Comparing inexpensive Pentax zoom lenses, part I – telephoto lenses

My journey with digital photography, as a hobby, started with Pentax K100D Super, and an 18-55mm kit lens. In those early days, I really wanted a telephoto lens.

Specifically, I wanted the other, telephoto kit lens – smc Pentax-DA 50–‍200mm  F4–‍5.6. Here, it will be compared to a similar, film-era lens – smc Pentax-FA 70–200mm F4–5.6.

Note: Unfortunately, I got the idea about this article after I’d already returned DA L 50–‍200mm lens, I have no side-by-side photos, and I haven’t specifically taken photos that would fairly represent the optical properties of that lens. So, no direct comparison photos, you’ll have to trust my judgment. More photos will follow.


Somehow, I never found a justification to get the 50–200mm lens – I started discovering film photography, so my money went to manual-focus lenses I could use equally well on my Pentax MX film camera. At the same time, I wasn’t really sure if I knew how to use a telephoto lens, I started living on my own, money was scarce, so I discovered cheap, old, manual-focus telephoto lenses. Some of those lenses turned out to be reasonably good, some not so much, but all served their purpose – providing me with some telephoto reach and proving to me I’m not really a big fan of shorter telephoto focal lengths. Meaning, I didn’t get to buy my “vaunted” 50–‍200mm kit lens.

After that early period, and after learning a lot and meeting a bunch of enthusiast photographers from the area, I managed to borrow and use all other Pentax-DA telephoto zoom lenses – DA 55–‍300mm F4–‍5.8, DA★ 50–‍135mm F2.8 and DA★ 60–‍250mm F4. I did not like the 55–‍300mm and loved the 60–‍250mm. Regardless, after some time, I moved out of the system and ended up using Pentax K-mount for film only. So, I didn’t get to buy my own 50–‍200mm kit lens.


Sometime later, I did manage to get a relatively modern, autofocus telephoto lens, just not the one I wanted – I got smc Pentax-FA 70–‍200mm F4–‍5.6. This lens was perfectly usable on both film and digital cameras and had a proper aperture ring, autofocus, power zoom and everything. With almost the same reach and with the same aperture range, it was as close as possible to my wanted lens. All was well, it was just that I didn’t really use the lens – it’s pretty big and heavy, and autofocus speed isn’t something to write home about – a typical, lower-end telephoto lens from the later film era.

Finally, after more than a decade, and boring all the readers, I recently finally managed to get a hold of that vaunted smc Pentax-DA L 50–‍200mm F4–‍5.6 lens! Contrary to Canon’s terminology, on Pentax lenses, L stands for the lightweight kit lens version, with a plastic mount and no QuickShift focusing, but hey, it’s the DA 50–‍200mm, the lens I always wanted!

The experience

Finally, let’s compare the cheaper, DA L version of the 50–‍200mm kit lens and the old FA 70–‍200mm lens, then! Both lenses cover almost the same focal length range, with almost the same aperture range. Both can autofocus, and both will work perfectly fine on any Pentax K-mount DSLR.

FA 70–‍200mm has an aperture ring, making it more suitable for older, manual film cameras and some autofocus film cameras. It is well-built, feels pretty sturdy, it has a Power Zoom clutch for enabling/disabling motorized zooming, it has a metal lens mount – no weight-saving plastic mount here! Although the motorized zoom mechanism can provide a consistent focusing speed and some interesting special effects while recording video, on this lens, there is some wobble of the internal lens tube, and the front of the lens rotates while focusing, so using polarizers or petal hoods is not an option. As expected, there is no bayonet mount for a hood.

DA 50–‍200mm is significantly lighter and smaller, it extends quite a lot more than the other lens. The front element does not rotate while focusing or zooming, and there is a bayonet mount for a hood. It has a plastic, weight-saving lens mount, but there is no aperture ring here, anymore, and the QuickShift mechanism is omitted. Build quality is reasonable, nothing to write home about, but there’s nothing wrong with it, also – it is a visibly budget lens, and it does not try to hide it.

Using both, differences are becoming obviously clear.

Sharpness is similar, both lenses are acceptably sharp, with the newer, DA 50–‍200mm lens having a slight edge, but the autofocusing speed of the newer lens is just in the next league – it simply focuses significantly faster than the older, FA 70–‍200mm lens. Handling on bigger bodies, like K20D, is similar, but on smaller bodies, like K-x, and most MZ-series film cameras, the lighter and smaller lens feels much easier to use. Also, since FA 70–‍200mm is a rather long and heavy lens, it can out-balance lighter cameras on less sturdy tripods.

Using DA 50–‍200mm lens on film is not recommended, it does not cover the full 35mm film frame, and it vignettes strongly, with fully black borders, despite the fact that in the viewfinder it looks just fine. The lack of aperture ring is also a significant drawback, it can be used only in full automatic, Program and Shutter priority modes.


While optically there is not a huge difference between DA 50–‍200mm F4–‍5.6 and FA 70–‍200mm F4–‍5.6 lenses, in day-to-day practice (and theory, as well), for most Pentax DSLR users, a newer, DA lens is an easy choice, a no-brainer. It focuses quickly, it is sharper, it is well-balanced and reasonably well-built, and it does its job perfectly fine, every time – even the budget, DA L version.

Pros and Cons

smc Pentax-DA L 50–‍200mm F4–‍5.6 ED


  • Image quality
  • Range
  • Autofocus speed
  • Size
  • Weight


  • Build quality
  • 6 aperture blades
  • No QuickShift
  • Plastic mount

smc Pentax-FA 70–‍200mm F4–‍5.6


  • 9 aperture blades
  • Build quality
  • Power Zoom feature
  • Price (used)


  • Size
  • Weight
  • Noise
  • Design


Comparison table with the most significant differences.

DA L 50–‍200mmFA 70–‍200mm
Year of introduction2008.1991.
Image coverageAPS-CFF
APS-C equivalent focal length~75–300 mm~105–300 mm
Aperture rangeƒ/4 – ƒ/22
ƒ/5.6 – ƒ/32
ƒ/4 – ƒ/32
ƒ/5.6 – ƒ/45
Optical formula11-1010-8
Aperture blades69
MFD1.1 m1.1 m
Filter diameter52 mm52 mm
Length78.5 mm117 mm
Diameter66.5 mm73 mm
Weight235 g465 g
DA L 50–‍200mm F4–‍5.6 vs. FA 70–‍200mm F4–‍5.6
smc Pentax-FA 70–‍200mm F4–‍5.6
smc Pentax-FA 70–‍200mm F4–‍5.6
smc Pentax-DA L 50–‍200mm F4–‍5.6 ED