Chinon CE II Memotron (1976)

memotron1What is it?

This is a Chinon CE II Memotron 35mm SLR camera from 1976.  This model was one of the very last 35mm cameras released by any company to still use the aging M42 screw mount.  It’s headline feature was that it was capable of open aperture auto exposure using almost any M42 screw mount lens.  Other companies like Yashica and Pentax had released their own models which supported open aperture auto exposure, but they were limited to open aperture metering to specific lenses.  Without a compatible lens, the camera could only meter when the lens was manually stopped down.  This model, along with its predecessor and successor, are to my knowledge, the only cameras ever made that could meter wide open using the M42 screw mount.  This feature alone made this camera relevant in the market as it offered one last hurrah for photographers with a large collection of M42 glass who wanted auto exposure without having to start over with an all new lens mount.

Film Type: 135 (35mm)
Lens Mount: M42 Screw Mount
Lenses: Auto Chinon 55mm f/1.7 coated + any other M42 lens
Focus: Fixed SLR Prism
Shutter: Focal Plane Vertical Metal Blade
Speeds (Electronic): 2 – 1/2000 seconds, stepless
Speeds (Mechanical): B, 1 – 1/2000 seconds
Exposure Meter: Dual CdS TTL Center Weighted meters
Battery: PX28 6v Silver-Oxide or Alkaline equivalent
Flash Mount: Hotshoe + dual PC M X sockets


chinonmanualChinon is a name not often associated with collectible cameras.  For those active in the 1970s, you probably remember them as a maker of discount screw mount and Pentax K-mount SLRs.  Their cameras were actually well built, but they weren’t exactly a company known for innovation.  In fact, many Chinon made cameras were rebadged and sold under the brand names of other manufacturers such as Argus, GAF/AGFA, Revue, Sears, Alpa, and Albinar.  As a result, there are far more Chinon made cameras out there than most people probably realize.

The company was originally formed by Chino Hiroshi in September 1948 as Sanshin Seisakusho in Tokyo, Japan.  Unlike other Japanese optical companies of the time, Chinon seemed to be in the business of making parts for other optics companies.  As best as I can tell, in the 1950s, they made camera lens frames and lens barrels for a variety of companies.  It doesn’t look like Chinon had any of their own optical products until 1958 at which time they released their first 8mm motion picture camera lens.

The company would change it’s name in 1962 to Sanshin Optics Industrial Co. Ltd, and then once again in 1973 to Chinon Industries Inc.  As best as I can tell, the company’s first 35mm camera was made in either 1971 or 1972, and I believe it was the Chinon M-1, a rather basic mechanical SLR with an M42 lens mount.

Finding a comprehensive history of Chinon and their early products has proven to be a bit of a challenge, so I’ll just skip to the point where Chinon decided that perhaps it was time for them to make some kind of innovative contribution to the camera industry.


The shutter release button is unnaturally tall, which is a side effect of how the auto exposure system works.

In 1974, Chinon would release the Chinon CE Memotron.  It was a well built camera with an excellent metal blade focal plane shutter capable of speeds from 2 to 1/2000 sec.  It was Chinon’s first camera capable of auto exposure, but how they accomplished it with the M42 mount was slightly different than what anyone else had done.

Its worth noting that by 1974, most of the industry had moved away from screw mount lenses.  Originally designed by Zeiss-Ikon prior to World War II, the first M42 cameras did not become available until the Contax S in 1949.  The benefit of a screw mount lens is in it’s simplicity.  The lens flange on the camera and the lens itself has a simple threaded screw pitch which mates the camera and lens together.  The M42 screw mount was used by many manufacturers throughout the 50s and 60s like Praktica, Asahi Pentax, Yashica, Petri, KMZ, Fuji, and eventually Chinon.

As cameras became more advanced, the need for a camera body to “communicate” with it’s lens became more and more necessary, especially when it came to automatic exposure as the camera would need to know which aperture was selected on the lens.  As a result, bayonet or breech lock lenses started to become common with most manufacturers because the lens was always in the same orientation at all times while mounted.

A few workarounds were created for the screw mount, the first of which which was a “stop down” pin that would be activated by a sliding bar located beneath the mirror in the mirror box of the camera.  This would allow a photographer to compose an image at maximum aperture regardless of what was selected on the lens, and then upon pressing the shutter release, the bar would push the pin, which would cause the lens to stop down to the selected aperture moments before the shutter would fire.  This was fine for manual exposure calculation because the photographer had ultimate control over shutter speed, but it posed a problem for auto exposure sensors since the camera wouldn’t know what aperture was selected until moments before the shutter fires.  There had to be a way for the exposure meter in the camera to know what aperture was selected on the lens before pressing the shutter release.

A couple of companies like Yashica and Asahi Pentax attempted to overcome this issue by creating new lenses that had a second pin on the lens flange that would indicate which aperture was selected.  The camera would be able to detect the selected aperture on the lens by sensing where this pin was and then automatically select an appropriate shutter speed based on the amount of light that was detected by the meter.  This worked quite well, except that it required special lenses with this second pin.

Edit 12/1/2016: After posting this review, I was corrected that the Yashica Electro AX SLR was capable of open aperture auto exposure without a special M42 lens mount.  The Electro AX had an awkward auto exposure system that would always stop down the lens any time the shutter was cocked.  In order to compose your image wide open, you had to press and hold an override button on the front of the camera and release it before firing the shutter.  Also, due to changes in the reflex mirror, the Electro AX was incompatible with some M42 lenses, including several of Yashica’s own Yashinon-DX lenses which were popular at the time.  So while the Electro AX did have aperture priority AE capability without a special M42 lens mount, it’s implementation was awkward and certainly not as simple as that of the Memotron.

An SMC Takumar with the additional coupling pin next to a "regular" Takumar without it.

An SMC Takumar with the additional coupling pin next to a “regular” Takumar without it.

Look at the picture to the left of an Asahi SMC Takumar side by side with a “regular” Takumar.  The SMC Takumar was designed specifically for the Pentax ES and ES II which also had an AE system.  The sliding pin needed for open aperture auto exposure on the ES is in the foreground of the lens on the left.  Also on the SMC is a square metal stop on the outer ridge of the M42 mount.  This acts as a firm stopping point so that the lens cannot be “overscrewed” onto the camera.  This is required to assure that the sliding pin is always in the exact right position.  All of these changes needed to be made to these lenses to allow for the AE system to work properly.

If you tried to mount an existing M42 lens without these new features, the camera would have no way of knowing which aperture was selected.  In those cases, the auto exposure system could still be used, but only by manually stopping down the lens first.  This would not only darken the viewfinder and make composition more difficult, but would also slow down the process of making a photo, thus defeating one of the primary goals of an auto exposure system.

Chinon tried a different approach that was actually simpler than either Yashica or Asahi’s methods, but also had the benefit that it would work on any M42 lens, as long as it had the auto stop down pin which by 1974 was extremely common.  How it would work is that with a half press of the shutter release button, the auto stop down pin would become engaged at which time the meter would be turned on and take a reading a split second before firing the shutter.  If you just wanted to see the selected reading, you merely had to half press the shutter release and hold it.  Half pressing the shutter release also illuminates a green light beneath the viewfinder which acts as a “meter ready” indicator.  When the light is on, the camera has sufficient power to enable the meter.  If this light does not illuminate, you should replace the battery.


The green light beneath the viewfinder acts as a sort of readiness indicator. If it does not light up, then the meter isn’t powered on meaning the battery is likely dead.

Modern cameras can auto focus on an image with a half press of a shutter release, and although this wasn’t an auto focus camera, this had to have been one of the earliest examples of a camera that would perform some function with a half press of the shutter release.

But wait, there’s more!  Chinon had another trick up their sleeve which was the “Memotron” feature.  Upon half pressing the shutter release, the camera would retain it’s detected exposure settings and hold it.  This was useful if you wanted to expose for a different part of a scene and then hold the exposure settings and recompose the image.  This would have helped on brightly backlit or front lit scenes where the camera might not get the exposure correct.

Other than not requiring a special lens, the biggest advantage of this system is that if all you wanted was an aperture priority auto exposure camera, you would set your desired aperture, compose your image with the lens wide open, and then press the shutter release all the way down and the camera would do the rest for you.  There was no additional step to manually stop down the lens first.  While all of this sounds terrific, it had the side effect of requiring that the shutter release be taller and have a longer travel to allow for all of the things that needed to happen during it’s travel.  As a result, the CE II Memotron has the longest travel of any shutter release on any SLR I’ve used.


An ad for the CE-II Memotron highlights the cameras ability to auto expose with existing M42 lenses.

Chinon wisely used this feature in their advertisements for the Memotron saying that you could have an automatic electronic camera using the lenses you already own.  I could not find any information regarding production numbers of the Memotron series, but it had to have been at least somewhat successful as Chinon would make 3 different revisions of the CE Memotron all with an M42 mount.

The first CE Memotron was released in 1974 and then in 1976, the CE II Memotron was released which was essentially the same camera, except it had a new battery compartment, a provision for double exposures, and a shutter curtain blind to block light from entering the viewfinder for long exposures.  Otherwise the two cameras were nearly the same.

In 1977 came the CE-3 Memotron.  Still using the M42 mount, the CE-3 Memotron was a significantly different camera.  For one, it had a much smaller and lighter weight body.  This was in keeping with the trend of more compact and more portable SLRs like the Canon AE-1 and Nikon FM/FE.  The CE-3 lost the top 1/2000 second top speed and could only go as fast as 1/1000 second but it extended its slow speed to a max of 4 seconds, instead of 2 like on the earlier models.  Other changes to the CE-3 Memotron was a switch to two S76 silver-oxide batteries and support for an accessory power winder.


Although the CE II’s marquee feature was it’s auto exposure, Chinon didn’t skimp on the shutter, with a top speed of 1/2000 sec and a vertically traveling metal blade, it was pretty good.

The M42 Memotrons definitely extended the life span of the M42 mount and allowed photographers with a large collection of lenses to use them in a more modern way, but by the end of the 1970s, the decision was made to finally abandon the screw mount.  In 1979, Chinon would release the CE-4 Memotron using the Pentax K-mount.  From this point forward, all future Chinon cameras would use the K-mount, and the era of the M42 screw mount would officially be over.

Today, the Chinon Memotrons seem to largely go unnoticed in the used market.  I think the biggest reason for this is the relative insignificance of the entire Chinon brand.  Other than the Memotron, Chinon’s biggest contribution came by making cameras that were rebranded for someone else.  Their products were actually pretty well built, and in the case of the Memotron series, had some ingenious features.  Nevertheless, these cameras don’t often show up for sale very often, and when they do, they often don’t go for much.

My Thoughts

One of my favorite classic cameras is my Asahi Pentax Sv.  Its an extremely well built and compact SLR with excellent ergonomics, and it pairs with Asahi Super Takumar lenses, which are some of the best SLR lenses made with any mount by any company.  I love my Super Takumars so much, that I bought an M42 -> Nikon F mount adapter and use them regularly on my Nikon D7000 DSLR.  Many of the glamour shots used for reviews on this site were taken with a Super Takumar because of their excellent sharpness, color rendition, and ease of manual focus.

As I explored what other cameras I could use my M42 lenses with, I discovered Yashica’s M42 SLRs like the TL-Super, and the TL Electro X.  With those cameras came more excellent M42 Yashinon lenses to my collection.

Soon, I found myself with a library of some truly spectacular screw mount lenses, and as much as I loved the cameras they were intended for, I wondered what an auto exposure camera could do with them, and thus began my search for a model capable of auto exposure.  First came the Pentax ES II which I reviewed on this site.  I had some issues with that camera, namely with the meter which allowed me to shoot the camera manually fine, but the auto exposure system wasn’t reliable.  Since many ES IIs rarely sell for the bargain prices that I usually look for, I had a hard time finding one that I wanted to pull the trigger on.


Chinon made decent stuff, the CE II was a good camera, and it’s lenses were on par with other makes of the era.

Then one day, I received a private message from fellow collector, Mike Novak, and he alerted me to a Chinon CE II Memotron with Chinon f/1.7 lens on eBay with a mysterious Buy It Now price of only $10.  The camera looked pretty good, and thinking it was a mistake, I bought it.

When the camera arrived, I was pleased to see that it seemed to be in good working condition, but it had some condition issues.  For one, the leatherette body covering on top of the prism was missing.  Also, the viewfinder had quite a bit of dirt and possibly some desilvering inside of the prism.  Nothing that seemed to affect normal use of the camera, and for the price, I shouldn’t complain, but I was a bit disappointed that the camera wasn’t in better shape.

Like I do with every pre-80s vintage SLR, I replaced the foam light seals in the film compartment on the hinge, wiped the body down, loaded in some film and went shooting.  I had some family visiting from out of town, and we were headed to the Indiana Dunes on a Saturday, and knowing that a sandy beach is the absolute worst place you could take any camera, I decided that if I was going to bring something, it should be something with relatively low risk, so I loaded up the Chinon and took it with me.


All of the controls are exactly where you’d expect them to be. The little switch to the left of the viewfinder is a rear viewfinder blind.

Shooting with the camera was a mixture of good and just OK.  The good is that the camera feels solid and it’s ergonomics are about what you’d expect of a mid 1970s SLR.  All controls are in a logical location, and the viewfinder is large and bright.  A big plus to the Chinon compared to the Pentax ES II is that auto exposure works with “regular” M42 lenses without having to reach for a manual meter switch.


The shutter release on the CE II is quite tall and has a longer travel than any other SLR I’ve used.

On the negative side, the Chinon’s shutter release is taller than any other SLR I’ve ever used, and it has a very long throw.  I mention the reason for this earlier in this article, and it’s certainly not a deal breaker, but it is something that takes a little bit to get used to.

Although the viewfinder is large and bright, it’s only focus aide is a microprism dot in the center.  There is no rangefinder aide which had become quite common by the mid 1970s.  I can forgive this omission on earlier SLRs, but you’d think that this should have been standard fare by the time the CE II hit the market.


Its hard to see here, but there is only a microprism dot in the center.  It is nice to see the selected shutter speed from 2 sec – 1/2000 sec in the viewfinder.

The camera is also not lightweight.  Using an SMC Takumar 50mm f/1.4 lens, the Chinon weighs a hefty 1012 grams, topping the ES II with the same lens at 937 grams.  This might not seem like much, but if you prefer an M42 all manual experience, you could carry around the Pentax Sv which is a relative featherweight, weighing only 862 grams using the exact same lens as the other two.

None of this adds up to a terrible shooting experience, but since the reason for owning this camera was it’s auto exposure mode, it better do a good job if a user is to overlook these shortcomings.

My Results

My goal when shooting with this camera the first time was to test how useful an auto exposure mode could be on a screw mount camera.  Surely, the Chinon CE II Memotron was pushing the boundaries of what could be done with an M42 camera, but what kind of compromises would there be?  If I was an advanced amateur photographer in 1976 with a large selection of screw mount lenses, and wanted to try out auto exposure, but didn’t want to invest in an all new bayonet mount, was this camera worth a purchase?

Assuming that the Chinon 55/1.7 lens would give me at least decent results, I took the camera to the beach and exposed it to high contrast scenes with lots of movement, in an attempt to test how useful Auto Exposure might have been.

It’s worth a comment that I completely realize taking any sort of precision instrument to the beach is a terrible idea, and not one I would normally expose a valuable camera to.  While the Chinon CE II might have been a mid-level camera when it was new, it only cost me $10, so I was willing to risk exposing it to sand, and even carrying it with me into Lake Michigan for some shoreline shots.

Before I comment on the exposure meter, I have to say that the Chinon lens exceeded my expectations in sharpness, clarity, and color rendition.  I already hold my selection of Asahi Super Takumar screw mount lenses in very high regard, but I don’t know that I would be able to tell the difference between this Chinon lens and any of those lenses.  In fact, I wouldn’t be surprised if this lens is a clone of the designs used by someone else.  I have found no proof to support or dispel that theory, but whatever is going on inside that lens, is purely magical.

In terms of the auto exposure capability, I can honestly say Chinon’s magic goes beyond the lens.  In the very first image of the gallery above, I intentionally took a picture of a child in front of a backlit window to try and trick the meter, yet neither the yard outside of the window is blown out, and there is still sufficient shadow detail in the foreground to have a usable image.  I am not convinced that a modern DSLR could have done any better.

For the rest of the shots, while most of them were shot on a bright and sunny day, there was constant fast motion in nearly every shot.  Many AE systems can be fooled by high contrast images, rendering blown out highlights or murky shadows yet that didn’t happen here.  I used Fuji 200 film for this roll and I’ve seen that film’s limits reached on other cameras like the Fujinon 35-ML but in the Chinon, the images all came out with perfect exposure without any of the maladies that can often plague lesser AE systems.


The Chinon CE-3 resolves 2 of my 3 nitpicks of the CE II, a more compact and lighter weight body, and a split image rangefinder.

If I had to come up with some way that this camera could have been improved, it would have been to put it in a more compact design (like the later CE-3 Memotron), and figured out a way to not have the shutter release so tall.  I would have also preferred a split image focus aid in the viewfinder, but based on the perfect focus in every image on my test roll, I clearly didn’t need it.

The fact that a little known company like Chinon was able to implement a working AE system using nearly ANY screw mount lens in 1976 when nearly everyone else had moved onto more capable bayonet mount lenses, and do it with near perfection is damned impressive.  Yashica and Pentax tried, but even they couldn’t get it right.

I cannot understand how Chinon didn’t have more success as their engineers were clearly talented.  I don’t know if it was over saturation of the market, or if there was some type of corporate mismanagement, but whatever the reason, this is possibly one of the most impressive results I’ve seen from any camera made by a company more known for selling rebadged cameras under other names, than their own designs.

My Final Word

How these ratings work
The Chinon CE II Memotron is a very unique camera in that it allows aperture priority auto exposure using any screw mount lens with an auto stop down pin.  This means that you can meter wide open using any lens made by Asahi, Yashica, Praktica, Zeiss, or any other manufacturer.  If that wasn’t enough, the AE system is surprisingly accurate and works just as well as the systems in use by any other camera maker.  It is a well built and sturdy camera with a vertically traveling metal blade shutter with a top shutter speed of 1/2000 seconds.  This camera was designed to prolong the usefulness of M42 lenses, and it still serves that purpose today.  These cameras aren’t exactly common, but if you have an opportunity to pick one of these up in working condition, I absolutely recommend it!
Images Handling Features Viewfinder Feel & Beauty History Age
2 1 2 2 1 2 0%
Bonus +1 for being the only screw mount camera series to do AE correctly without needing proprietary lenses
Final Score 11.0

Additional Resources

One Comment

  1. I can’t lie – had I seen this camera sitting in case along a bunch of Chinon, Ricoh, Fujica, and other similar 70’s “second tier” SLR cameras, I’d have had no clue of just what a special little beast that it is. I’d have ignorantly dismissed it as a knock off of unknown mount that I wouldn’t get any takeaway from. Instead, you’ve enlightened me to realize that there are some real gems out there with otherwise overlooked names that are well worthy of consideration in the future! Well played Sir!

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