Pentax-A 50mm f/2.0 SMC 193

Pentax-A 50mm 2.0 SMC 0-1

Pentax-A 50mm f/2.0 SMC. If you’re looking to purchase this lens I always check Adorama and Ebay for good deals. It helps me if you purchase it through one of these links here in this review. When you purchase through these links it financially enables me to devote time to develop this site further. Thanks for the help! -Todd

Pentax-A 50mm 2.0 SMC 0-2


5.2 oz (148g)

Focus Ring
Rubber on Plastic.

Close Focus
1.55 feet (0.45 meters).

Filter Threads
49mm, Metal

Aperture Ring

6 blades stopping down to f/22.

Pentax A Metal Mount.

Made in

f/2 | f/2.8 | f/3.5 | f/4 | f/8


100% Crop

f/2 | f/2.8 | f/3.5 | f/4 | f/8


Corner at f/2

Corner at f/2

f/2: A little soft with a fair bit of chromatic aberration and spherical aberration reducing contrast.
f/2.8: Nicely sharpens up with better contrast and still some chromatic aberration.
f/3.5: Very sharp with nice contrast and a little chromatic aberration.
f/4: Sharper yet with almost no chromatic aberration.
f/8: Just continues to get sharper.

There is a fair bit of vignetting at f/2 but quickly starts to clear by f/2.8 and almost gone by f/3.5 and only a hint by f/4.


The blur is ok but not great and a little distracting.

f/2 Bokeh

f/2 Bokeh

f/2 Bokeh 100% Crop

f/2 Bokeh 100% Crop


Only a tiny amount of Barrel Distortion.


On MF Camera
Optics:         ★ ★ ★
Mechanics:  ★ ★ ★
Ergonomics: ★ ★ ★ ★
Usefulness:  ★ ★ ★
Availability:   ★ ★ ★ ★
Overall:         ★ ★ ★

On AF Camera
Ergonomics: ★ ★ ★
Overall:         ★ ★
Out of 5

This is a swell little pancake lens that is fairly light and built well. Optically this lens is pretty sharp wide open but has a fair bit of chromatic and spherical aberration. The lens has a little low contrast, but simply stopping it down to f2.2 and f/2.5 really cleans the images up. There are 2 versions of this “A” lens. The older one has a metal aperture ring and the newer one has a plastic aperture ring. I found the metal ring easier to feather between stops to get f/2.5 and such. This lens has really nice contrast, color, and low distortion.

If you find one they are fun to play with and really easy to use! Although they are mostly plastic, they are still a really well built lenses and relatively easy to find.


Did this review help?
My hopes are to take the time to continue developing this website with more test photo based reviews. If you are ever interested in purchasing this lens or other photography equipment please do so through these links here in this review. I always check Adorama and Ebay for good deals. This helps support my family and allows me to take more time for the site. The best part is this site is free for you and I link good deals I find!

Sometimes these links will actually give you better deals then typical retail prices! I personally buy from the links I have listed whether looking for new gear or fun old stuff. I can personally attest to their good & safe service from years of experience. Thanks again to you, our readers, for supporting us! -Todd