Konica Hexar
From Silvergrain Labs
Wanted: I'm looking for an inoperative Konica Hexar AF (any variety).
Specifically, I need this part:
Functionality and cosmetic condition of the camera is irrelevant. If you have an inoperative Hexar (beyond economical repair) and can give it to me, pleaes let me know!! Thanks!! Ryuji
Konica Hexar AF (black) (コニカ ヘキサー AF ブラック)
Original Konica Hexar is often called "Original Hexar," "Hexar AF," or "Hexar Black" to remove confusion with Hexar Silver (AF model) and more recent Hexar RF. Hexar Silver is a slightly modified version of Black, with extra functionalities but the silent mode removed. Hexar RF is a completely different camera using rangefinder (not autofocus) and interchangeable lenses on KM-mount (or M-mount).
Hexanon 35mm f/2.0
Hexar AF models are equipped with a fixed Hexanon 35mm f/2.0 lens (7 elements in 6 groups), derived from Xenotar. There is a speculation that Hexanon 35mm f/2.0 was a close copy of Summicron on M mount. However, if you read the Konica technical report on this camera (see below), it will be apparent that the design is more akin to W-Nikkor 3.5cm f/1.8 and also Hexanon incorporated its own modifications required by the camera design. (Both Hexanon 35mm f/2 and Summicron 35mm f/2 are derived from W-Nikkor 3.5cm f/1.8 design.) The originator of this type of design was W-NIKKOR 3.5cm f/1.8 but this Hexanon incorporates modification that was necessary to accomodate electrically controlled shutter and aperture diaphragm in the lens unit.
Hexanon 35/2
W-Nikkor 35/1.8 (from Nikon website)
The main difference between Hexanon 35/2 and W-Nikkor 35/1.8 is that the second and third elements are separated in Hexanon. This gives greater negative power to the front group of the Hexanon, which allowed slightly larger spacing between the front and rear groups, in which the electronic shutter and diaphragm assembly were placed. (That is, Hexar AF needed some extra space to pack lens shutter and electronic motors to drive the shutter and aperture diaphragm, and this is reflected in the Hexanon lens design.)
Another difference between Hexanon and W-Nikkor is that the last surface (the rear surface of the cemented group) is negative in W-Nikkor and positive in Hexanon. This last group is placed behind a Xenotar-type lens to correct for coma, spherical aberration, field flatness and other important factors as the whole system. It is very likely that Konica engineers redistributed the balance of positive and negative powers in the rear group as well, and also optimized for aberrations in a slightly different way. One aspect is below:
The sperical aberration of Hexanon 35mm f/2.0 is undercorrected to ensure crisp high contrast image from f/2 wide open. This is a very unique point of this lens design. Most rangefinder and SLR cameras fully correct or even overcorrect for sherical aberration so that the plane of focus does not move when the lens is stopped down. Hexar AF, on the other hand, can calculate the focus offset for each aperture value and correct for the focusing error during exposure.
One advantage of undercorrecting spherical aberration is that the lens can deliver quite good image contrast wide open. The MTF at f/2 (top) for 10 lp/mm is very good for 70% of the image area, although the performance worsens near the edge, as expected. The MTF is truly excellent when stopped down to f/5.6 (bottom). Another advantage of undercorrection is very soft blur in out of focus area (bokeh). The image character varies widely from wide open to f/4 range. (When stopped down to 5.6 or 8, the lens becomes just another excellent lens.)
Very accurate active AF system
Hexar uses very simple center-only AF, but it uses 3 windows for the AF system. The center window is to emit infrared spotlight for active AF. The left and right eyes are photodiode sensors. This placement can cancel focusing errors that occur in difficult situations, as described in the diagram below:
| Major specifications of Hexar AF Black | |
|---|---|
| Filter thread | 46mm |
| Aperture diaphragm | f/2 to f/22 |
| Lens construction | 7e 6g, very similar to W-Nikkor 3.5cm f/1.8 but with the second and third elements separated. |
| Exposure Meter | silicone photodiode: center weighted (15˚, EV 0-16), spot (4˚, EV 3-18) |
| Film speed | Meter manually set from ASA 6 to 6400, and DX code from 25 to 5000. |
| Self timer | 10 seconds (electronic) |
| Auto power off | about 2 hours |
| Multiple exposure mode | No. of exposure is unlimited but displayed to 9. |
| Autofocus | Infrared active 3-eye system, 290 steps |
| Focusing range | 60cm to infinity |
| Battery | 2CR5 for the camera, and |
| CR2025 for date function | |
| Shutter speed | bulb and 30s to 1/250s |
| Size | 137.5 x 76.5 x 67.5 mm |
| Weight | 495g. |
| The MSRP | 88000 yen |
| Release history | |
| Hexar (original AF black) | February 1992 |
| Hexar Gold (Classic) | March 1993 |
| Hexar Rhodium | May 1994 |
| Hexar Silver | April 1997 |
For the detailed story of the development of Hexar, see an article written by the engineering team (though it is written in Japanese). [1] The above figures and drawings were taken from this document.
Basic operation
This section was contributed by Philip Jackson.
Basic functions
Pressing the shutter release button halfway down and holding it sets focus and exposure. Avoid covering autoexposure and autofocus sensors. Autofocus is set on the spot within viewfinder central cross hairs; center weighted metering covers the area around the central cross hairs in A and P modes (15°), and central spot (4°) in M mode. Exposure readings are indicated by red + and - signs in viewfinder; green dot is focussing completion mark. Effective distance range is 0.6m to infinity. Flashing green dot indicates distances less than 0.6m. Frame moves to automatically compensate for parallax; distance scale appears as a break in diagonal line in top right hand corner. Infrared active autofocus system will not work through windows and may not work with some very small, dark, reflective or light-emitting objects. Use manual focus or focus lock to set by aiming the camera at another object of similar brightness at about the same distance.
P and A modes
P is the basic standard mode. Program changes shutter speed to try to match set aperture for proper exposure. If considered necessary, aperture will also be automatically changed. Under and overexposure warnings may appear. In aperture-priority (A) mode slow shutter speeds are selected without regard for the camera shake critical speed, although at lower speeds the red — led will blink slowly as a warning in the finder frame.
Manual mode
(1) Set main switch to M. (2) Press select button, then up-down buttons to specify shutter speed. (3) Set the aperture. Red + or - leds in viewfinder remain illuminated for 10 seconds after setting to allow exposure to be checked with 4° spotmeter. When both leds are illuminated setting is correct within 1/3 f value. To change setting while looking through viewfinder, (1) Press shutter release halfway to reilluminate leds. (2) Rotate aperture dial to adjust exposure setting. Alternatively, (1) Set main switch to M and select desired aperture. (2) Press shutter release halfway and hold to display correct shutter speed corresponding to previously selected aperture. (3) Press up-down buttons to set speed. Shutter speed may blink to indicate that the exposure exceeds display range (EV3-18), but camera will be properly controlled at the specified value.
Focus hold
(1) Place autofocus frame on subject (2) Press shutter release halfway and hold (3) Reframe and slowly press shutter release fully.
Fixed focus mode
Focus lock: (1) While half pressing shutter release (2) Press MF. (3) Reframe composition and fully depress shutter release. For focus lock with alternative exposure reading: (1) Half press and hold shutter release. (2) Press MF. (3) Release shutter and depress again with automatic exposure frame positioned to set correct exposure. (4) Reframe composition and fully depress shutter release. For Infinity lock: Press MF: "999" (infinity) will be fixed. Manual focus: (1) While pressing MF (2) set with up-down button. * Turn off to cancel. Depth-of-field scale roughly shows range at f/8.0 (white marks) and f/16.0 (full focus indicator window). Holding MF for more than one second recalls last manual setting. Zone focus or hyperfocal distance can be preset.
Hyperfocal distance
Aperture f 2 2.8 4.0 5.6 8 11 16 22 Manual setting m 20 20 10 7 5 3.5 2.4 1.7 Sharp to infinity m 10 10 5 3.5 2.5 1.75 1.2 0.85 (Rounded out from calculations for 35 mm lens with circle of diffusion of 0.033 mm; range should be reduced for more critical work or larger scale enlargements).
Exposure compensation
(1) Set main switch to P or A. (2) Press select button. (3) Change value with up-down button. Range is ± 2 EV in 1/3 stop increments. * Press select again to display frame counter; exposure compensation mark remains displayed. Turn off to cancel.
Film speed manual setting
(1) Set main switch to A. (2) Press select button and hold more than a second. ISO speed will be displayed. (3) Press up-down button to specify speed from 6 to 6400. Last two digits are abbreviated to H; e.g. 3200 = 32H. Film speed defaults to previous manual setting when a new non-DX film is loaded. To avoid manually resetting each new DX coded film, cover DX code with tape. Film speed, then frame number are displayed immediately after loading. (DX films automatically advance to first frame when camera is switched on after loading; depress shutter release to advance non-DX films.) To cancel manual setting, load a new DX film or reset.
Rewinding
R button starts early manual rewind. To stop automatic rewind (at end of roll) turn main switch off; then on again to resume. Pressing MF while turning on invokes silent rewind mode. If frame counter blinks and rewinding stops halfway, press shutter release halfway or rewind button to restore ordinary rewinding. Just before rewind is completed, motor pauses for a second, and [—], then [0] flashes. Open back or switch camera off at this point to retrieve film canister with film tip protruding, otherwise film will be completely rewound.
Silent mode
(1) Press and hold MF. (2) Turn on main switch. L is displayed in frame counter. * Turn off to cancel. To further reduce sound use fixed focus and manually preset aperture using A or M mode. Avoid switching camera off and on again. Film advance can be delayed by keeping shutter release pressed (release after pointing camera away from subject, place camera under cloth to muffle the noise, or wait until sound will be camouflaged by other ambient noise). Rewind may be delayed in silent mode—check frame counter to determine when last frame is exposed. Turn camera off and on again holding MF to resume rewind in silent mode. Silent mode may be cancelled with certain films or when battery voltage is low.
Time exposure
(1) Set main switch to M. (2) Press down button to set shutter speed to T. (3) Press shutter release to commence exposure. T appears on display panel for duration. (4) Press shutter release again to close shutter.
Multiple exposure mode
(1) While pressing self button (2) turn main switch on. Number of exposures taken appears in parentheses in display panel. Indicator only advances to 9, but the number of times a frame can be exposed without being advanced is unlimited. * To cancel and advance film, turn main switch off.
Self timer
Press self button to activate. Light comes on for seven seconds, blinks for last three. Focus and exposure are set when button is first depressed, so take care sensors are positioned on subject to ensure settings are correct. * Turn main switch off to cancel. If control over actual moment of exposure is not critical, self-timer can be used as a substitute for a cable release, or to start exposure on T setting.
Camera-shake critical speed
Initially set to 1/30 second; possible range is 1/4 to 1/60 second. (1) Set main switch to P. (2) Press Select for more than one second. [1/30L] appears in frame counter. (3) Change value with up-down buttons. * Reset to change setting. Default is restored when battery is replaced.
Automatic infrared focus correction mode
(1) Set main switch to A (2) Press select for 1 second (3) Press down button until "ISO—" appears (4) Press MF button to display wavelength values once for 750 (Konica) or twice for 850 (Kodak). Use M mode to set correct shutter and aperture values. * Setting is cancelled when roll is finished.
Flash
Full-Auto (P) mode
HX-14 dedicated flash is automatically activated when available light falls below threshold value. Correct exposure is determined by flash light metering system (Flashmatic). Flash is fired at full power, aperture is set according to autofocus distance to main subject, and shutter speed is automatically adjusted to balance background exposure and prevent it remaining dark. (1) Set main switch to P. (2) Set flash switch to P-FULL. When charging is completed, aperture will be set automatically and [FL] will appear on the display panel. Flash range is 0.6 to 7 metres at ISO 100 and 1.2 to 14 metres at ISO 400. Recycling time is 0.5 to 7 seconds. Camera or subject movement may be a problem in low light. Set wide aperture and increase camera shake critical speed to 1/60 second to more effectively avoid blur.
Auto (A-M) mode
Flash intensity varies with subject distance (a sensor extinguishes the flash when exposure is sufficient). (1) Set flash switch to A. (2) Set relevant aperture value for film speed (f4 for ISO 100 or f8 for ISO 400). Effective flash range is 0.6 to 3.5 metres. As slow shutter speeds may be selected in A mode regardless of camera shake critical speed, blur may be more likely than in P mode. Flash synch is rear curtain-type, meaning moving subjects may be blurred by the long exposure needed to adequately expose the background. This blur should appear 'behind' the sharp image captured by the flash, which fires just before shutter closes. Warning [—] blinks slowly in the finder frame when the shutter speed falls below the critical level. Use a tripod, or use M mode with faster shutter speeds to more effectively deal with subject movement. In M mode, flash will synch at any speed up to 1/250.
Manual (A-M) mode
Aperture is adjusted as necessary for subject distance and film sensitivity. (1) Set flash switch to P-FULL. (2) Calculate correct aperture with the formula F = GN/m (e.g. GN 14 (at ISO 100) divided by 2 metres equals f7 [or GN 28 (at ISO 400) ÷ 2m = f14]).
Manual guide number setting
To use an more powerful flash unit with P-mode Flashmatic functionality: (1) Press the select button while turning the main switch on. (2) While holding the select button down, press the up-down buttons until the desired flash guide number (P 1.0 - 64) appears in the display panel. If desired number does not match available settings, choose the next lowest setting (e.g. select 23 instead of 24). When setting is complete [PFL] appears. Turning main switch off cancels this mode, but the same guide number can be reset by holding down the select button when turning the main switch back on. To re-use dedicated flash, reset initial value [PN].
Flash units produced by other manufacturers may damage the camera circuits if they have a high voltage of over 200V passing through the synchro circuit. Multiple synchro contact points or broad-area contact points may also cause problems.
Battery
Timer automatically turns power off after two hours if camera is accidentally left switched on. Lithium 2CR5 battery should last for about 200 rolls of 24-exposure film. Flashing "bc" indicates low power; "bc" ceases flashing when battery is exhausted. Turn main switch off before replacing battery. Manually set camera-shake critical speed, ISO speed, etc., must then be reset.
Filters
Filter thread is 46 mm. Use exposure compensation or manual film speed setting to increase exposure by relevant filter factor. Lens performs best without skylight or UV filters; use only when absolutely necessary for protection. Some filters may impede lens movement at close focusing distances (0.6m.), causing an error [EEE] to appear in indicator panel. Remove filter, and reload batteries to clear the error. A filter shim (thin metal spacing ring) can be fitted if necessary.
Malfunction
If "EEE" appears on the indicator panel (indicating an error in the microchips), press the shutter release. Repeat if necessary. Next try removing and reloading battery. If the "EEE" display still does not disappear, the camera may need to be returned for repair. Functioning temperature range is -10° to +40°C; slow reaction in display panel may indicate low temperature; alternatively, continuous dark display may indicate high temperature. If no ISO value or frame number is displayed when film is loaded, press select button. If [0] is flashing, load film again or remove rewinded film. If [—] is continuously displayed, turn main switch to M then back to P.
Shutter release (erratic pre-focus) problem
The shutter button problem seems very common. The symptom is that the half-depression becomes erratic or intermittent and the camera can't pre-focus reliably. Sometimes, it doesn't pre-focus, sometimes it does pre-focus but it loses the focus shortly after, making recomposition almost impossible. In some other instances, the full-depression will not trip the shutter reliably. This is a very frustrating problem. The repair will requires (1) to disassemble the camera's top cover and a couple of other things, and to remove the shutter switch; (2) to disassemble the switch to clean the contacts; and (3) to put all parts back on. The switch is a double-action tactile switch made by Misaki Electronics (ミサキ電子工業, http://www.e-misaki.co.jp/).
Taking the top cover off
The following photographs, instructions and other information are for your information only. Use the information at your own risk. In general, this shouldn't be the first camera you work on. If you have plenty of repair experience with SLRs and rangefinder cameras, you shouldn't find this procedure difficult. It takes about one hour, including necessary breaks to take pictures :-)
The camera's top cover is held in place by 5 screws. Two screws are on the front side, hiding under the rubber grip pieces. One screw is on each side of the lens on the front side.
This picture shows the underneath of the top cover. This view can be obtained by taking the top cover off. Use all usual precautions in camera repair; remove battery (if you do operation check before reassembling, be very careful!), record the aperture and power/mode dials, and be very careful about fingreprints, scratches and fragile flexible boards. The hot shoe connection is soldered on fragile flexible board via short regular leads.
This picture is the closeup of the control dial PCB that sits atop the shutter release switch. (Note that the 3 screws that hold this PCB is slightly shorter than the 5 screws that hold the top cover.)
Get to the switch
The switch that needs to be replaced is shown slightly right of the center. It is a square, four-teminal tact switch that senses halfway and full depression of the shutter release button.
This is the bottom view of the tactile switch removed from above. Note that the two boss pins (the plastic pins off midline to uniquely determine the correct direction of the placement of the part) that go in to the holes shown in the third picture below. The two pins nearest to the bosses are the common contacts.
The tactile switch is held in place at two places of the metal cover (top right) along the sides without pins. Disengage them to open the switch, very carefully, not to lose the parts or to damage any of them. The contact failure was caused by the dirty contact, both on the base (lower left) part and the metal contact part (lower right). The picture above was taken before cleaning and so you can see the dirty contacts. Clean them in a suitable nonpolar solvent, such as hexane or Goof Off, which is a blend of a few nonpolar and slightly polar solvents, such as xylene and diethyleneglycol monomethyl ether. Electrical contact cleaner product may be used, but not the type that leaves oily film. The cleaned contacts should be absolutely dry.
When I took this camera apart, the halfway depression or focus lock position was almost completely inoperative, althought he full depression was working maybe twice every three pushes. However, I see almost no wearing of the mechanical contacts. The problem was surface oxidation or other chemical comtamination of the contacts. Even if the metal contacts were somewhat worn out, as you see in the picture, the part has two sets of contacts, so that the non-worn side could be used after thorough cleaning. This double action switch has considerably simpler structure and larger parts than any of the current double action tactile switches manufactured by Japanese or Taiwanese switch manufacturers, due to old bulky design!
Comparison of the Misaki tactile switch used in Hexar AF (left pieces) and the latest double action tactile switch SKRN-PA manufactured by ALPS (right). Each grid is 5x5 mm. Note that the Alps switch is much smaller and also much thinner. The Alps switch has better, firm tactile feeling of the half-pressed stage, and it is rated for 30 000 cycles. In the worst case when the Misaki switch completely dies, the Alps switch can be placed (glued) in the Misaki switch, with the contacts switably wired.
This is the flexible PCB after removing the tact switch discussed above, showing the wiring pattern. The left two contacts are common contacts, the right top is half-depression (momentary on), and the right bottom is full-depression (momentary on). Blow up the two pictures above and compare the connections of the contact until you get good sense out of this...
Putting the stuff back
When putting the cover back, make sure that the power/mode dial and aperture dial engage correctly. You can view the aperture diaphragm from the front of the lens, and you can tell when the dial is at f/2 position (when diaphragm opens up all the way). Also watch out for the hot shoe connection cords, which should be in the empty space behind the viewfinder system, not on top of it. Be patient and gentle to them.
Sticky buttons (usually MF, Select or both)
These tiny buttons may get sticky and they don't come out once pushed in. They are caused by worn out switches. The bad news is that I haven't found a good replacement part for them. The good news is that you have two spare parts in your camera: the rewind (R) button and self timer button. As you see in the pictures above, those buttons use the same switches internally. So you can unsolder switches from R, MF, Select and self, and then resolder the good ones for middle two places (select and MF) and put the bad ones to R and self.
Camera strap compatibility problem
Hexar AF cameras have strap loop that is narrow enough not to accept most camera straps. The easiest way is to buy a narrow nylon strip from craft stores (together with strong nylon thread and some needles) and make custom strap end attachment.
Domke 1" narrow camera strap
This strap is said to have woven nylon ends that are narrow enough to go through the loops of Hexar camera.
Ricoh GR Digital strap GS-1
This strap, with prominent GR Digital logo on it, can be attached to Hexar AF. The problem is the presence of the logo. It looks like this: http://www.ricoh.co.jp/dc/option/case/gs1.html
Links
Konica Hexar AF by Stephen Gandy
Konica Hexar AF review on Photo.net
資料室 性能表 Konica Hexar 外観写真かここのリンクから拝借しました。ありがとう。
要約
この記事では、ヘキサーＡＦ(ブラック)の仕様や設計に関する一般的な情報と、よくある問題点について解説しています。
特に、シャッターボタン不良の故障はよく発生し、典型的な症例としては、半押でのプリフォーカスが機能しなくなったり、不安定になり、一回プリフォーカスできてもすぐリセットされてしまうというものです。また、全押でシャッターが切れないという症状も起り得ます。この故障は、内部のタクトスイッチの接点不良によるものですが、接点そのものが摩耗してしまうことは稀で、金属接点表面の酸化あるいは化学汚染により接点不良になるもので、これは部品を基板から外し、スイッチを分解し、適切な有溶剤(ヘキサン、キシレン等)によって洗浄し、組み直すことにより解決できます。
また、Select や MF などのボタンがへこんで、入ったまま出て来なくなるという現象も頻発します。これはスイッチ自体の劣化によるもので、部品交換が原則ですが、交換部品の型名などはわかりません。しかし、上記写真を見てもわかるように、巻き戻し(R)とセルフタイマーのボタンも内部では同じスイッチを使っていますので、これを入れ替えてしまえば、とりあえず巻き戻しとセルフタイマーを使用しない限り、しばらくそのまま使えます。
その他の情報も随時追加していきます。
