Mamiya 105 D TLR Lens

[Grim Tuesday]

I am trying to figure out what is going on with this lens. I often have trouble remembering which lens I was shooting with especially when focal lengths are close, so I shot an entire roll with my Mamiya 105 D, and then an entire roll with my 80mm right after. I developed them, and the results were clear: my beat up chrome 80 was much, much sharper. And more contrast, and higher resolution. Don't get me wrong, my lens isn't put together backwards or tilted or misalgned (I think). I tested alignment with a loupe and ground glass on the film plane and it looked good. But compared to the 80, which is razor sharp, the 105 just isn't. My copy doesn't really catch up until f16. Is this sample variation or a purpose-made portrait lens by Mamiya with a little bit of undocumented softness? Does anyone else have experience with this lens that can comment on it? I'm trying to decide if I should try to get a new one or leave the focal length out of my camera bag.

 

[MattKing]

Condition or sample variation.
Is it a 105mm D or 105mm DS - the DS being the version with depth of field preview?

 

[Grim Tuesday]

It is the "D" without the DoF preview, though I've always heard that D and DS are optically the same. Maybe they use the same 5 elements but aren't spaced exactly the same, I've always wondered why Mamiya made two versions of the same focal length at the same time. I know the D/DS is a 5 element design compared to the chrome shutter ones which are 4 elements.

 

[MattKing]

The black 105 mm f/3.5 non D version which (I believe) preceded the D version is the same optical design as the old chrome version.
I expect that they weren't all being produced at the same time.
In addition to offering depth of field preview, the DS lens offered a self-timer function.
I believe that within the black 105mm lenses, the D replaced the non-D, and the DS replaced the D.
If I am incorrect, hopefully Graham Patterson will chime in.
Is there any chance your problem is with focusing and not overall resolution and contrast?

 

[grat]

At least one of my Mamiya TL lenses has a small shim ring between the lens body and the housing, suggesting that some variance existed. The other question would be if the taking lens elements are snugly screwed together.

You said you checked the film plane with a piece of ground glass-- did you check the viewfinder at the same time (I assume yes, but it's worth asking) to make sure they were equally sharp?

 

[flavio81]

I am trying to figure out what is going on with this lens. I often have trouble remembering which lens I was shooting with especially when focal lengths are close, so I shot an entire roll with my Mamiya 105 D, and then an entire roll with my 80mm right after. I developed them, and the results were clear: my beat up chrome 80 was much, much sharper. And more contrast, and higher resolution. Don't get me wrong, my lens isn't put together backwards or tilted or misalgned (I think). I tested alignment with a loupe and ground glass on the film plane and it looked good. But compared to the 80, which is razor sharp, the 105 just isn't. My copy doesn't really catch up until f16. Is this sample variation or a purpose-made portrait lens by Mamiya with a little bit of undocumented softness? Does anyone else have experience with this lens that can comment on it? I'm trying to decide if I should try to get a new one or leave the focal length out of my camera bag.

Some alignment must be wrong. f16 until sharp is too much.

 

[Grim Tuesday]

Yeah, I was looking at both finder and ground glass, so I don't think there is an alignment problem. And Flavio, I should have been more clear, what I meant was it doesn't catch up to the 80mm until f16. It is "sharp" at f5.6. Just not razor sharp especially when viewed side by side with the 80mm

 

[hashtagquack]

I have a 105 DS and haven't found it to be lacking in the sharpness department although I don't have the 80mm to compare to. Compared to other 6x6 80mm lenses however it is comparable.
It could be issue with that specific example, eg it is possible for people to swap the taking and viewing lens so someone may have done this in the past.... If you're not sure if it is the newer 5 element version you can check infinity on the focus scale. The 5 element DS required a separate scale from the older 105 due to a different back focus distance and its identified on the scale with DS.

 

[Grim Tuesday]

I have a 105 DS and haven't found it to be lacking in the sharpness department although I don't have the 80mm to compare to. Compared to other 6x6 80mm lenses however it is comparable.
It could be issue with that specific example, eg it is possible for people to swap the taking and viewing lens so someone may have done this in the past.... If you're not sure if it is the newer 5 element version you can check infinity on the focus scale. The 5 element DS required a separate scale from the older 105 due to a different back focus distance and its identified on the scale with DS.

That's an interesting angle about someone swapping front groups. Does anyone know if there's a general rule to Mamiya TLR lenses for the lens serial numbers, like does the higher one always go for the viewing lens? Or is it just complete lens anarchy.

 

[Mamiya_Repair]

Just to clarify the various versions of the Mamiya 105mm TLR lenses as there were six different styles with three different optical formulas:

1.)Chrome, four element
2.)Black early version with sync terminal at right angle to the body, four element
3.)Black later version with sync terminal parallel to the lenses, slightly different top and bottom filter rings, four element
4.)Black early D version with four element lens (similar to the five element but front element is a singlet), you can identify this lens by measuring the distance from the front of the filter ring to the back of the lens mount and it would be 34.95mm, the later D lens measures 36.25mm.
5.)Black later version D with five element lens
6.)Black DS version with five element lens.

There are indeed shims between the taking and viewing lenses. Four different sizes to adjust the lenses so that they tracked focus properly. This is the first thing that I do when a Mamiya TLR lens comes into the shop- check that both lenses are focusing infinity at the same place.

As for swapping taking and viewing lenses, they are both the same on the 105mm and when these were available through Mamiya, we ordered one set (front and back) for either taking or viewing. With just a few exceptions, this is how most Mamiya TLR lenses are set up.

 

[Bormental]

Yeah, I was looking at both finder and ground glass, so I don't think there is an alignment problem. And Flavio, I should have been more clear, what I meant was it doesn't catch up to the 80mm until f16. It is "sharp" at f5.6. Just not razor sharp especially when viewed side by side with the 80mm

FWIW, I am new to the C-system, and I observed something similar. The first C330 body I bought came with a 105mm DS. The photos came out great, but while pixel-peeping I noticed overall "softer" character compared to Fujinon on my GF670. Perhaps not so much in the sharpness area, but maybe a bit less contrast? Unfortunately, that lens had a shutter issue and the seller replaced it with a (newer looking) 80mm f/2.8. Same film, same developer, and I am seeing the same "punch" as I do with the Fujinon. Again, we're talking about just two rolls shot with two ancient lenses, but hey it's a data point.

 

[flavio81]

Yeah, I was looking at both finder and ground glass, so I don't think there is an alignment problem. And Flavio, I should have been more clear, what I meant was it doesn't catch up to the 80mm until f16. It is "sharp" at f5.6. Just not razor sharp especially when viewed side by side with the 80mm

Oh...

Then I'm afraid this is how it was intended to be. For a 105/3.5 lens a Tessar would give razor sharpness at f8-11 with plenty of punchy contrast. The Heliar formula was later chosen by Mamiya for giving a smoother out of focus rendering; not for increased sharpness or contrast.

 

[MattKing]

It certainly wouldn't surprise me to find the 105mm emphasizing resolution and tonal transition, while the 80mm puts more emphasis on contrast, including in particular acutance (edge contrast). Acutance is, of course, the component that has the largest affect on our subjective perception of sharpness.

 

[Mackinaw]

I used for years on my Mamiya C220. A 105 DS lens. A Heliar optical design if I'm right. I was always happy with my pics from that lens. BTW, the "S" in DS stands for "self-timer." A DS lens has a depth of field ring and a self-timer.

Jim B.

 

[lenshood]

Apologies if it’s inappropriate to tack this on, but the timing of this post is uncanny: I have a black 55mm lens for my C3, and I noticed today that it’s pretty soft at open apertures (i.e., 5.6 and wider). Anyone else notice this?

 

[Grim Tuesday]

Not a real data point from me about the 55, but I've never heard of it being the best lens in the system. It's the only one I have never had in my hands myself. The reason being, I think most people seem to think it is the worst lens in the system, and it's expensive. The lens designs for the TLR series was constrained by the need to make the front element relatively small so two of them could be fit in the inter-lens distance. This made wide-angle design particularly difficult. Take a look at the size of the big honking front element on the Pentax 6x7 55 f3.5, it's like 100mm compared to the dainty Mamiya. I think this was partly counterbalanced by not needing to design around the mirror flopping up as you would in a SLR. But there is still a mirror there for the viewing lens, so still a constraint compared to a rangefinder or view camera. Anyways, I've never heard as much praise for the 55 as I have for the other lenses, so it doesn't seem out of the question that it would be softish up until f8-f11.

 

[mrosenlof]

I have both the 55mm and a 105DS. I consider them both to be good sharp lenses. FWIW

 

[Neil Grant]

...the 55mm is the optically the most complex in the C-series line up of lenses - maybe it's just the most difficult to get 'right' at manufacture. I have all the lenses except the 250mm and they are all really good performers - even the 55mm. The only thing you need to careful of is flare. Pointing into the light, the lens easily produces sharply defined pentagons from it's five bladed diaphragm.

 

[flavio81]

Apologies if it’s inappropriate to tack this on, but the timing of this post is uncanny: I have a black 55mm lens for my C3, and I noticed today that it’s pretty soft at open apertures (i.e., 5.6 and wider). Anyone else notice this?

There is a lot of sample variation with the 55mm.

The copy i had, was sharp at 5.6.

 

[lenshood]

There is a lot of sample variation with the 55mm.

The copy i had, was sharp at 5.6.

Well, considering how much was off with this camera when I bought it, I guess I shouldn’t be surprised I got a bad sample. Not that I mean to complain! I love this camera. And I almost always stop down to 11 or 16, so it won’t derail me too much.

 

[lenshood]

...the 55mm is the optically the most complex in the C-series line up of lenses - maybe it's just the most difficult to get 'right' at manufacture. I have all the lenses except the 250mm and they are all really good performers - even the 55mm. The only thing you need to careful of is flare. Pointing into the light, the lens easily produces sharply defined pentagons from it's five bladed diaphragm.

Yes, I’ve had my share of flare issues. A bit annoying, if occasionally accidentally beautiful. Thanks for the reply.

 

[lenshood]

Not a real data point from me about the 55, but I've never heard of it being the best lens in the system. It's the only one I have never had in my hands myself. The reason being, I think most people seem to think it is the worst lens in the system, and it's expensive. The lens designs for the TLR series was constrained by the need to make the front element relatively small so two of them could be fit in the inter-lens distance. This made wide-angle design particularly difficult. Take a look at the size of the big honking front element on the Pentax 6x7 55 f3.5, it's like 100mm compared to the dainty Mamiya. I think this was partly counterbalanced by not needing to design around the mirror flopping up as you would in a SLR. But there is still a mirror there for the viewing lens, so still a constraint compared to a rangefinder or view camera. Anyways, I've never heard as much praise for the 55 as I have for the other lenses, so it doesn't seem out of the question that it would be softish up until f8-f11.

Thanks for the detail - makes sense.

 

[flavio81]

Well, considering how much was off with this camera when I bought it, I guess I shouldn’t be surprised I got a bad sample. Not that I mean to complain! I love this camera. And I almost always stop down to 11 or 16, so it won’t derail me too much.

So, the big white elephant in the room is...

Have you repaired the foam that presses the ground glass against its proper seat in the camera?

If not, all lenses will have sharpness problems.

 

[Grim Tuesday]

So, the big white elephant in the room is...

Have you repaired the foam that presses the ground glass against its proper seat in the camera?

If not, all lenses will have sharpness problems.

I have a question about that. On my camera, a C330 (non F or S) the foam is between the ground glass/plastic/fresnel piece and the clear glass top that protects it. The ground glass itself rests on three studs rising above the mirror, and that position doesn't seem to change based on the foam. I've seen on other forums, people talk about how the foam can affect focus position but I don't understand how it does. I almost wonder if it's an urban myth. The case I could see it affecting focus is if the foam is dry and gluey, and the screen is glued to the top of the frame instead of being pushed down to the studs. But other than this rare case, is there any other way it can happen?

 

[flavio81]

I have a question about that. On my camera, a C330 (non F or S) the foam is between the ground glass/plastic/fresnel piece and the clear glass top that protects it. The ground glass itself rests on three studs rising above the mirror, and that position doesn't seem to change based on the foam. I've seen on other forums, people talk about how the foam can affect focus position but I don't understand how it does. I almost wonder if it's an urban myth. The case I could see it affecting focus is if the foam is dry and gluey, and the screen is glued to the top of the frame instead of being pushed down to the studs. But other than this rare case, is there any other way it can happen?

This is not an urban myth, it's an objective fact that can easily be inferred by taking a look at the assembly.

The foam should be in a position that presses the frosted groundglass (actually an acrylic piece) against the four studs that are in the camera body.

Almost ALL C330 cameras i've seen have this foam rotten. I replaced it in my screens, this is something you can do with a little patience. This isn't a "rare" case, it's the most common case!