All posts by Kevin Campbell

pentax auto 110

Background

This is a real oddity, a precision SLR designed around the tiny 110 film format. Pentax introduced this in 1979, at a time when electronic exposure controls could be miniaturised to the point where they could be used in a device this small. And it’s really, really, small!

Technical Details

This is the only interchangeable lens SLR ever produced for the 110 film cartridge – there were fixed lens 110 cameras from other manufacturers. It offers program only TTL auto exposure, and a range of 6 lenses in the Pentax 110 Bayonet format:

  • 18 mm f/2.8 wide-angle lens (equivalent angle of view to a 35 mm lens on a 135 format camera).
  • 24 mm f/2.8 normal lens (equiv. 50 mm). The optical design meant that this was the smallest lens on the system.
  • 50 mm f/2.8 telephoto lens (equiv. 100 mm)

In 1981, three more lenses were included:

  • 18 mm “Pan Focus” lens was a compact lens of fixed focus set to the hyperfocal distance; the short focal length and wide aperture meant that its depth of field stretched from 1.75 m (5.7 ft) to infinity. The camera aperture needed to be set at f/6.3 for this lens to work as intended.
  • 70 mm f/2.8 telephoto lens (equiv. 140 mm)
  • 20–40 mm f/2.8 zoom lens (equiv. 40–80 mm). This lens extended for wider focal lengths and shortened towards the telephoto end.

The Museum Sample

Found, as usual, on eBay complete with flash, filters, case, and all the original manuals for $90. It’s generally quite clean, but the 110 film is tough to find and so difficult to tell if it still works.

The flashgun, tiny as it is, still dwarfs the camera itself.

Pentax spotmatic spII

Background

Introduced in 1971 along with the line of S-M-C Takumar lenses – though still all metal without the rubber grips found on the later models on the SP F. Compared to the original Spotmatic the film transport was improved, as was the light meter. A hotshoe was now included in addition to the standard flash connection.

Technical Details

M42 screw mount lenses support automatic diaphragm for exposure, but manual stop down is required for metering – that’s the lever to the photographers left of the lens mount. Horizontal travel, rubberized cloth shutter offering 1s to 1/1000th is as standard as they come, including flash sync at 1/60th. Metering is of the simple match needle variety through the viewfinder, which features a fixed, ground glass screen with micro-prism center circle. Compared to the prior model the ASA range is now expanded to 3200.

The Museum Sample

Acquired October 2020 through eBay for $140, this is a nice clean sample. As is common for US market Pentax cameras of this era, it’s branded as a Honeywell Pentax.

Additional Info

  • Manufacturer:Pentax
  • Year Introduced:1971
  • Year Discontinued:1976
  • Film format:35mm
  • Serial Number:5013378

Pentax Spotmatic F

Background

Launched in 1973, the Spotmatic F was the first Pentax to offer open-aperture TTL metering – 7 years after rivals had first offered the feature. It’s visually very similar to other Spotmatic models, and continued the tradition of refinement and quality in the hand.

Technical Details

In common with the other late models in the Spotmatic line, the F offers an expanded light meter sensitivity range of 20-3200 ASA, up from the 20-1600 of the earliest models. The biggest advance, as already noted, was the introduction of open aperture metering. Unlike earlier models where the meter was activated by a switch which also stopped down the aperture, the F utilizes a new coupling on the SMC Takumar lenses to communicate the selected aperture to the metering system.

Other than the change to metering, the chassis is fundamentally similar to earlier models: a cloth, mechanical shutter offering 1-1/1000 sec range with flash sync at 1/60sec. at 642g weight is very close to the original SP and SPII.

Why it’s special

The first Spotmatic to offer full aperture metering. It also introduced us to the SMC Takumar lenses, which in 42mm screw mount still look very similar to the first generation of K bayonet mount lenses.

The Museum Sample

Acquired in October 2020 with a SMC Takumar 50mm f1.4 for $95, complete with ever ready case and owner’s manual. This is a nice honest sample with little signs of abuse or wear.

Additional Info

  • Manufacturer:Pentax
  • Year Introduced:1973
  • Year Discontinued:1976
  • Film format:35mm
  • Serial Number:6172372

Canon F-1

This represents a turning point for Canon: their first professional grade camera, introduced in March of 1971 along with a new lens mount – the FD range.

The F-1 established it’s pro-credentials by offering a huge range of interchangeable parts – viewfinders, focusing screens, winders, backs – and a range of flash accessories. Also notable was the 1/2000s top shutter speed

A number of interesting technical solutions are seen with the F-1, including TTL metering achieved by locating the meter cell at the side of the focusing screen, where light was directed to it by a small mirror. This allowed metering to be independent of the finder attached, much simplifying things.

One of the most curious accessories was the Servo EE finder, a bulky finder made even bulkier by the battery pack it needed, holding 8 AA cells. This finder incorporated a servo motor – hence the name and the need for all the batteries – which mechanically connected to the shutter speed dial in order to change speed based on metered light and selected aperture.

Canon Pellix

This is a definite odd-ball, and example of creativity attempting to solve an engineering problem: how do you capture light coming through the lens for metering purposes?

The Canon answer was to use a pellicle mirror; one which allows about 2/3rds of the light to pass through, and diverts the remaining 1/3rd to a light sensor. The mirror is fixed, and remains down during exposure. The CDS meter cell is moved into the path of the light by pushing the self timer towards the lens barrel, which also causes the aperture to stop down.

In order to keep light from the viewfinder from influencing metering, there’s even a blind that covers the eyepiece – operated by a ring around the rewind knob.

There are disadvantages to this approach, primarily that there’s about a 1/3rd stop loss in light transmission. To compensate for this the Pellix was supplied with a 55mm f1.2 lens – the museum sample has the FL50mm f1.4.

Advantages are several however:

  • Less vibration due the absence of mirror slap
  • Quieter operation
  • No viewfinder black-out during exposure, making tracking shots easier
  • The rear element of lenses can protrude further into the body, permitting a compact design

Olympus OM10

In 1972 Olympus introduced their OM line, and reset consumer expectations for the size and heft of a 35mm camera body. The various OM1/2 variants were very successful and so, in 1979, the OM10 was introduced at a more amateur friendly price point.

During the time when I studied photography at school – 1979-1981 – the OM10 was heavily advertised in the various photo rags of the time. Construction was a little less robust than the pro oriented single digit models (OM1 etc), but price was commensurately lower and it still accepted most of the OM line of accessories.

In standard configuration the OM10 is aperture priority only, much like the Pentax ME/MV, but a rather dinky little manual adaptor was offered – and which is fitted to this example. The manual adaptor allows the user to select the shutter speed when the primary dial is set to manual by way of a rather clumsy slide switch. It’s a very simple affair comprising of nothing more than a calibrated knob and a mini headphone jack. I strongly suspect it’s nothing more than a well calibrated variable resistance.

There are a couple of aspects of the OM line that are noteworthy, including the presence of depth of field preview built into the lens rather than the body. There’s a little tab on most OM lenses which sops down the aperture mechanism. While on the subject of OM lenses, it’s noteworthy that the aperture ring is at the front of the lens rather than at the rear – where almost every other maker put it. Personally I’m not a fan of this approach.

While smaller than the prevailing 35mm bodies when the OM line was launched in 1972, but the late ’70s Pentax had shown us what was possible with the ME line. The OM10 is bigger and feels crude by comparison – dials seem plasticky and finicky to operate compared to the ME derivatives.

The museum example seems to be in pretty decent working order – the battery is still operational, the shutter speed lights up in the viewfinder and the electronic self timer works. It even has the iconic Japanese Camera Inspection Institute quality control sticker intact 🙂

Pentax KM

Essentially an Spotmatic F, the KM is what many feel the K1000 should have been. Introduced alongside the KX in 1975 as it’s less expensive sibling, the KM still offered a self timer and depth of field preview – both features that were thought to be omissions from the K1000. Interestingly, the depth of field preview lacks the lock-out feature found on the KX.

The meter is a little less sensitive than that in the KX, and the film speed range a little smaller. There’s no aperture window in the viewfinder, but there is the ability to record either the number of exposure or the type of film using a small wheel under the rewind knob.

As with the KX the KM was offered in both chrome and black, though I’ve never seen either in anything but chrome. They weren’t made for more than 2 years, and so there are relatively few still around. This one was pretty dirty when received, but has cleaned up somewhat.

Pentax KX

1975 saw the introduction of the KX as the advanced-amateur model in the Pentax K series lineup, seen as one step up from the KM. As with all the K line, the body is essentially a bayonet mount development of the Spotmatic line, and physically very similar.

Metering is of the match needle variety, and the display shows both selected shutter speed and the speed required to achieve “correct” exposure. The pentaprism window looks out onto the aperture ring, so the selected value is also visible through the viewfinder.

As the advanced member of the lineup, the KX also offers mirror lockup, a self timer, depth of field preview (with a lock-out feature) and a switch for the light meter. It’s otherwise similar to the K1000 – the VW Beetle of film cameras – in that it’s pretty heavy, solid, and decidedly mechanical in use.

Pentax MV1

Surprisingly, given it’s decidedly amateur auto-only positioning, this MV1 was “rode hard and put away wet”. It’s one of the most used models in the museum, and was filthy when received. I’ve included it as an interesting reminder that even supposedly beginner friendly cameras can earn their keep through hard work.

Introduced in 1980, the MV1 is a little less basic than the MV it succeeded – it has a self timer for example, a memo holder, it can accept a data back and – as with this example – a winder. It’s still aperture priority only, with an electronic, focal plane metal shutter. It’s very clearly a member of the ME family, with the same almost implausibly compact body and featherlight controls.

It’s still very much a beginner friendly camera, and the shutter speed isn’t displayed in the finder. Interestingly there is exposure compensation, though it’s a little hidden beneath the rewind lever and requires good fingernails to operate.

Pentax MX

Introduced in 1977, and produced until 1985, the MX represented the flagship of Pentax’s 35mm line. Unlike the ME and derivatives, it features a mechanically timed, cloth shutter. It’s smaller and lighter than the KX, which it succeeded, but other than the overall body form factor it shared little with the ME range. Only light metering required a battery, for example, and there were no automatic metering modes offered.

As the “professional” model in their line, the MX offered interchangeable focusing screens, a choice of data backs, a bulk film back, and both a winder and a motor drive. There’s a small window built into the finder pentaprism which peeks out at the aperture ring, and lets the shooter see it through the finder. It’s a solidly built, well crafted piece of jewelry.