Home
SearchSearch MemberlistMemberlist RegisterRegister ProfileProfile Log in to check your private messagesLog in to check your private messages Log inLog in

M42 Rikenon 1.4/55mm CONVEX rear, Tomioka but not COSINA ?
View previous topic :: View next topic  


PostPosted: Fri May 15, 2015 10:31 am    Post subject: M42 Rikenon 1.4/55mm CONVEX rear, Tomioka but not COSINA ? Reply with quote

This post is supplementary to topic: http://forum.mflenses.com/my-favourite-50mm-cosinon-55-1-4-t70916,start,45.html

I was thinking: did COSINA ever made M42 COSINON 1.4/55mm lens with convex rear? As far as i know the answer is negative.
So the only possible producer for slightly convex rear model should be Tomioka. What do you think?

Interesting especially in case of RICOH Rikenons. They exist in both 100% flat rear and slightly convex rear designs. The above could mean RICOH was supplied both by Tomioka and Cosina or Tomioka only.

Sadly this would mean full exception to the feet / meters positioning theory discovered by member Snowcat (Cosina made lenses have meters on their distance scale written above feet, while Tomioka wrote feet above meters). Explanation is easy though: Ricoh demanded compliance with its line look.

Holding in hands 100% flat rear Rikenon and slightly convex rear Rikenon: are they different in design and how?


PostPosted: Fri May 15, 2015 11:41 am    Post subject: Reply with quote

Are you talking about all-metal versions? There is also 3rd all-metal version with a flange around the rear element:


In addition there are 2 versions of coating of this lens: one usual amber/violet and one blue/magenta.
There is a matching Cosina lens:


There are also a rubber grip versions of Rikenon and Cosina that look identical.

In addition to Cosina with slightly convex rear element it would be nice to find a Cosina with the same plastic A/M switch as on Rikenons.


PostPosted: Fri May 15, 2015 11:47 am    Post subject: Reply with quote

..and the same looking Auto Revuenon 55/1.4 (silver inner front lens ring)


PostPosted: Fri May 15, 2015 8:39 pm    Post subject: Reply with quote

Hmm I have no idea if Cosina made such a lens ever... Mine is with completely flat bottom element. I asked two friends who usually have some information about old lenses and they both don't know also. They said "maybe they did, maybe they didn't".


PostPosted: Fri May 15, 2015 8:58 pm    Post subject: Reply with quote

As always, these threads are a waste of time because we have no idea of the myriad internecine agreements and partnerships that existed between the various Japanese optical factories.

We know that Cosina, Tomioka and Chinon all had factories in the same location in Nagano Prefecture; we know that they all made parts that they sold to other makers as well as making complete lenses.

Therefore it is a pointless exercise to try to work out exactly who made what.

Just go shoot the lens, see if it performs in a way you like and if so, use it, if not, sell it on.


PostPosted: Sat May 16, 2015 8:52 am    Post subject: Reply with quote

Fantastic photos here: http://forum.mflenses.com/ricoh-auto-rikenon-1-4-55-m42-t38517.html

To Dimitry and Snowcat: my proposition is to identify all Rikenon versions including the serial number. There is increasing chance one sees a mutant 1.4/55mm lens combined from different parts.
Labels, rear systems and more can be switched and this makes proper ID a tough job.

I have four all metal Rikenons starting serial 313, 315, 316, 318 all have slightly convex rear.

Could you check lower serials in your collection for flat rear? Like Matt's 101: http://mattsclassiccameras.com/rikenon_14_m42.html


PostPosted: Sat May 16, 2015 9:15 am    Post subject: Reply with quote

My AUTO Rikenon 55/1.4 is all metal,scalloped grip, SN:219xx, flat rear, silver ring near the mount


PostPosted: Sat May 16, 2015 10:42 am    Post subject: Reply with quote

Pancolart wrote:

To Dimitry and Snowcat: my proposition is to identify all Rikenon versions including the serial number.

I have only one Rikenon that is similar to the one I posted above but with blue/magenta coating. s/n 102XXX

Pancolart wrote:

Could you check lower serials in your collection for flat rear? Like Matt's 101: http://mattsclassiccameras.com/rikenon_14_m42.html

Matt's lens also can be similar to the one I posted above. I think really low serials should have 5 digits.

radissimo77 wrote:
My AUTO Rikenon 55/1.4 is all metal,scalloped grip, SN:219xx, flat rear, silver ring near the mount

Can you please post the pictures of your lens? Front, side with DOF marks and rear (with the lens set to infinity to fully expose its rear element and taken from the angle like in the last Cosina shot above).


PostPosted: Sat May 16, 2015 8:05 pm    Post subject: Reply with quote

I lost the overall reasoning, however I have a flat-bottom, Amber, 308xxx rikenon.


PostPosted: Sat May 16, 2015 8:36 pm    Post subject: Reply with quote

@ enzodm and radissimo77: for few years i was sure i have 100% flat bottom Rikenons. I've checked more then once but not careful enough.
Only after taking the ruler and putting it on the rear element holding lens in front of my eyes i saw the slight curvature. Please check carefully.


PostPosted: Sat May 16, 2015 9:42 pm    Post subject: Reply with quote

Actually you are spot on Pancolart, the rear is NOT completely flat, there is very slight curvature to it (much, much less than my Mamyia-Sekor 55/1.4 for example)




PostPosted: Sat May 16, 2015 11:13 pm    Post subject: Reply with quote

enzodm wrote:
I lost the overall reasoning, however I have a flat-bottom, Amber, 308xxx rikenon.


There is no overall reasoning, these threads just go round and round and achieve nothing but adding to the confusion.


PostPosted: Sun May 17, 2015 4:13 am    Post subject: Reply with quote

iangreenhalgh1 wrote:
enzodm wrote:
I lost the overall reasoning, however I have a flat-bottom, Amber, 308xxx rikenon.


There is no overall reasoning, these threads just go round and round and achieve nothing but adding to the confusion.


Sometimes it's fun to ride the roundabout;)

I have the "flat element" version. One of my favorite lenses. Just an all around good lens. On my APS-C it approximates an apparent 80mm FL. Sharp, fast, good colors, nice bokeh, well made, easy to use and inexpensive.


PostPosted: Sun May 17, 2015 5:03 am    Post subject: Reply with quote

jamaeolus wrote:
Sharp, fast, good colors, nice bokeh, well made, easy to use and inexpensive.


That's what matters! Who made it is very much a moot point when talking about the Nagano companies - Tomioka, Cosina, Chinon, it's all just guessing and quite unproductive. Smile


PostPosted: Sun May 17, 2015 6:22 pm    Post subject: Reply with quote

Mysterious and wonderful lens that always gets the job done. The Rikenon 55 is the only 1.4 I own now. The rear element on mine is slightly convex. Love these posts...

Last edited by Jeff Zen on Mon May 18, 2015 2:05 pm; edited 1 time in total


PostPosted: Sun May 17, 2015 8:12 pm    Post subject: Reply with quote

Ok, I checked and it is not truly flat.

Ian: most of what a collector does has no meaning for a non collector. Speculation around who built what can be part of the game... and on the web there is room for any depravation, including tomiokaphilia (or cosinophilia) Smile


PostPosted: Mon May 18, 2015 7:10 am    Post subject: Reply with quote

enzodm wrote:
Ok, I checked and it is not truly flat.


radissimo77 wrote:
Actually you are spot on Pancolart, the rear is NOT completely flat, there is very slight curvature to it...


This is getting more and more interesting. Authentic 1.4/55 M42 Rikenon that has 100% flat rear is yet to be found.


PostPosted: Mon Sep 07, 2015 9:25 pm    Post subject: Reply with quote

Pancolart wrote:
enzodm wrote:
Ok, I checked and it is not truly flat.


radissimo77 wrote:
Actually you are spot on Pancolart, the rear is NOT completely flat, there is very slight curvature to it...


This is getting more and more interesting. Authentic 1.4/55 M42 Rikenon that has 100% flat rear is yet to be found.

Just wanted to update this thread that such a lens was found http://forum.mflenses.com/auto-rikenon-55-f1-4-t72538.html. There is also an identical Sears version so it is safe to say it is not the single copy.


PostPosted: Mon Sep 07, 2015 11:49 pm    Post subject: Reply with quote

This is my copy of Auto Rikenon 55 f1.4 with flat rear element.





PostPosted: Thu Sep 10, 2015 11:24 am    Post subject: Reply with quote

Interesting. Quite low serial.


PostPosted: Sat Nov 28, 2015 6:05 pm    Post subject: Reply with quote

Mine looked flat to the naked (aging) eye, but I placed a flat business card on it, and sure enough, it has a very slight curve.

SN is 311642, consistent with the series mentioned above.

Regardless, it is has become one of my favorite 50-55mm lenses. I use it often with consistently great results.


PostPosted: Sun Nov 29, 2015 12:14 am    Post subject: Reply with quote

Can anyone tell me which on is better wide open,some say that the 55mm f1.4 is very good and some say that they are soft and glowing wide open.I want to try one and what I read Sears seems to be good ones.Price has risen and is it really better then the Takumar 50


PostPosted: Sun Nov 29, 2015 12:22 am    Post subject: Reply with quote

They vary a lot, QC wasn't the strong point. I had one that was pretty poor, others have had really nice ones.

A much safer purchase would be something like a Minolta MD 1.4/50 which is a better lens and has far less variation between copies.


PostPosted: Sun Nov 29, 2015 7:44 am    Post subject: Reply with quote

I found my two copies of (EDIT) Mamiya/Sekor AUTO 55 f/1.4, which are likely the same lens as the Rikenon and Sears, to be very sharp at the center wide open.
And thought it bettered the Super Takumar 50 f/1.4, SMC Takumar 50 f/1.4 and my copy of a MD Rokkor-X 50 f/1.4 w/ the 55mm filter thread.
My Minolta is more mechanically worn than the others and could account for its wide open softness. Also had more coma.

(Corrected my post, must be getting senile.)


Last edited by WNG555 on Sun Nov 29, 2015 9:06 am; edited 1 time in total


PostPosted: Sun Nov 29, 2015 7:55 am    Post subject: Reply with quote

Zeeke wrote:
Can anyone tell me which on is better wide open,some say that the 55mm f1.4 is very good and some say that they are soft and glowing wide open.I want to try one and what I read Sears seems to be good ones.Price has risen and is it really better then the Takumar 50


none of my 55/50 1.4 are sharp WO ( Cosinon, Rokkor MC, Rokkor MD, Pentax M) . As mentionned before, they might be copy variations . So I have to admit that I have been unlucky. I use the MC and the Pentax stopped down at f2. Both are great lens.
In term of focusing and dof , 1.4 is difficult to master anyway. I stopped looking for a 50 1.4 sharp WO.

My sharpest 50 mm WO are the Rollei Planar f1.8 and the Minolta MD (III) f2. The latest is not as sharp and contrasty but the homigeneity across the frame (FF) is very good at this aperture . So it is very usable if you care about composition.This Minolta is cheap and common ; it is overlooked.