Why no love for Mamiya Sekor?

**ramseybuckeye** · 09-25-2010, 12:03 PM

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Originally posted by Ira

I just bought this lens, but it won't mount. Seems I have to grind down the perimeter near the mount.

Did you do this too?

Ira, I'm no expert, but I had an SX 21mm that I wanted to use, but did enough research to say no. The mechanical aperture pin on the lens may have prevented you from mounting it, which may be good because the pin may have also prevented you from removing it. They work fine on a Spotmatic, but the problem is that the pin is outside the threads. I don't have the lens anymore so it's a little hard to remember, look at it and the mount on the camera and you'll be able to figure it out. I think if you remove the pin it would work. I wasn't willing to do that with the one I had as it was too valuable to mod (I sold it for a nice profit). Do a little research and you'll find a little more info than I remember. They sure are nice looking lenses! Good luck with it.

Ira · 09-25-2010, 02:28 PM

Originally posted by ramseybuckeye

Ira, I'm no expert, but I had an SX 21mm that I wanted to use, but did enough research to say no. The mechanical aperture pin on the lens may have prevented you from mounting it, which may be good because the pin may have also prevented you from removing it. They work fine on a Spotmatic, but the problem is that the pin is outside the threads. I don't have the lens anymore so it's a little hard to remember, look at it and the mount on the camera and you'll be able to figure it out. I think if you remove the pin it would work. I wasn't willing to do that with the one I had as it was too valuable to mod (I sold it for a nice profit). Do a little research and you'll find a little more info than I remember. They sure are nice looking lenses! Good luck with it.

My problem was it wouldn't screw onto the adapter. It wouldn't catch.

I ripped out that pin, but didn't try it again. And it's been sitting on my window sill for a month.

Weird lens:

It screws apart into two pieces, and has a retractable lens hood. Also, the lens specs on it look like they're written on a FILTER, on the outside of the barrel, and not within the lip for the filter ring.

georgweb · 09-25-2010, 03:13 PM

Thanks for coming back Miguel. As you said the 2.8/60 seems to be a true macro lens and the color separation seems to give it a special look. I am no true macro guy so I will skip this lens, which is easy given the price hikes I am seeing with it.

Ira, I am not sure about the catching part, sounds like a threadstart-problem on either the adapter or the lens ? You are right about the grinding of the outer aperture ring, otherwise the SX-lenses won't mount properly on a Pentax DSLR.

That's what you get when you loosen the 3 back screws through the holes at about f/8. Watch out for the aperture ball !

Ground down and pin ripped out and aperture pin locked

Exposure+inf. correction: 0.25 mm ring of masking foil

Here's a link for a complete disass.: Sekor 2,8 / 135, disassembly and cleaning of the aperture

Good luck with the conversion !
Georg

Ira · 09-25-2010, 05:04 PM

Originally posted by georgweb

Ira, I am not sure about the catching part, sounds like a threadstart-problem on either the adapter or the lens ? You are right about the grinding of the outer aperture ring, otherwise the SX-lenses won't mount properly on a Pentax DSLR.

What I meant by catching is that the lens mount doesn't protrude enough into the M42 adapter to catch, because of the protruding rim around the perimeter of the lens .

knyghtfall · 09-25-2010, 08:03 PM

Originally posted by georgweb

Avoid the specular highlights :-) Seriously, I would either try to frame the background and blur it in pp (which of course does look overdone many times), or try to shoot full open as much as possible. All that is more academic than practical, I know.

I do shoot wide open quite often - in fact, stopping down is a relatively new thing I picked up recently when I started trying out macro

But I do appreciate the increase in IQ from stopping down. Am trying for a 16 bladed aperture lens, to see how it performs. Will keep your advice in mind, thanks for the pointer!

Originally posted by georgweb

Miguel & Nyghtfall, how would you judge your 2.8/60 performance in the mid-to-infinity department ? Reason for it, I am suspecting this lens to be a copy or a close friend of its Zeiss brethren, which is said to have eye-bleeding near performance (like your lenses obviously) but not so great inf. performance.

My experience with this lens would differ from miguel's. Not sure how you would define mid to long distance, but here are some pictures below I took with the mamiya 60mm

about 1.5m away:

about 4 - 5m away

this one should be at infinity focus. I PP'ed the colours to wash them out, nothing to do with the lens.

I find the lens still very sharp wide open at mid - long distances, and in fact there's little need for me to stop down, since I don't need to increase the DOF which is paper thin at close focusing distances.

knyghtfall · 09-28-2010, 05:41 PM

sharing one pic from the 60mm macro today:

knyghtfall · 10-02-2010, 08:46 PM

I replaced the voigtlander 58mm with this lens as a walkabout lens, because I wanted the added flexibility of close focus/macro which increases the range of possibilities. I walk for a walk in the park with it yesterday to try it out in this role, and here are some pictures I got:

first stop was among the flower bushes:

Moving along to the historical part of the park..
(most pictures at infinity focus)

knyghtfall · 10-02-2010, 08:55 PM

Moving along to the greener areas of the park:

Couldn't resist snapping at 2 eagles in the sky, even though 60mm is way too short for birding

Finally, sitting down at a park bench, and looking up:

some little critters were with me at my spot.

In summary, the mamiya 60mm is what I am looking for in a walkaround - great IQ, versatile, and has the capability to morph into a fully capable macro if you need one. DOF is thin enough to be a portrait lens especially closer up. Colours are a bit colour ( I suspect its b'cos of the colour space settings my my K20D, not really because of the lens). This len's a keeper.

Lacyt · 12-02-2010, 06:43 AM

A bit late to this discussion, but hey...

I just bought an "Auto Sears" 55mm f1.8 - F16 in M42 screw mount "Lens made in Japan". Reading through this thread, it doesn't seem to fit the descriptions of either Mamiya made or Ricoh made Sears lenses.

I wouldn't call it a "gem", per se, but it is nonetheless a very nice lens. Excellent bokeh, all metal construction, not sure about the coating but it resembles that of the Super Taks though it's not yellowed that I can tell, ridged/knurled focusing ring that's every bit as smooth as the Taks, has the Auto/Manual switch, and 52mm filter thread.

Any thoughts on the manufacturer of this lens?

Thanks in advance!

stevebrot · 12-02-2010, 11:00 PM

Originally posted by Lacyt

A bit late to this discussion, but hey...

I just bought an "Auto Sears" 55mm f1.8 - F16 in M42 screw mount "Lens made in Japan". Reading through this thread, it doesn't seem to fit the descriptions of either Mamiya made or Ricoh made Sears lenses.

I wouldn't call it a "gem", per se, but it is nonetheless a very nice lens. Excellent bokeh, all metal construction, not sure about the coating but it resembles that of the Super Taks though it's not yellowed that I can tell, ridged/knurled focusing ring that's every bit as smooth as the Taks, has the Auto/Manual switch, and 52mm filter thread.

Any thoughts on the manufacturer of this lens?

Thanks in advance!

Now that is interesting. Any idea what model Sears camera it was originally attached to?

Steve

georgweb · 02-02-2011, 01:37 PM

Bump, the above-mentioned lens does look very similar to Sears 55mm 1:1.8 m42 Lens Reviews - Pentax Third-Party Lens Review Database .

SX135/2.8 @f4(?) on K100D

SX2.8/28 @f/8(?) + cheapo circ-pol on K100D no pp

stover98074 · 02-02-2011, 08:14 PM

I have three Mamiya lenses.

1. 135 2.8 M42 Chrome Nose - I think I am the second user of this old lens and it has been stored for a long time.

2. Mamiya 645 80 2.8N ($50 at Keh) - here is a write up - a wonderful lens.

Mamiya 645 80mm f/2.8 Lens Review

3. Mamiya 645 150 3.5 N ($80 or so at Keh) - the photo below is a landscape with the 150 taken a week ago.

Ira · 02-03-2011, 04:34 AM

Think I'll try to get my 135 working this weekend.

Don't have a dremel, but I'll get a friend to do it.

georgweb · 02-03-2011, 12:48 PM

Originally posted by Ira

Think I'll try to get my 135 working this weekend.
Don't have a dremel, but I'll get a friend to do it.

Good luck ! You don't need a dremel, a file and some patience does the trick. Watch out for the aperture ball when pulling off the back.

Originally posted by stover98074

I have three Mamiya lenses.
...

Envy ! Can you recommend a good value Mamiya645 to PK (or M42) adapter ?

Nomad · 02-03-2011, 05:14 PM

Originally posted by Nomad

Hey all,
I picked up a 400mm 6.3 that is full manual ancd has no offending pin to get stuck. I have it mounted with an m42 to k adapter but did have to place a .012" shim between the lens and adapter to properly focus.

Funny that this thread popped up as I just listed this 400MM Mamiya lens in Ebay.

I picked up a Bigma

so the manual focus is going as I have issues with manual focus sometimes with my k10
Mamiya 400mm f6.3 Lens - Pentax mount - eBay (item 190497669940 end time Feb-04-11 18:23:16 PST)

09-25-2010, 08:03 PM	#50
knyghtfall Veteran Member Join Date: Jun 2007 Location: Singapore Photos: Gallery Posts: 348	Originally posted by georgweb Avoid the specular highlights :-) Seriously, I would either try to frame the background and blur it in pp (which of course does look overdone many times), or try to shoot full open as much as possible. All that is more academic than practical, I know. I do shoot wide open quite often - in fact, stopping down is a relatively new thing I picked up recently when I started trying out macro But I do appreciate the increase in IQ from stopping down. Am trying for a 16 bladed aperture lens, to see how it performs. Will keep your advice in mind, thanks for the pointer! Originally posted by georgweb Miguel & Nyghtfall, how would you judge your 2.8/60 performance in the mid-to-infinity department ? Reason for it, I am suspecting this lens to be a copy or a close friend of its Zeiss brethren, which is said to have eye-bleeding near performance (like your lenses obviously) but not so great inf. performance. My experience with this lens would differ from miguel's. Not sure how you would define mid to long distance, but here are some pictures below I took with the mamiya 60mm about 1.5m away: about 4 - 5m away this one should be at infinity focus. I PP'ed the colours to wash them out, nothing to do with the lens. I find the lens still very sharp wide open at mid - long distances, and in fact there's little need for me to stop down, since I don't need to increase the DOF which is paper thin at close focusing distances. Last edited by knyghtfall; 09-26-2010 at 01:56 AM.

10-02-2010, 08:46 PM	#52
knyghtfall Veteran Member Join Date: Jun 2007 Location: Singapore Photos: Gallery Posts: 348	the mamiya sekor 60mm Macro as a walk about lens I replaced the voigtlander 58mm with this lens as a walkabout lens, because I wanted the added flexibility of close focus/macro which increases the range of possibilities. I walk for a walk in the park with it yesterday to try it out in this role, and here are some pictures I got: first stop was among the flower bushes: Moving along to the historical part of the park.. (most pictures at infinity focus)

12-02-2010, 06:43 AM	#54
Lacyt New Member Join Date: Apr 2009 Location: Texas Posts: 16	Sears 55mm A bit late to this discussion, but hey... I just bought an "Auto Sears" 55mm f1.8 - F16 in M42 screw mount "Lens made in Japan". Reading through this thread, it doesn't seem to fit the descriptions of either Mamiya made or Ricoh made Sears lenses. I wouldn't call it a "gem", per se, but it is nonetheless a very nice lens. Excellent bokeh, all metal construction, not sure about the coating but it resembles that of the Super Taks though it's not yellowed that I can tell, ridged/knurled focusing ring that's every bit as smooth as the Taks, has the Auto/Manual switch, and 52mm filter thread. Any thoughts on the manufacturer of this lens? Thanks in advance! Attached Images

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09-25-2010, 12:03 PM	#46
ramseybuckeye Site Supporter Join Date: Apr 2009 Location: Hampstead, NC Photos: Gallery Posts: 17,294	Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here. Originally posted by Ira I just bought this lens, but it won't mount. Seems I have to grind down the perimeter near the mount. Did you do this too? Ira, I'm no expert, but I had an SX 21mm that I wanted to use, but did enough research to say no. The mechanical aperture pin on the lens may have prevented you from mounting it, which may be good because the pin may have also prevented you from removing it. They work fine on a Spotmatic, but the problem is that the pin is outside the threads. I don't have the lens anymore so it's a little hard to remember, look at it and the mount on the camera and you'll be able to figure it out. I think if you remove the pin it would work. I wasn't willing to do that with the one I had as it was too valuable to mod (I sold it for a nice profit). Do a little research and you'll find a little more info than I remember. They sure are nice looking lenses! Good luck with it.

09-25-2010, 02:28 PM	#47
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	Originally posted by ramseybuckeye Ira, I'm no expert, but I had an SX 21mm that I wanted to use, but did enough research to say no. The mechanical aperture pin on the lens may have prevented you from mounting it, which may be good because the pin may have also prevented you from removing it. They work fine on a Spotmatic, but the problem is that the pin is outside the threads. I don't have the lens anymore so it's a little hard to remember, look at it and the mount on the camera and you'll be able to figure it out. I think if you remove the pin it would work. I wasn't willing to do that with the one I had as it was too valuable to mod (I sold it for a nice profit). Do a little research and you'll find a little more info than I remember. They sure are nice looking lenses! Good luck with it. My problem was it wouldn't screw onto the adapter. It wouldn't catch. I ripped out that pin, but didn't try it again. And it's been sitting on my window sill for a month. Weird lens: It screws apart into two pieces, and has a retractable lens hood. Also, the lens specs on it look like they're written on a FILTER, on the outside of the barrel, and not within the lip for the filter ring.

09-25-2010, 03:13 PM	#48
georgweb Veteran Member Join Date: Apr 2008 Location: Berlin, Germany Photos: Gallery Posts: 1,386	Thanks for coming back Miguel. As you said the 2.8/60 seems to be a true macro lens and the color separation seems to give it a special look. I am no true macro guy so I will skip this lens, which is easy given the price hikes I am seeing with it. Ira, I am not sure about the catching part, sounds like a threadstart-problem on either the adapter or the lens ? You are right about the grinding of the outer aperture ring, otherwise the SX-lenses won't mount properly on a Pentax DSLR. That's what you get when you loosen the 3 back screws through the holes at about f/8. Watch out for the aperture ball ! Ground down and pin ripped out and aperture pin locked Exposure+inf. correction: 0.25 mm ring of masking foil Here's a link for a complete disass.: Sekor 2,8 / 135, disassembly and cleaning of the aperture Good luck with the conversion ! Georg

09-25-2010, 05:04 PM	#49
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	Originally posted by georgweb Ira, I am not sure about the catching part, sounds like a threadstart-problem on either the adapter or the lens ? You are right about the grinding of the outer aperture ring, otherwise the SX-lenses won't mount properly on a Pentax DSLR. What I meant by catching is that the lens mount doesn't protrude enough into the M42 adapter to catch, because of the protruding rim around the perimeter of the lens .

09-28-2010, 05:41 PM	#51
knyghtfall Veteran Member Join Date: Jun 2007 Location: Singapore Photos: Gallery Posts: 348	sharing one pic from the 60mm macro today:

10-02-2010, 08:55 PM	#53
knyghtfall Veteran Member Join Date: Jun 2007 Location: Singapore Photos: Gallery Posts: 348	Moving along to the greener areas of the park: Couldn't resist snapping at 2 eagles in the sky, even though 60mm is way too short for birding Finally, sitting down at a park bench, and looking up: some little critters were with me at my spot. In summary, the mamiya 60mm is what I am looking for in a walkaround - great IQ, versatile, and has the capability to morph into a fully capable macro if you need one. DOF is thin enough to be a portrait lens especially closer up. Colours are a bit colour ( I suspect its b'cos of the colour space settings my my K20D, not really because of the lens). This len's a keeper.

12-02-2010, 11:00 PM	#55
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Lacyt A bit late to this discussion, but hey... I just bought an "Auto Sears" 55mm f1.8 - F16 in M42 screw mount "Lens made in Japan". Reading through this thread, it doesn't seem to fit the descriptions of either Mamiya made or Ricoh made Sears lenses. I wouldn't call it a "gem", per se, but it is nonetheless a very nice lens. Excellent bokeh, all metal construction, not sure about the coating but it resembles that of the Super Taks though it's not yellowed that I can tell, ridged/knurled focusing ring that's every bit as smooth as the Taks, has the Auto/Manual switch, and 52mm filter thread. Any thoughts on the manufacturer of this lens? Thanks in advance! Now that is interesting. Any idea what model Sears camera it was originally attached to? Steve

02-02-2011, 01:37 PM	#56
georgweb Veteran Member Join Date: Apr 2008 Location: Berlin, Germany Photos: Gallery Posts: 1,386	Bump, the above-mentioned lens does look very similar to Sears 55mm 1:1.8 m42 Lens Reviews - Pentax Third-Party Lens Review Database . SX135/2.8 @f4(?) on K100D SX2.8/28 @f/8(?) + cheapo circ-pol on K100D no pp

02-02-2011, 08:14 PM	#57
stover98074 Senior Member Join Date: Apr 2010 Location: Seattle Photos: Gallery Posts: 153	I have three Mamiya lenses. 1. 135 2.8 M42 Chrome Nose - I think I am the second user of this old lens and it has been stored for a long time. 2. Mamiya 645 80 2.8N ($50 at Keh) - here is a write up - a wonderful lens. Mamiya 645 80mm f/2.8 Lens Review 3. Mamiya 645 150 3.5 N ($80 or so at Keh) - the photo below is a landscape with the 150 taken a week ago.

02-03-2011, 04:34 AM	#58
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	Think I'll try to get my 135 working this weekend. Don't have a dremel, but I'll get a friend to do it.

02-03-2011, 12:48 PM	#59
georgweb Veteran Member Join Date: Apr 2008 Location: Berlin, Germany Photos: Gallery Posts: 1,386	Originally posted by Ira Think I'll try to get my 135 working this weekend. Don't have a dremel, but I'll get a friend to do it. Good luck ! You don't need a dremel, a file and some patience does the trick. Watch out for the aperture ball when pulling off the back. Originally posted by stover98074 I have three Mamiya lenses. ... Envy ! Can you recommend a good value Mamiya645 to PK (or M42) adapter ?

02-03-2011, 05:14 PM	#60
Nomad Veteran Member Join Date: Dec 2009 Location: Maine Photos: Gallery \| Albums Posts: 408	Originally posted by Nomad Hey all, I picked up a 400mm 6.3 that is full manual ancd has no offending pin to get stuck. I have it mounted with an m42 to k adapter but did have to place a .012" shim between the lens and adapter to properly focus. Funny that this thread popped up as I just listed this 400MM Mamiya lens in Ebay. I picked up a Bigma so the manual focus is going as I have issues with manual focus sometimes with my k10 Mamiya 400mm f6.3 Lens - Pentax mount - eBay (item 190497669940 end time Feb-04-11 18:23:16 PST)