DA and some elder lenses on Pentax K-1

As there is some speculation on which DA lenses that will work on the Pentax K-1 Full Frame, I will present some photos showing the extent of dark corners with some of the popular DA zoom lenses. As one can see, all DA zoom lenses have some degree of vignetting. Some will give dark corners all through, while some, like the 12-24 and 16-45 will be less affected towards the long end. In fact, the 12-24 is fairly good already at 17 to 18 mm. 
By zooming in one step (1,4 on the K-1) the dark corners are gone on all images presented. One can, of course, choose the auto-crop function on the camera, but that gives a smaller image than necessary. I would recommend to shoot at FF and resize on your machine. That is if you are able to evaluate what to cut while looking through the finder. If you always want to be on the safe side, then turn on the crop mode.

I have added some primes and zoom lenses from the film era, some dating back to the first K-bayonet lenses from the mid-70s. I am also testing M 42 Takumars from 1957 and on. The test photos may be presented on the Takumar pages.

For more about the variety of lenses for K-1: see Pentax K-1 FF: 2016-

Please note that these comments are for those not using D FA lenses. So far, I have tested the D FA 100/2,8 Macro, the D FA 28-105 3,5/5,6 and the D FA 150-450/4,5-5,6. They are all high-quality lenses with fast AF, beautiful colours, and very good to extremely good sharpness! AND WR.


K-1 + DA 12-24/4:

An 18-24 wide angel on full frame. Tested at 20mm against the FA 20/2,8 and the DA 16-45/4. It looses against both in sharpness, but not by much. All photos 800 ASA, F8.

Recommended with restrictions!

At 12 mm 800 ASA, F 8
At 17 mm ASA 800, F8
At 18 mm ASA 800, F8
At 20 mm ASA 800, F8
At 24 mm ASA 800, F8

K-1 + DA 16-45/4:

This lens needs cropping from 16 to 22 mm. So, it is recommended as a 22-40  wide angel on K-1 FF.(Hunting AF is reported at 16 and 45). As it extends towards 16 and compresses towards 45, there are problems with shadows on built-in flash images, which make it less suitable on K-3 and elder built-in-flash-cameras on wide angles. But on full frame I find it very useful as a 22-40 lens. Contrast and colour rendition is better than on FA 20. What speaks against it is the build quality, if that matters when you get a good shot.

Tested for sharpness on 20mm against FA 20/2,8 and DA 12-24/4. Very sharp, especially at 5,6, and keeps good results even in corners.  All photos ASA 800, F8.

Recommended with some restrictions!

At 16 mm ASA 800, F8
At 20 mm ASA 800, F8
At 28 mm ASA 800, F8
At 35 mm ASA 800, F8
At 45 mm ASA 800, F8

K-1 + DA 17-70/4:

Usable when cropped, but not recommended on FF compared to the 16-45. Functions as a 26-105 zoom when cropped, which is a good range. However, it is known for a hunting SDM AF. Mine is useless on AF at 70mm. All photos ASA 800, F8.

Not recommended.


At 17 mm ASA 800, F8
At 24 mm ASA 800, F8
At 35 mm ASA 800, F8
At 70 mm ASA 800, F8

K-1 + DA 18-135/3,5-5,6:

Good on aps-c, usable on FF, but not the one I would pick first, as it needs more cropping than any of the other DA lenses presented here. ASA 800, F8.

Not recommended.

At 18 mm
At 35 mm
At 70 mm
At 100 mm
At 135 mm

K-1 + DA* 50-135/2,8:

A very sharp lens, though soft wide open. Better at 4, and shines from 5,6. Needs cropping all the way. 

AF: SDM system on this lens is known to be a problem on items produced before 2012, as it is very slow or even nonworking. I had given it up, as it seemed dead. BUT: With the K-1, it started to work again! It sometimes needs to be kickstarted, but once alive, it works like a dream! 

ASA 800, F8.

Not recommended as a full frame lens, but once cropped it shows class.


At 50 mm.
At 70 mm.
At 100 mm
At 135 mm

K-1 + FA 20 2,8:

To compare, here is a prime 20 mm from the early '90s. Not the best sharpness wide open, but improves step by step. Excellent for keeping sharpness from foreground to background. Mine sometimes comes out a bit light compared to other lenses, making it seem to lack some contrast, at least wide open. Much better from 5,6. 
ASA 800, F8.


Some vignetting wide open. Better from f 4, but it can be seen even here. ASA 800, F 8.

K-1 + FA 28-70/4:

Here is another FA lens, produced from 1991. Sharp from f 6,3, but not as good as the FA 28-105/3,2-4,5. It even loses against the F 28-80, though not by much. Some vignetting at larger apertures at 28 and 35.

ASA 800, F11. 

Not recommended against FA 28-105.

At 28 mm.
At 35 mm
At 50 mm
At 70 mm

K-1 + F 28-80/3,5-4,5:

A not so highly valued F-lens from 1987: the F 28-80 macro zoom. But tested against the FA 28-70/4 and the FA 28-105/3,2-4,5, it comes out with a bit higher center sharpness than both at 35 and 50mm. On the long and short end, it needs 6,3 or 8. Loses sharpness towards corners. No visible vignetting.

ASA 800, F11.

Not recommended against FA 28-105.


K-1 + FA 28-105 3,2/4,5 IF/AL

A newer FA zoom introduced in 2001. Praised for its colour rendition. Sharpness is average to good, while a hunting AF (on some samples) made the total score rather moderate on Pentax Forum. However, we are talking K-1 here, and AF is fast and accurate, although more noisy than D FA lenses. I used it on a trip to Verona and Venezia together with the 31/1,8 and the Macro DFA 100, and it performed so well that I could hardly tell the difference from the other two when it came to colour and mood (and sharpness wasn't essential.)
The 3,2-4,5 works like this: 3,2 from 28-30, 3,5 from 30-40, 4 from 40-80 and 4,5 from 80 and up.
As a walkaround lens for the K-1, it outperforms the FA 28-70 and the F 28-80 from 50mm+ and has better corner sharpness all over. And no dark corners. A very plastic feeling, but it sometimes helps me getting what I want.

ASA 800, F8.

Recommended against other FA zooms in the area.

However, I repeat: these comments are for those not owning the D FA lenses. Compared to the D FA 28-105 3,5/5,6, this FA lens very clearly looses in sharpness from center to corners. Once one compares, this is highly noticeable.


At 28
At 35
At 50
At 70
At 105

K-1 + K 24/2,8:

Produced from 1977 till 1984. Known to be good at shorter distances, but a bit soft on eternity. This seems to be verified here. Plus too little contrast. DA 16-45 would be a better choice at 24mm.
It has a super build quality and good colour rendition, though.

ASA 800, F11.

Not a first priority lens.

K-1 + A 50/1,4:

A highly praised normal lens from 1984. But it needs 2 or 2,8 to shine, and keeps improving at least to 8,0. Manual focus.

ASA 800, F11. 

Recommended from 2,8.

K-1 + M 200/4:

A very sharp lens from 1976. Good colour tones and contrast. All manual. Tested for sharpness against F 100-300/3,5-4,5, F 70-210/4-5,6, FA 28-200/3,8-5,6, DA 18-250/3,5-6,3 and DFA 150-450/4,5-5,6, all at 200mm. Beats all except the latter, but comes out about even with the DFA from 5,6! 

ASA 800, F8.


K-1 + FA*300/4,5:

This lens has impressed me since I got it back in the 90s. Easy to use, good AF, though a bit noisy. Very sharp. 

ASA 800, F8.


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Antall tegn tilbake: 160
OK Sender...

Bosse | Svar 09.11.2020 22:32

Thank you!

Norfoot | Svar 05.11.2020 10:46

Very super nice. Thank you. From Norfoot / Roald Rafoshei-Klev

Wim HH van Heugten | Svar 19.10.2018 14:03

Hi Eric,
I don't understand your phrase: "Recommended as a 22-60 wide angel on K-1, and as 16-45 on K-3 II." The focal length range remains the same.

Bosse 19.10.2018 14:13

You are quite right. The vignetting disappears at 22, so it is usable from there on, but the maximum never exceeds 45. Thank you!
I will correct it. Bosse

Bosse | Svar 18.08.2016 14:08

Hi Eric!
No, I do not have all Pentax/Takumar lenses. But I have given some examples.
DA 16-50 will give dark corners. Close to the 16-45, perhaps?

Eric | Svar 18.08.2016 06:45

and the Pentax smc FA 50mm 1.4 !

Eric | Svar 18.08.2016 06:44


Any sample with a DA* 16-50? :)


Bosse 14.01.2019 20:55

Hi again,
The answer to your question about the DA 16-50 on K-1 came with the recent test on Pentax Forum: Not usable on any f-stop or focal length!

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29.09 | 19:44

Sorry, I misread your question, and my answer was about the Pentax K. The number of Pentar K was very, very low. Yes, 269$ seems a very low price.

29.09 | 10:10

Sorry, I misread your question, and my answer was about the Pentax K. The number of Pentar K was very, very low. Yes, 269$ seems a very low price.

28.09 | 15:31

Hi Bosse,

A near mint Asahi Pentar (yes Pentar) sold last month on ebay for £269. Were you aware of this? It seems like a very low price.

10.08 | 18:42

Hi Richard,
21.454 K models were produced between '58 and '59. But Pentax used the letter K for many other models, too. K-series in '75 and digital since 2006.

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