered the Samyang and Sigma options - but after reading the reviews on this lens I was hooked. I found a good version (fingers crossed at the time) available on ebay with no bidders (which was odd.) I made a last second bid and got the lens for a few bucks more after someone tried to outbid me. It arrived a few days later and was in great condition.

Used the lens yesterday and WOW. It provides some gorgeous images, with amazing bokeh, and super sharp images. It took a bit of experimenting to figure out but I got some solid shots after only a few days of use. I actually started to like using the "Catch In Focus" on my K3 II as it provided some solid results. And yes the focus has to be spot on - but it can be done if you take your time. The Catch In focus also helped me as long as the exposure was short.

Anyway... take a look at some images I took and judge for yourself. I did use DXO OpticPro 10 to do some clean up. I considered not using it for this review, but most of the corrections were minor and I would use for any picture regardless of the lens.

I also totally understand why so many people post pics of flowers. The shots are so easy to capture and are wonderful.

New Member

Registered: August, 2015
Location: Stockholm
Posts: 15

1 user found this helpful
Review Date: November 2, 2015 Recommended | Price: $400.00 | Rating: 10 

Pros: Bokeh! sharpness at 1.2
Cons: Can't think of a thing..
Sharpness: 9    Aberrations: 8    Bokeh: 10    Handling: 10    Value: 10    Camera Used: Pentax K5 IIs   

Fantastic little lens!
Heavy but feels very balanced on my K5. Focusing is smooth but it's very crucial to get it right. When you do, you will fall in love with your pictures!
The bokeh is fantastic (!!) At 1.2 it is best used on close subjects, taking a picture at infinity gives you a quite soft image. Stepped down to 2.8 and beyond it is razor SHARP! As many other K era lenses it does have some CA, mostly in hight contrast areas where it usually shows. It's generally fixable in PP and have not been a problem for me since I like to shoot in B/W. It works well in Av mode but with slight underexposure. Manual mode and use of green button works best for me.

last but not least: It does require a good lens-hood when outdoors !

@ f1.2

@ f8
Add Review of SMC Pentax 50mm F1.2

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