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Camera User (?) Magazine Test Report - Asahi Pentax K Series

Publication date unknown

by Jeremy Haworth



At last its (sic) happened. Asahi Pentax, for so long the protagonists of the screw fitting lens mount in the East, have inscrutably change face and produced the Pentax series with bayonet mount. The New Generation cameras are examined by JEREMY HAWORTH.

WHY oh why? is the question everyone is asking. Admittedly, the 42mm screw mount was introduced by the East Germans, and has subsequently been used world-wide, none more than by Asahi Pentax.
The answer would seem to lie in the fact that these new cameras are certainly a whole new generation for Pentax, the last major step being the introduction of the original Spotmatic in 1964 which, apart from the inclusion of TTL metering in this camera, also saw a major redesign and improvement in the internal mechanisms, making for far greater endurance and reliability.
Briefly, there are three new cameras, all falling under the basic 'K' specification. The K2 is a fully automatic camera as far as exposure control is concerned, with manual settings possible [i.e. the replacement for the ES II and forerunner to the ME Super]. The KX is manual match-needle with a lot of features to improve handling and ease of use. The KM is a simplified version of the KX with lower specification [i.e. both where effectively replacements for the Spotmatic F, and forerunners of the MX]. Otherwise all three utilise the same body casing and bayonet lens mount and look very much the same from a small distance. So similar are they in many respects that the easiest course of action is to have a close look at the top K2 model, followed by points of detail on the KM and KX.

Ashai (sic) Pentax K2
The first thing about the K2 is that it is quite heavy - noticeably more so than screw mount Pentaxes. As such, it comes close to many other 35mm reflex cameras at 950g. The shape is much the same: it still looks like a Pentax. Dimensions are 145mm long, 93mm high and 93mm deep overall, depth when fitted with 50mm lens as reviewed.
Much has changed, and seemingly for the better. The lever wind is chunkier and has a fixed plastic end piece. Stand-off is considerable at about 25°, allowing most of the thumb to be placed between it and camera body for swift action. Winding is complete in a further single stroke of about 125°, a very convenient action which reflects the high gearing of this mechanism, emphasised by the firmness of the action. Quite a strong ball catch retains the lever in its rest position lying along-side the top plate, perhaps a trifle too firm for instant pick-up, especially if the hands are greasy.
Just ahead of the wind spindle is the frame counter window, showing even numbers white on black, dots representing the odd numbers. Clarity is good, the covering clear plastic being flat and not picking up difficult reflections. Along to the left is the shutter release button, sitting in a collar which forms a release lock; moving a stub arm left locks the button against release, revealing as it is moved over an orange warning mark on the top plate. Quite firm pressure is needed to trip the shutter, this being a common feature of most automatic cameras, while the Pentax K2 initial pressure has the function of switching on the exposure meter. This is cancelled when the lever wind I pushed home against the top plate. Here there is some slight complexity, which nonetheless should not affect the camera user in general. If the wind is pushed home, the meter will only operate be it on manual or auto, while the shutter button is partially depressed. If the lever is at stand-off, the meter remains on, even though first pressure has been taken off the button, only being cancelled when the lever wind in pushed to. In other words, a sensible way of making sure the battery is not left switched on while making the system active as soon as a move is made to make an exposure.
Completing the controls to the right of the prism is the shutter speed dial. Some 21mm in diameter, marked shutter speeds are from 1/1000th second down to a full 8 seconds, plus a B position, with separate 'automatic' marked in bright green past the top speed. This setting also covers the full time range, except that the actual time run can be any increment between the extremes, whereas the manual settings are only as marked, with strong click settings ensuring the positions. Once the dial is set on automatic, a small button on top has to be pressed to release it for travel on the other range. The top setting for electronic flash - 1/125th - is marked in orange, the others being in white, except for the peculiar distinction of the 2, 4 and 8 seconds in cream.
offset to the left of centre, the pentaprism makes quite a bulge in the camera's outline, made even more obvious by the hot-shoe fitted on top. This is clearly marked for X flash synchronisation, there being twin standard 3mm outlets for X and FP sync on the body's left edge. Covered with neat plastic caps, these sockets also feature a screw inner rim for a type of flash lead having a suitable securing device.
Far left is the rewind with fold-out crank. Sharply angled, this is fitted with one of the largest rollers the reviewer has yet seen. Furthermore, the end of the crank is well rounded, there being no chance of tearing skin on finger-tips with this one. Perhaps many years of pointing out this failing on cameras of every make have at last been noticed!
The base carries a coin slotted, clearly-marked cover for the twin silver oxide batteries, a deep tripod socket and shielded rewind release button. A novel point is that the battery cap has a plastic grip attached, which withdraws the batteries as the cover is removed. While the cover is marked with a dash to show negative, the correct way to insert the batteries is by no means obvious and clearer markings, even just a plus sign inside the battery chamber, would be an improvement.
The K2 is not without its complement of fixtures and fittings on the front, too. To the left of the lens mount is a strong spring loaded button which manually stops down the lens apertures for depth-of-filed preview. just beneath this is the delayed action lever. This can be set to any delay between about 5 and 11 seconds by moving the lever part of full way. Tripping is by fully pressing the shutter release, which provides the dual function offsetting the exposure if on Auto and releasing the delayed action, which may be cancelled after it has been set merely by returning the lever by hand to its rest position.
Beneath this is a black plastic press catch, the action of which is to withdraw the lens locking pin, permitting removal of this item, while on the other side is a slide switch, much the same as the meter switch on the Spotmatic, to raise the mirror. This can be one at any time, with the camera tensioned or not, the mirror staying up until the switch is moved down. Beneath this is the scale and button lock for film speeds, calibrated from ASA 8 to 6400, a wider range than previous models. This scale is clear, although of necessity small. The final control on the front is a manual override correcting the meter for certain unusual or specific situations by putting in one and two f/stop corrections over and under the 'normal'. Only criticism here is that, once altered, there is no reminder in the viewfinder or elsewhere that the meter has been set 'off norm'. So it is a case of having to remember.
One thing which the K2 has is a battery 'check', in the form of a small ruby light just to the left of the viewfinder eyepiece. Pressing a button by its side causes the light to come on if the power is still in good order. Final new addition is a slip-in panel on the back for the end tab off a box, as a type of identification.
Presently the cameras are available in the usual chrome and, in this case a rather smart-looking, coarse-grained platic covering on the sides. The chroming is the matter type becoming popular, with little tendency to show greasy fingerprints, as well as appearing hard wearing. Carrying is by two sturdy-looking strap lugs, mounted properly on the forward corners, providing good balance.

The interior
Access is gained in the time-honoured manner of pulling upon the rewind knob against stiffish spring resistance (Asahi Pentax seem to have uprated all their springs with this series!). The back swings open on a good hinge to reveal a smart and tidy interior. Tracking and register rails are 68mm in length, the pressure plate being just 4mm shorter Film feed is from left to right and is taken up with a reverse curl. Film flatness is aided by a roller on the back, not unusual in itself, but linked with a taper on the body casting leading on to the sprocket roller.
The mirror box is an example in design itself. None of the sides come flush with the film gate, which thus has its edges shielded. Both sides and the floor are covered in quite deep lateral ridges, stepped towards the lens top, in fact the underside of the mirror when raised, is finished in crackle black, as well as some ridges. Additionally, both top and bottom fall away, becoming wider as they approach the lens mount. This coupled with the dead matt finish, ensures an efficient, fare-free interior.

The viewfinder
The eyepiece is set in a large rectangular plastic frame carrying grooves down either side for attachments such as a right-angle finder. The view for spectacle wearers is somewhat limited, it not being possible to quite see all of the screen at one 'eyeful', although non-wearers should have no problems, provided they hold their eye close. The Pentax is neither a right- nor left-eyed camera; most users will find they have to squash their nose against the back.
The screen is essentially very fine ground glass overall. While there is a central disc without Fresnel brighteners beneath, the distinction between this and the remainder of the screen is negligible when the subject in nearly in focus. Critical focus is achieved by a fine mircroprism, this clearing to nothing as sharp focus is reached. As such, the screen is an excellent all-rounder for most lenses, especially long focus optics. Illumination is bright and even right into the corners, which are square cut, not rounded as many are to suit colour slide frames. Magnification is a little under life-size, when the 50mm lens is fitted.
Down the right hand side, but off the screen area, is the shutter speed scale, a duplication of the dial's figures, starting with Auto and 1,000 at the top, ending up with 8 seconds and B at the bottom. A transparent blue pointer shows which position the top dial is set, while the meter neede floats freely to show the shutter speed set if the system is on Auto, or what has to be set if manual is in use. The position of the needle is affected by film speed setting, any override set, ambient light and lens aperture.

The exposure Meter
The Pentax K2 has a silicon photo diode in place of the conventional cadmium sulphide (CdS) photocell. Advantages claimed are faster response time and better low light sensitivity coupled with a more linear reaction at extremes of light. Certainly, meter needle movements were very rapid as the camera was scanned over varying light intensities, which indicates that the auto shutter control would respond with sufficient speeds to almost any sudden swing of the camera. Low light sensitivity was also found to ne reliable, on a par with other high quality brands. In essence, the meter system delivered good exposures over a wide selection of conditions. Coupled with the use of the x4-x1/4 range switch on the camera front, even 'snap happy' use should ensure successful exposure every time.

The shutter
This is a completely new shutter for Asahi Pentax, manufactured by Seiko. Control is electronic on all speeds excepting the 1/125th for flash synchronisation. Metal blinds are used, consisting of five vertically running metal blades. Shutter and mirror operation combine to give a modest sounding 'clop' when released, while with mirror locked up the sound is shorter and crisper.

The lens
The lenses for the K series Pentaxes haven't changed specially for the event, but the mounting and general style of the 26 SMC Takumars has.
The first thing about the 50mm f/1.4 supplied is that the focusing grip is now covered with a large patterned soft plastic for secure hold. The mount is a little more chunky as a whole and most of the new series, extreme lengths excluded, now take 52mm screw filters, departing from the 49mm size which has been associated with this brand for so long.
The aperture ring is at the rear, with clearly marked figures, equispaced (sic) from 1.4 to 22. Whole f/stops are click set, again with very firm spring loading. Focusing in this case is down to the usual 45cm, 1 1/2ft, this range being covered in slightly over half a turn of the light focusing mount.
Major feature, of course, is the use for the first time by Asahi Pentax on the 35mm size of a bayonet mount. This is a three tab bayonet, locking by means of a pin protruding fro the camera flange locating the lens. Insertion and removal is by a fraction under a quarter turn. There are no external coupling links, diaphragm movement being relayed to the meter system by a shielded lever on both lens and body - nothing to get knocked. Diaphragm stop-down is served in a like manner. mouth size internally has been increased to 45mm, a significant gain over the previous 42mm. This has permitted the use of brand new lens, the 50mm f/1.2. Certainly, the mounting is robust and there were no obvious points of early wear.
Linked with the wider throat and the use of larger rear glasses for certain lenses, is a bigger mirror in the new Pentax. Somewhat deeper than hitherto, as the camera is released the mirror hinge mechanism rises slightly at the back before it begins to pivot up in the usual manner. This effectively prevents the mirror from clouting the rear element on its way up. Shake is supressed by a layer of high density foam plastic surrounding the whole of the screen frame, not merely along the front edge as is often found.
Optically, the lens is not changed from the existing 50mm f/14 specification, only in so far as the mounting. Briefly, this is a good performed wide open, perfectly usable in the central region albeit with some quite distinct softening towards the edges, much of this clearing up and the lens producing very good 'general purpose' images by f/2.Fromthen onwards it goes from strength to strength, being capable of top class results throughout its range, not only in terms of simple resolution, but also contrast and colour rendering, for it is, of course, anti-reflection coated to the Asahi Optical licensed SMC.

General conclusions
In short, an excellent camera, all the more welcomed for its use of bayonet lens interchange, which must do much to revitalise the Pentax's flagging popularity in professional spheres and sales lost to amateurs who decide they wanted this type of lens mount.
The feel of the camera is also that little bit more solid, although shape and dimensions have scarcely altered. The only averse criticism the writer feel he can make is concerning the viewfinder window and the difficulties attendant to spectacle wearer. While a larger window would cause a slight reduction in focusing acuity, at least it would be possible to see all the screen. And as there are more than 24 million people in the UK who wear glasses, this figure being reflected in other markets, this, surely, is something which the camera designers - all of them - should take account of? The other unfortunate point, sad to say, is that the price of the new range, not known at the time of going to press, will be 20-25% higher than the old series. That's progress!

The alternatives
As mentioned at the beginning, the K2 is now top model with the KX and KM acting as back-ups.
The KX uses the match needle system of exposure control in that the meter needle floats over the 1/1000th to 1 second plus B scale to the right of the viewfinder, its position dictated by the existing light collected via the full aperture metering cells (sic) and the position of the diaphragm ring. A blue needle also moves on the scale according to the position of the top shutter speed dial. When, by moving aperture of shutter speed the needles coincide, this is correct exposure. An additional point, found very useful, is an optical pickup on the pentaprism front which projects an image of the f/number set on the lens above the screen. Again difficult to see when wearing spectacles, unless the eye is tilted up.
Metering is as on the K2, centre-weighted using a silicon photo diode and powered by two batteries. Film speed is again ASA 8 to 64000 (sic).
Externally, the KX is much the same, detail differences being the lever wind, which may be inched on a ratchet: films speeds, set on a collar surrounding the rewind crank, which retains the old little, sharp, hurting design; battery check button on the top plate, pressing of which causes the meter needle to deflect to a fixed area on the finder scale; mirror lock-up, incorporated in the stop-down button as a collar - pressing the button stops down the lens aperture, doing so with the collar turned through a quarter raises and hold the mirror.
The shutter is a conventional cloth bind affair, horizontal running. Running times were found to be well within tolerance on the camera tested. All in all a nicely balanced modern camera.
Bottom of the trio is the Pentax KM, more comparable to the late range as it is essentially a Spotmatic F with bayonet mount. It has full frame average exposure metering, open aperture, using a CdS cell. Exposure setting is merely a case of centring the meter needle between two cut-outs by moving shutter of aperture controls. Film speeds are ASA 20to 3200, set on the shutter dial. Shutter and so for this quite conventional. A good solid camera having most of the necessary points - including a sharp rewind crank. How little things persist!
Accessories exclusive to the new series will have the letter K as part of their description. Essentially, there will be items connected with the new lens mount or new lens styling. Most other items are usable direct from the screw range.
Generally not much changed, apart fro the bayonet lens mount, with regards to the KX and KM, while K2 shows various detail refinements, such as the larger mirror with the impact-absorbing surround to all the screen and a significantly brighter screen to boot.

Obviously written for one of the lesser camera magazines, I feel I must almost apologise for reproducing such a dull review, written by someone who clearly wears glasses, has greasy hands with girly weak fingers, and finds many things too sharp for his delicate digits - but it is an authentic review from the launch of the K series.