Mamiya Auto Sekor 55mm f1.4

ramiller500 · Posted: Fri May 04, 2012 5:25 pm Post subject:

I don't have my lens handy, but recall that the center of the rear element seemed to extend a little beyond the element's outer retaining ring. There is no big rear element housing such as those I have seen with some Yashinon DX lenses.

ilguercio · Posted: Sat May 05, 2012 9:20 pm Post subject:

Wide open, with the external flash pointed towards the ceiling.

Crop:

Lovely.

ramiller500 · Posted: Mon May 07, 2012 11:54 am Post subject:

Correction---I rechecked my all-black Mamiya Sekor 55mm/1.4 lens (serial number 120585) carefully from the side, and the rear surface of its rear element really is flat, not slightly convex as I had thought! This result agrees with the statement above that this lens had only the flat variant. Sorry for the confusion.

ilguercio · Posted: Mon May 07, 2012 12:01 pm Post subject:

Cool, so the silver ones were probably built up to a certain s/n and then it was taken over by the all black version.
My copy is #134067, so it's consistent with your lens.
Wink

Ilias83 · Joined: 22 May 2012 Posts: 35

I have both Silver/Black and Black 55mm 1.4.
I decided to keep the Black one as I noticed that the Silver reflected light
from chrome nose to glass when I was trying to use it without hood.
I wish I could keep them both but I cannot afford owning every les twice so I decided to have them all black.

First of all some pictures of the lenses on a black and a silver/black 1000DTL

So I start with samples from Silver lens

I used an adapter to fit it on a Canon 40D:
f/1.4

f/2

f/2.8

f/4

My Black lens is in almost perfect condition:

And here are some more pictures shoot with Black lens on an Olympus E-P1 using an adapter.

f/1.4

f/2

f/4

f/5.6

f/8

f/1.4

f/2

f/2.8

f/4

f/5.6

If you click on images you can see them bigger on external link.

dimitrygo · Joined: 01 Apr 2009 Posts: 561

Pancolart · Expire: 2013-11-18

Ilias83 · Joined: 22 May 2012 Posts: 35

dimitrygo · Joined: 01 Apr 2009 Posts: 561

dimitrygo · Joined: 01 Apr 2009 Posts: 561

JBruja · Posted: Sat Jun 02, 2012 9:02 pm Post subject: Convex Rear End

My Mamiya-Sekor (no. 15263)(55mm f.14) is the black version with a well worn exterior - however - the glass is perfect. The rear element is slightly convex on my version and is slightly radioactive at 377 micro roentgens/hr - no biggie. The front elements on at least 1 of my other lenses has about the same reading. Fluorite comes to mind as a source. Anyway here is a photo I took on the fly this am.

Ilias83 · Joined: 22 May 2012 Posts: 35

One more picture shot with black lens on my black 1000DTL.
Film used was a Fuji S-400 and aperture was set on 1.4

sshanky · Joined: 25 Dec 2013 Posts: 2

Hi, I have two copies of the 55mm f/1.4 mamiya sekor, but one of them has a thick mount that prevents focusing on anything other than very close things (it moves the lens about a centimeter too far from the camera):

Here are the two lenses side by side:

Obviously the right-hand lens is the one I am confused by. The one on the left works fine.

Here they are again. the right hand lens is the one with the thick mount:

Any ideas? It must be for some other format?

thanks!

fermy · Joined: 17 Feb 2012 Posts: 1974

sshanky · Joined: 25 Dec 2013 Posts: 2

I tried removing it. Underneath is the aperture mechanism, loose. No way to mount at that point.

luisalegria · Expire: 2018-01-18

The second lens was improperly reassembled.

eno789 · Joined: 27 Aug 2010 Posts: 159 Location: California

Some autumn leaves taken with this lens:

A few more in the Flickr set

memetph · Joined: 01 Dec 2013 Posts: 940 Location: Poland

This lens is supposed to be Tomioka. I have the same branded Cosinon . 55mm 1.4 with the flat rearlens and the same build.
Nice lens . I like it very much

dimitrygo · Joined: 01 Apr 2009 Posts: 561

memetph · Joined: 01 Dec 2013 Posts: 940 Location: Poland

If it is the case, which is another speculation, it is a very precise copy.
Same size, same aperture,same rings position, even the screws are at the same place , same flat rearlens.
Those lenses are similar to the very small details.

dimitrygo · Joined: 01 Apr 2009 Posts: 561

memetph · Joined: 01 Dec 2013 Posts: 940 Location: Poland

You are right. It is very difficult to know which lenses were produced by Tomioka . That is why I wrote , "this lens is supposed....."
I will investigate about Cosinon and their own production of lenses.I remember Cosina as a famous moviecameras producer (super Cool

.At my time there were not very famous as photo camera producer.

cropshy · Joined: 12 Oct 2013 Posts: 12 Location: Virginia, USA

Does anyone know if the Mamiya/Sekor 55mm f1.4 is the same as the Rikenon 55mm f1.4 with the Nikon mount?

Pancolart · Expire: 2013-11-18