Those Paragons of Pentax: The K-Series SLRs

Pentax KX with SMC Pentax 55/1.8 lens

   
​   The mid-1970s were a time of major transition in the SLR industry. The biggest changes involved the downsizing of camera bodies (initiated by Olympus), the general electrification and computerization of many functions (most notably with the Canon AE-1), and the inevitable de-contenting and cost-cutting that came with increased competition between all manufacturers for market share. Perhaps no series of SLRs demonstrated being caught in this no-man's land more than the first three models Pentax released with its brand-new K-mount bayonet in 1975. Two models would survive only two years, the third only five. Yet, ironically, the fourth model, introduced in 1976, would go on to be one of the most successful and iconic of all SLRs and would be in production for over 20 years. Fortunately for vintage camera lovers, any of these K-series SLRs can still be enjoyed and are serviceable even today. So let's take a look at the tragic trio of the KM, KX, K2, and the student camera extraordinaire, the K1000.    

  Origins of the K-Series

    It does not take much of a look at a K-model, particularly a KM or K1000, to see that the Spotmatic (1964-77) bloodline runs deep. The prism housing is more angular, but the overall body profile and control layout hardly changed. Which also meant that most of the internals were likewise identical in form, if not composition. For the two higher-end models, the KX and K2, there were improvements in metering, viewfinder displays, a metal vertical-travel shutter for the K2, and new mirror-lock-up (MLU) & depth-of-field (DOF) preview controls. But the most notable change for all of the K-models was their namesake, the new bayonet-style "K" lens mount. This was a result of a brief period of collaboration with Zeiss in the early 1970s. 

KM

SPOTMATIC

KM Top View

SPOTMATIC Top View

    
    ​Many people have wondered why Pentax even bothered with the K-Series when they debuted the compact M-series only a year later, in a clear response to both Olympus and Canon. A possible explanation lies in the fact that Pentax had been in a slow sales decline since 1968, and the greatest culprit was the antiquated M42 lens mount. While the other manufacturers had long before adopted modern, quick-action bayonet mounts, Pentax had hesitated to adopt one for its production cameras. It was not a matter of capability, for from the introduction of the SPOT-MATIC and Metalica prototypes in 1960 and continuing through 1966 with the Metalica II prototype, a bayonet mount was constantly present. Whatever the reasons for the delay, by 1973, with sales having fallen 40% from their 1967 peak, something had to be done. With pressure mounting, the fastest way to get the K-mount into production was to use the current Spotmatic F and ESII models with only the necessary changes for the new mount, while adding a couple of new features in the higher-end models. The K-Series would thus get the K-mount on the market and hopefully slow the bleeding while development of the M-Series continued. In other words, the Ks would be a temporary measure. But, oh what a measure! :-)

  Model-by-Model Profiles

   KM (1975)

• The KM was the original base model for the new series. And for a base model it was quite well equipped. 
• It was basically a Spotmatic F (formerly the top mechanical shutter, manual exposure model in the lineup) updated to K-mount. The two shared the same cadmium sulfide (CdS) meter, shutter, viewfinder display, top-deck control layout, and form factor. The KM did drop the shutter release lock of the Spotmatic F.
• A lens cover must be installed to prevent the meter from draining the battery when the camera is not in use.
• The KM featured a self-timer and DOF preview.
• Shutter speeds were 1/1000 - 1 sec. + Bulb. 
• ASA/ISO range is 20 - 3200. Meter sensitivity is 3 - 18 EV.
• The meter is powered by one 1.5V SR44/S76/357 silver oxide cell.  
• Weight was 622 grams (22 oz.)
• Discontinued in 1977; displaced by the K1000 

   KX (1975)

• The KX was intended as a new top-level mechanical-shuttered, manual exposure body. It had a control layout very similar to the ESII, the former top-of-the-line electronic model.
• There was a new, brighter match-needle viewfinder display that also showed the set aperture by means of a "Judas Window" that overlooked the lens' aperture ring. 
• Also new was a Silicon-Photo-Diode (SPD) meter offering greater sensitivity and faster response than the older CdS technology. Metering range is 1 - 18 EV. ASA/ISO range is 8 - 6400. The ASA/ISO dial was concentric to the rewind crank as on the ESII.
• Shutter speed range was the same as the KM.
• The KX featured a combined DOF preview button with a surrounding lever for MLU capability. (It looks like they lifted it right off of a Nikon F2 ;-)) It also adopted the Nikkormat-style meter switch design of pulling out the film advance lever until a detent is engaged to turn the meter on. It's OK for right-eye users but a pain for left-eye users. The first K-lenses also had a standard filter ring diameter of 52mm instead of the previous 49mm favored by Pentax (and that they would go back to with the M-Series), the same as Nikkor lenses. Hmmm, it seems like Pentax was very interested in Nikon during K-series development ;-). Funny too, that Nikon had nearly doubled their sales from 1971 - 73. Ahh...probably just coincidence.
• It used two 1.5V SR44/S76/357 batteries.
• The greater weight and MLU function of the KX make it a better candidate than its successor, the MX, for reducing the effects of vibration in the shutter speed ranges of 1/30 to 1 sec. for macro, telephoto, or low-light photography.
• Weight is 631 grams (22.2 oz.)
• Discontinued in 1977; Replaced by MX 

   K2 (1975)

• The K2 was the direct descendant of the M42-mount ESII, with an electronically-controlled shutter and aperture-priority as well as manual exposure. 
• The K2 featured a metal Seiko vertical-travel shutter covering 1/1000 to 8 sec. speeds. This was an adoption of the shutter configuration found in the Metalica II prototype of 1966 and an improvement on the horizontal cloth shutter of the ESII. It enabled a higher flash sync. speed of 1/125 sec instead of 1/60.
• It had a single mechanical back-up speed of 1/125 sec. along with mechanical Bulb setting instead of the range of 1/60, 1/125, 1/250, 1/500, 1/1000 sec. on the ESII. 
• The K2 had MLU, DOF preview, and self-timer.
• It shared the SPD meter of the KX and the viewfinder display was quite similar, only having an extended range of shutter speeds for the match-needle, and oddly, it omitted the aperture display window. (This would be rectified in the K2DMD, a later motor-drive capable version.)
• ASA/ISO range was the same as the KX, 8 - 6400, but the control for it and exposure compensation (-2EV to +2EV) was concentric to the lens mount (resembling the Nikkormat shutter speed/ISO control). This control is notorious for getting stiff because of dried-out lubricant, but is easily serviced.
• The K2 had a shorter film advance throw of 130 degrees instead of the 160 degrees of the ESII and the other K models. It used the same meter switch as the KX.
• The K2 takes the same batteries as the KX.
• Weight was 680 grams (24 oz.)
• Discontinued in 1980. The K2 did not have a direct replacement. Its market position was split into two. Succeeded by the ME super in the amateur lineup and by the truly professional-level LX.

   K1000 (1976)

• The quintessential student camera, the K1000 was basically a K-mount equipped SP1000, the former base model of the Spotmatic line. By deleting the film information dial, self-timer and DOF preview button from the KM, Pentax came up with the K1000. It was an immediate hit, and the KM quickly became superfluous in the K-lineup and only lasted for a year after the K1000 was introduced.
• The K1000 would go on to be one of Pentax' all-time most successful models, selling well over three million copies over 20+ years. Production was moved twice, from Japan to Hong Kong (1978) and then to China (1990) to cut production costs. Plastic top and bottom plates and other internal cost-cutting measures were adopted over the years to fight inflation.  
• The most desirable K1000s are the Japanese-produced models, followed by the early-production Hong Kong version which consisted of parts made in Japan and then assembled in Hong Kong. The cheaper plastic-plate version appeared in the late-1980s. The most notable difference is the higher quality of the film advance in the earlier models.
• If you are thinking about K1000, seriously consider a KM in today's market. Nostalgia seems to play a big role in the robust prices of K1000s and the KM is almost forgotten because of its short production life and can often be had for the same or even less money. The user experience is identical, except for having the self-timer and DOF preview capabilities with the KM. 
• Weight was 620 grams (22 oz.)
• Discontinued in 1997

    K2DMD (1976)

• The K2DMD (Data Motor Drive) was an improved K2 with motor drive capability. They are quite rare and command the highest prices of any K-series camera. The Motor Drives and Data Backs are extremely rare and quite bulky.

 
   Other Improvements over the K2:

• Aperture Read Out in the viewfinder, vis a vis the KX
• Exposure Compensation Warning. Whenever exposure compensation is engaged, the aperture readout in the viewfinder changes to orange from white to alert the photographer.
• Built-in Eyepiece Blind. This is engaged via the shutter speed dial to block extraneous light from entering the viewfinder and skewing the meter reading when the photographer does not have their eye to the finder. It is only available in Automatic (aperture-priority) mode. 
• Low Battery Voltage Warning. This feature locks the shutter and mirror in the up position when voltage is too low to cycle the shutter. This is a final warning to replace the batteries. Turning the shutter speed dial to B will reset the camera. Thank you Minolta XE-7 :-)
• Photo Memory Lock (or AE lock in modern terminology). By pushing the MLU lever down the current exposure reading is locked in, allowing the photographer to recompose while retaining the desired settings. Only available in Automatic mode.
• Extended Photo Memory. This is engaged when the mirror is locked up and will hold the exposure reading for up to 10 minutes. Also only for use in Automatic mode.
• Split-Microprism focusing aid. Pentax finally offered a combined split-image rangefinder and microprism focusing aid in a camera.
• Interchangeable backs. The K2DMD was the first Pentax to accept a Data Back.
• Weight is 685 grams (24 oz.)
• Discontinued in 1980. Succeeded by the LX (Pentax' first true professional SLR)

  Comparisons and Conclusion

   The K-bodies provide some interesting possibilities as far as the vintage SLR experience goes. If you are looking for the Spotmatic experience without the quirks of the screwmount, or fiddling with o-rings and batteries, the KM and K1000 are prime options. Dead-simple operation, metering, and proven reliability make them a great choice for beginners or anybody who wants to get back to the basic nuts and bolts of photography. K1000s have great appeal nostalgically for many people, but we would recommend a KM due to the inclusion of DOF preview and a self-timer. And they often sell for the same or less than K1000s, due to their relative obscurity. KMs generally range from $60 - 150 USD and K1000s occupy that same range but, inexplicably (except for sentimental reasons), will routinely sell for $200 - 250 USD. There is definitely no need to pay that much if you are considering one ;-). And go for an early production (Made in Japan or early Hong Kong) K1000, if you really want one.

   The KX is one of our all-time favorite SLRs here at 678. It has a great meter and viewfinder, a fully mechanical shutter, MLU, DOF preview, and self-timer. Shooting one back-to-back with a KM, you'll notice the better viewfinder, the more-precise match-needle metering, and the film winding is smoother, which fits with its higher slot in the lineup. If we could only have one K-Series body, this would be it! A KX is a rarer beast than a KM, but can often be found in excellent condition at the higher end of the same price range. They are definitely worth it in our estimation.

     Which finally brings us to the K2. The DMD version is definitely the most desirable of the two from a features/collectability standpoint. It was the absolute top-end Pentax until the debut of the LX in 1980. And it was priced accordingly ;-). Inflation-adjusted (2016) MSRPs for the body, data back, and motor drive are: $2,700.00, $1,900.00, and $1,368.00, respectively. That comes in just under $5,000 retail for the whole package (that makes that new K-1 seem like a pretty decent deal now, doesn't it? :-)). Needless to say, not a lot of DMDs (which came only in black) sold, making them rare birds then, and even rarer now. The standard K2 (black or chrome) sold for about $400 less. So, is a K2 in the cards for you? The biggest issue today is electronics, particularly circuit boards (common to all '70s electronic SLRs). Simply put, new replacements have long been unavailable if yours gives up. The only option is cannibalizing another body. If you have a working K2, shoot it 'til it dies (and it may not die for a long time ;-)). If you can get your hands on one that has been CLA'd (Cleaned, Lubed, Adjusted), that is preferable, as you'll know that it is working for sure. In operation, the K2's only real quirk (for many people, anyways) is its ASA dial. Its location (surrounding the lens mount) and operation (follow the technique in the manual, exactly!) can be off-putting for some. Standard K2s fall into the same price range as the other K-bodies, which, if you can find one in excellent working condition, makes them a pretty-decent deal considering their original pricing. The rarity of the DMD puts it into a completely different bracket. Excellent condition CLA'd examples will fetch upward of $400 USD sometimes.   

     Although short-lived, the K-Series managed to stanch the sales decline of the previous seven years for Pentax in 1975. Sales nearly doubled for that year, and without the K-family, there would have been an eighth year of sales slippage. With the introduction of the M-Series in 1976, the K's days were numbered...except for the K1000. Its annual sales for the next 18 years would average 150,000 units. If you took photography in high school in North America in that era and beyond, 9 chances out of 10 the camera you found in your hand was the K1000. As for the rest of the Ks, they faded rather quickly from the public eye. But, in the hands of loyal Pentaxians, they just kept on clicking, often remaining a favored model even when newer, more complicated, more plasticky Pentaxes popped up. ​

 
  References:

     Pentax KM, KX, K2, K2DMD, & K1000 Manuals @ www.butkus.org
     The K Series 1975 - 97 @ http://www.pentax-slr.com/71760557
     Pentax Manual Focus Film SLRs @ www. pentaxreviews.com
     Popular Science April 1977 @ https://books.google.ca/books
     Project SLR Production Numbers: (Asahi) Pentax @ www.knippsen.blogspot.ca