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PENTAX-110 20-40mm F2.8 Review RSS Feed

PENTAX-110 20-40mm F2.8

Reviews Views Date of last review
3 34,951 Tue November 24, 2020
Recommended By Average Price Average User Rating
67% of reviewers $40.00 6.33
PENTAX-110 20-40mm F2.8

PENTAX-110 20-40mm F2.8 PENTAX-110 20-40mm F2.8

A standard zoom for the Pentax Auto 110 system corresponding to 40-80mm in the 24x36mm format.

Max. aperture: f/2.8
Closest focusing distance: Unknown
Diagonal angle of view: 56 - 30 degrees
Optics: 8 elements in 8 groups
Filter diameter: 49 mm
Size: 54 x 45.2 to 65.4 mm
Weight: 174 g
Price History:

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Registered: January, 2011
Location: Skåne, Sweden
Posts: 482

2 users found this helpful
Review Date: November 24, 2020 Recommended | Price: $40.00 | Rating: 5 

Pros: Size, Fun, Cheap, 49mm filter size
Cons: Image quality, Lack of aperture control, inconsistent through the range
Sharpness: 3    Aberrations: 4    Bokeh: 5    Handling: 5    Value: 5   

This review is for a mint condition 20-40/2.8 bought second-hand in Sweden.

  • Fun
  • Cheap
  • Compact
  • Build quality
  • 49mm filter size

  • Soft
  • Inconsistent performance
  • Lack of aperture control

I have had five out of the six Pentax-110 lenses for several years now (lacking the Pan-focus), and used them on and off as fun lenses. A few things are inherent in the lenses as they where designed as super-compact somewhat cheaper lenses already from the beginning, e.g. the aperture control was in the camera body. There are still things to be said for each of the lenses.

I have used the 20-40 on both Micro Four Thirds and APS-C. On m43 it covers the frame during the entire focal range, but on APS-C it covers the frame only at the long end. Build quality is together with the 70/2.8 best of the Pentax-110 primes, mainly metal build. Zoom is push/pull type and the front rotates with focusing.

I had used the primes for some years when I purchased a mint 20-40/2.8 zoom. Especially the 50/2.8 and 70/2.8 primes was very impressive, so I had some hopes for the zoom. I am sorry to say it is of noticeable lower image quality. At or close to 40mm it gets very dreamy/soft look, lacking contrast and bokeh is bad (not even artistic fun bad like say a Helios-44). Both sharpness and contrast varies a lot in the focal range, but also the advertised "f/2.8" aperture gets a lot darker at the long end (at least one stop darker), so it takes some getting to know how to work with the lens.

I find that it performs best at shorter focal lengths and closer focusing distances, so I ended up using it mainly for close up work (sometimes together with a Hoya +3 closeup filter). Filter size is a positive, using very common 49mm filter shared with many Pentax lenses. Sharpness and contrast is much better at 20-30mm range, and bokeh has some character.

While being quite fun like the other Pentax-110 lenses, I think the lower and inconsistent performance combined with the higher price makes this the least attractive of the system. If you really need a Pentax-110 zoom this is the only choice, but I doubt that anyone needs that. My recommendation is to start with the 50mm prime first, as it is plenty available, best performance and covers APS-C fully. The 20-40 is still somewhat fun to use, and has it's place in a complete set.

Olympus E-P5, PENTAX-110 20-40mm F2.8@~20mm, 1/800 sec at f/2.8, ISO 200, Hoya +3 Close-up filter.

Olympus E-P5, PENTAX-110 20-40mm F2.8@~20mm, 1/320 sec at f/2.8, ISO 200.

Olympus E-P5, PENTAX-110 20-40mm F2.8@~30mm, 1/100 sec at f/2.8, ISO 500.

My PENTAX-110 pictures on Flickr
New Member

Registered: April, 2015
Posts: 12
Review Date: July 30, 2015 Not Recommended | Price: $40.00 | Rating: 6 

Pros: Well built, Smooth, Aasy to handle
Cons: Sharpness
Sharpness: 5    Aberrations: 5    Bokeh: 5    Handling: 8    Value: 6   

This lens I use on digital, crop. Of all the Pentax lenses I use I find this lens not sharp on the digital camera. I like the range, the price was more than fair, but I just can't be pleased with it. If you shoot film, (I heard the film is again available), this lens might work fine, but on crop digital, I am not crazy about it. This compared to the other lenses in the Auto 110 that are great performers in my opinion. I would still get it to have the whole set as GAS is forcing me, but...
Could be the lens, though I got it New in the Box, but again, doesn't ring my bell.
Giveaway winner!

Registered: December, 2007
Location: beantown
Posts: 944
Review Date: June 27, 2012 Recommended | Rating: 8 

Pros: Handy zoom range to walk around with
Cons: Not wide enough sometimes
Sharpness: 8    Aberrations: 8    Bokeh: 8    Handling: 7    Value: 8   

I will point out that this was used with Film

It is not a bad lens, but the other more smaller lenses makes this lens not always on the camera. It has good sharpness, but I must say that the cam inside is not always accurate and the very shallow rim for the front make this lens very prone to glare and loss of sharpness. So compared to the smaller prime lenses, the contrast is a little loose and it is at best a quick snap shot lens.

It still is a nice lens when you want more flexible and now a days you can cook in some contrast via post-processing. Consider getting an appropriate hood for it and be sure while zooming that you check your focus carefully.
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