The User's Review: Auto Chinon Multi-Coated 50 mm f1.7, One of the Early AF Prime Lenses

This is a totally standing-alone AF lens although it was released as a Chinon lens. Its AF sensing and driving systems are located in the front of the K mount and without any AF control across the mount, making it an universal AF lens for all K-mount manual and AF SLR and DSLR bodies, theoretically. However, this AF lens can not be mounted on a body with a projecting eaves above the lens mount (e.g., Pentax K-x DSLR) because the eaves and lens case around the mount block mounting.   

It looks funny, strange, or professional?

Once installed, press this green button to go for AF. Its AF speed is acceptable although not as fast as the modern AF systems.

The focusing can also be set manually.

The green LED and a beep tell you 'in-focus'. The green light also falls down to the aperture size marked on the aperture ring that is shown in the v-shape opening above the lens mount. The lighten aperture size can be pick up by a aperture window on camera such as Pentax KX in order to display in the camera's viewfinder. A great design. There is another set of aperture size marks (on the left in the image above) for reading from the lens body directly.

It's manual are in multiple languages. The section in English is posted here.

The case and barrels of Chinon Auto Focus 50 mm 1.7 are made of plastic. I do not open it to look, but will put a question mark behind its durability.

35.60

The User's Review: Auto Chinon Zoom MC 35 - 70 mm, f3.3 - 4.5, One of the Early Self-AF Zoom Lenses

Funny, strange and professional looking, besides these, this AF zoom lens is more user friendly and can be mounted on more cameras because of the left-out aperture ring design, giving enough room for mounting. 

It's possible to AF,  MF, zoom or set the aperture ring,
using my left hand alone.

The lens length do not change when zooming,
but the front element and filter turn while focusing.

The aperture ring is out of the AF case,
providing more room for lens mounting.

Two switches, one for power and the other for beeping

The three pins stand in one line, matching the pattern of the contacts on Chinon CE-5. However, on other Chinon camera bodies such as the DP-5, the three contacts arrange in a different pattern. Wondering if Chinon produced other AF lenses to match the DP-5 and other models?

The focus ring with two rows of rubber teeth is wider,
easier to grip and turn

The barrels are made of metal and the AF system case is
plastic. I believe that many parts inside are plastic too.

The space between the mount and AF system case
makes it possible to mount on my K-x

An image of LED screen

An image at 70 mm and f4.5 under room light

An image at 30 mm and f3.3 under room light

An image of room light at 70 mm f4.5

50.98

The User's Review: Minolta Hi-Matic S2

This camera caught my eyes by the blue light coming from the distance window above the lens when the flash is released and the green light from the flash-ready lamp left to the finder eyepiece. The blue and green light make the camera look cool.

This manual focus camera is well built, with a light sensor under the lens front element and within the filter thread. Therefore, no light compensation is needed after a filter is installed. The flash and light meter are powered by 2 AA batteries. The exposure is automatic. The shutter will not fire without power. The focus distance is indicated by a needle and five scale symbols on the left of finder although both m and ft are shown in the distance window above the lens. No self timer and shutter release socket, but beeps in low light and out of flash range.

Here is the manual scanned in pic file:

The User's Review: Sears Auto 2X Tele Converter 4E/MC KR 271.8100 and a Review on Tele Adapters for K Mount

I got this Sears tele converter because of its 7 contact pins on the mounts. The six pins in one group are for Pentax K-A and K-AF mounts. Without any settings in a DSLR body, this converter can be easily used with Pentax KA or AF lenses.

The separate pin is a Ricoh P pin found on the mount of Ricoh XR-P, XR-20P and XR-30P 35 mm film cameras. On the camera side of the converter, this P pin is bigger and more flat on its top, therefore, is safe to mount on a Pentax AF body without jamming the converter.

I saw many tele-converters with different numbers of contact pins and listed them in the table. I know there are more out there. What I do not know is if there is any converter only with the Pentax A pin since it's the only one on my Pentax-A lens.

Brand	Model	Pin Number
Albinar	ADG Auto 2X Tele-Converter KR 857	7*
Consul	Auto Tele Converter 3X For Pentax-K	No pin
Deitz	2X Tele Converter MC-4	No pin
Gemini	Auto 2X Tele-Coverter	No pin
Komura	Telemore95 II 7•K•M•C	No pin
Pentax	Rear Conver-A 2X-S (47497)	6
	Rear Conver K T6-2X	No pin
Promaster	Spectrum 7 Auto Tele Converter MC7	7*
	Tele Converter MC 2X	No pin
Sears	Auto 2X Tele Converter 4E/MC KR 271.8100	7*
	Auto 2X Tele Converter 4E/MC 271.8102	No pin
Seikanon	Multi-Power Auto 2X For PK	No pin
Star-D	2X MC-4 Auto Tele-Converter	No pin
	MC Auto Tele Converter 2X	No pin
Takumar	Takumar-A 2X Tele-Converter	6
Vivitar	MC Tele Converter 2X PK-A/R-PK	7*
	Tele Converter 2X-22	No pin
	Tele Converter MC 2X TC	No pin

*including the six Pentax and one Ricoh P pins

The last thing I like to discuss here is the Ricoh P mount. I see various acronyms for this mount, including KR, R-K and R-PK. Although the P pin has the similar function as the Pentax A pin, they are located in two separate sites on the mounts. In most cases, they are well compatible, except mounting a P lens or adapter onto a Pentax AF body. Depending on the shape and length of the P pin, it may be trapped in the hole of auto focus shaft and jams the lens on the AF body.   

CPC 2X Tele-Converter MC KAR, 7 pins
Kalimar 2X Tele Converter KAR, 7 pins
ProSpec Auto 2X Tele-Converter 624-4349, 7 pins.
Tokina EL 2X Converter For P/KA, 7 pins (this one is more similar to Kalimar 2X 7pins)
Toyo Optic MC Auto Tele Converter 2X For PK, no pin.

15.99

The User's Review: Kalimar MC Auto Zoom 1:3.5 28 - 70 mm with a KR Mount, Released in the Mid 1980s

Many people know the Pentax KA mount with the 'A' gear on the lens diaphragm ring. Some people know the Ricoh P mount having the 'P' gear on the aperture ring. However, a few people know the Kalimar  KR mount marked both 'A' and 'P' on the ring.  'A' and 'P' are different from each other by differently locating a aperture pin on the mount that communicate the aperture between the lens and body. Besides the difference in the pins, sometimes it's difficult to take off a P-mount lens from a KA auto focus SLR and DSLR cameras because the P pin will be trapped the AF coupler on the body mount and jams the lens to be locked or turned off as shown in the Hin's page. In other words, it's better not to use a P mount lens on a AF K mount body.

With a smaller and tractable P pin, Kalimar KR mount lens still has such problem. Therefore use it only on manual focus bodies.

This Kalimar zoom lens was well built in (S.) Korea although the barrels and rings are plastic. It has a macro function with 0.4 m and 1:4 at the 70-mm end. Its filter size is 55 mm. The lens length will reach its shortest when the zoom/focusing ring sets around 40 mm/infinite. Its internal/front barrel will turn when focusing.