Sekor Z 110 2,8 - difference between non-W and W

[Tor-Einar Jarnbjo]

It seems quite difficult to find detailed information about the different versions of the Sekor Z lenses online. If I understand it correctly, the original lenses had no extra designation, then later, all (or at least most) models came in a W-version with half-stop aperture settings and for some of the models, there are even newer versions with different names, e.g the 50mm USD, the 65mm L-A or the APO tele lenses.

All the 'post W' versions seem to come with an improved optical system as well, but is there any difference in the optics between the original non-W and the later W versions?

I am particularly interested in the differences between the original 110mm f2.8 non-W and the later W version. I am considering buying such a lens and even if the price difference is not that high, it seems easier to find the non-W version. If the only difference is the half-stop aperture ring, I can very well live with the older version, but if there are any optical improvements in the W version, I might just as well wait a bit for a chance to get such a specimen.

 

[TheFlyingCamera]

I'll look and see at home which one I have, but I seriously doubt you'll have any issues with performance of even the non-W version.

 

[TheFlyingCamera]

Ok- I finally checked my lens - it's a plain-Jane 110 non-W, with just the whole stops clicked. If the half-stops having click-stops to them is important, get the lens that does it. If not, I doubt you'll ever have any complaints optically about it. That, or any other Mamiya lens for that matter.

 

[Stephen Prunier]

I have the current version of the 110 2.8 Z W.
It has markings for 1/2 stops, but it doesn't actually click in place. It only does that for the whole stops.
Hope this is helpful for you.

 

[Tor-Einar Jarnbjo]

Ok- I finally checked my lens - it's a plain-Jane 110 non-W, with just the whole stops clicked. If the half-stops having click-stops to them is important, get the lens that does it. If not, I doubt you'll ever have any complaints optically about it.

Sorry, but this does not answer my question if there are any optical differences between the two versions of the lens.

That, or any other Mamiya lens for that matter.

That might be, but most of what I have read about the Mamiya Z lenses contradict your statement. At least the older versions do not exactly have the sharpest reputation, pun intended. The quality differences also seem to be reflected by the market prices. A 90mm non-W lens can be had for around US$ 40, while 110mm W lenses usually go for at least US$ 300. I would be surprised if there is no reason for such a significant price difference.

 

[TheFlyingCamera]

Sorry, but this does not answer my question if there are any optical differences between the two versions of the lens.



That might be, but most of what I have read about the Mamiya Z lenses contradict your statement. At least the older versions do not exactly have the sharpest reputation, pun intended. The quality differences also seem to be reflected by the market prices. A 90mm non-W lens can be had for around US$ 40, while 110mm W lenses usually go for at least US$ 300. I would be surprised if there is no reason for such a significant price difference.

Well, the 90mm and the 110mm are two different lenses. That's a big difference in the price right there. The 110 regardless of version is a much more sought-after lens.

You're right, I don't have any scientific data to back up my claim. I only have personal experience to say that I am very happy with my 110mm non-W. As I am with all of my RZ glass. I don't have the FLE versions of the 65 or the 50, but they scan and print just fine.

 

[halfaman]

110 mm optical desing is the same in W and non-W versions, the difference between both of them is just the half stops marks.

By the way, the only difference between 65 mm L-A a non L-A is the floating element to improve corners shaprness in close focusing. Besides that the optical desing is the same.

50 mm ULD has floating element but this time it has also completely different optical design compared to standard 50 mm and a suberb lens.

 

[Tor-Einar Jarnbjo]

Well, the 90mm and the 110mm are two different lenses. That's a big difference in the price right there. The 110 regardless of version is a much more sought-after lens.

And my assumption, from what I have read, is that the reason why the 110mm lens is much more sought-after is simply that it is much better than the 90mm lens. It may very well be, that all Mamiya RZ lenses are good (for any arbitrary subjective definition of 'good'), but both rumors and prices seem to clearly indicate that some lenses are less good and some lenses are more good.

You're right, I don't have any scientific data to back up my claim. I only have personal experience to say that I am very happy with my 110mm non-W. As I am with all of my RZ glass. I don't have the FLE versions of the 65 or the 50, but they scan and print just fine.

And my personal experience is that I am also happy with my 135 equipment with its sharp lenses, light weight. I can also both scan and print 135 negatives 'just fine'. When I bother to carry around and use my MF equipment and spend the extra bang for the more expensive film material, it is because I seek for the additional quality reserves I expect to find in the exposures. Even if I don't need it right away, I at least anticipate the need for a sharper or larger print or a higher resolution scan. Since my current MF equipment is getting annoyingly unreliable, I am considering switching completely to a new system and the RZ67 seems to be a reasonable candidate, though big and bulky. Getting below-par lenses (and from what I have read, there are several Sekor Z lenses which fall into that category) is therefore pretty pointless. Shooting with a soft lens on MF may very well not give much more sharpness and details in the exposure than shooting on 135 film with a good lens.

 

[Tor-Einar Jarnbjo]

110 mm optical desing is the same in W and non-W versions, the difference between both of them is just the half stops marks.

By the way, the only difference between 65 mm L-A a non L-A is the floating element to improve corners shaprness in close focusing. Besides that the optical desing is the same.

50 mm ULD has floating element but this time it has also completely different optical design compared to standard 50 mm and a suberb lens.

Thanks a lot! Finally simply an answer to my question

 

[EdSawyer]

All the 110s are the same optically. None of the RZ lenses are bad. I have about 17 of them currently and have had more in the past. Even the ones that get snubbed like the non-ULD 50 are superb, and the simple 180mm tessar is also excellent. Seriously, check the Chris Perez lens tests, these are world-class lenses by any measure really. THe RZ is a superb system, the most robust and full-featured of any medium format system I think. And the prices are ridiculously cheap compared to when new. That 110 was $1500+ back in the day, so getting one for $200-300 is a steal. Likewise for the rest of the system, pennies on the dollar these days.

 

[Tor-Einar Jarnbjo]

All the 110s are the same optically. None of the RZ lenses are bad. I have about 17 of them currently and have had more in the past. Even the ones that get snubbed like the non-ULD 50 are superb, and the simple 180mm tessar is also excellent. Seriously, check the Chris Perez lens tests, these are world-class lenses by any measure really. THe RZ is a superb system, the most robust and full-featured of any medium format system I think. And the prices are ridiculously cheap compared to when new. That 110 was $1500+ back in the day, so getting one for $200-300 is a steal. Likewise for the rest of the system, pennies on the dollar these days.

If you are refering to this lens test page, that is actually one of the reasons why I am not quite convinced about any alleged world-class quality of the Sekor Z lenses. I can't find any information on Chris Perez' pages at which MTF ratio he is testing, so it is difficult to compare his numbers with other lens tests. Assuming that he is measuring at MTF50 (which seem to be the usual contrast), the Sekor Z 180mm W-N lens with his value of 60 l/mm does for example not compare very well with my 135 film Nikon 85mm (similar equivalent focal length), which clocks in at about 95 l/mm. Much of the advantage of a larger 6x7 negative compared to a 135 negative would be lost due to the lower lens resolution.

Even if I compare apples with apples (instead of pears) and look at many of the other lenses on Chris Perez' page (e.g. the Zeiss lenses for Hasselblad, the newer Mamiya 7 or the Rolleiflex lenses), the Sekor Z lenses are honestly not coming out very well.

 

[MattKing]

One thing that Chris Perez's data indicates is that the Mamiya RZ lenses yield much more consistent resolution results over the range of apertures than the Hasselblad lenses do. They also tend to be more consistent across the field (centre, middle and corner) than the Hasselblad lenses.
In either case, all of the resolution numbers - Hasselblad or Mamiya - are excellent. And with the reduced need for enlargement (6 x 7 vs effectively 4.5 x 6 negatives) the Mamiya resolution numbers are effectively better than the Hasselblad ones.
If resolution numbers are your main criteria, the Mamiya 7 should be your choice.

 

[TheFlyingCamera]

If you are refering to this lens test page, that is actually one of the reasons why I am not quite convinced about any alleged world-class quality of the Sekor Z lenses. I can't find any information on Chris Perez' pages at which MTF ratio he is testing, so it is difficult to compare his numbers with other lens tests. Assuming that he is measuring at MTF50 (which seem to be the usual contrast), the Sekor Z 180mm W-N lens with his value of 60 l/mm does for example not compare very well with my 135 film Nikon 85mm (similar equivalent focal length), which clocks in at about 95 l/mm. Much of the advantage of a larger 6x7 negative compared to a 135 negative would be lost due to the lower lens resolution.

Even if I compare apples with apples (instead of pears) and look at many of the other lenses on Chris Perez' page (e.g. the Zeiss lenses for Hasselblad, the newer Mamiya 7 or the Rolleiflex lenses), the Sekor Z lenses are honestly not coming out very well.

I think you've got some bad math going - compare the size difference to the lp/mm - your 35mm negative at 95 lp/mm has 50% more resolution per square inch, but the 6x7 has roughly 4x the square inches. So in the end you're still getting double the total line-pairs. 35mm lenses HAVE to have higher resolution to even begin to keep up because they just don't have the same total information density as larger formats. If you think the decline in resolution going to 6x7 from 90-60 lp/mm is bad, try looking at what an 8x10 lens will give you - 30-40 lp/mm. But you're dealing with 53x the square inches.

 

[Tor-Einar Jarnbjo]

I think you've got some bad math going - compare the size difference to the lp/mm - your 35mm negative at 95 lp/mm has 50% more resolution per square inch, but the 6x7 has roughly 4x the square inches. So in the end you're still getting double the total line-pairs. 35mm lenses HAVE to have higher resolution to even begin to keep up because they just don't have the same total information density as larger formats. If you think the decline in resolution going to 6x7 from 90-60 lp/mm is bad, try looking at what an 8x10 lens will give you - 30-40 lp/mm. But you're dealing with 53x the square inches.

If you compare resolution per area and not resolution per length, you have to square the difference. A lens with 95lp/mm will give you about 2.5 times - (95/60)² - the resolution per area as a lens with 60lp/mm.

If you compare (line pairs per image height) multiplied with (line pairs per image width), you will get the following numbers (Mlp² being million line pairs squared):

- 95lp/mm on a 135 negative: 7.8 Mlp²
- 60lp/mm on a 6x7 negative: 14 Mlp² (Sekor Z 180mm W-N from Perez' table)
- 85lp/mm on a 6x6 negative: 23 Mlp² (150mm f/4 Sonnar CT* for Hasselblad from Perez' table)
- 120lp/mm on a 6x7 negative: 56 Mlp² (Mamiya 7 80mm from Perez' table)
- 30lp/mm on a 8x10" negative: 46 Mlp²
- 40lp/mm on a 8x10" negative: 83 Mlp²

And even 95lp/mm is not really top-notch for a 135 lens, it was just a number I found on the fly for my cheapish Nikon 85mm AF-D lens. I actually found that number to be unrealisticly low and other tests I've found quote numbers around 150lp/mm, which sound much more realistic. 150lp/mm on a 135 negative would give 19 Mlp² and exceed the resolution you can obtain with 60lp/mm on a 6x7 negative.

 

[halfaman]

Stop the math, really. No one in this Universe had any complaint about sharpness in a Mamiya RZ or RB system. Some of the best lenses ever get in my hands, including digital, are Sekor Z.

 

[iakustov]

RZ system is superb.
If you don't get sharp images with RZ lenses, than most likely you are doing something wrong.

 

[Tor-Einar Jarnbjo]

Stop the math, really. No one in this Universe had any complaint about sharpness in a Mamiya RZ or RB system. Some of the best lenses ever get in my hands, including digital, are Sekor Z.

You might not have seen much of the universe. There are plenty of people writing on the net about the deficiencies of some of the Sekor Z lenses. Particularly the old 50mm version and the 180mm lens is often said to be soft and at least the lack of sharpness from the 180 lens is confirmed in objective numbers in the lens tests by Chris Perez. And this is not just about math. If the lens does not resolve more than 55-60 lp/mm, I would expect the lack of sharpness to be apparent in prints about 12x16" and larger.

Then there are some RZ67 users like you and iakustov, who seem to show an allergic reaction when someone just suggests that the RZ67 system is not superior. I suppose that you are either not using your equipment for purposes where the lack of quality become obvious (large prints or crops) or you are simply refusing to acknowledge shortages in the equipment you have paid a lot of money for.

 

[halfaman]

First of all... cool yourself!. It is better for good discussions

I know about complaints on the standard 50 mm being "soft", I had it and it is a nice lens. It pales in comparison to the magnificient ULD version but it is perfectlly usable stopping down a bit, even I recognize it is the weakest lens I tried of RZ system and 65 mm would be a better choice for someone looking just for sharpness.

But say the standard 180 mm W-N is soft.... nonsense. Again, the 210 mm APO is breathtaking (specially in color film) but it doesn't mean that the 180 mm is bad at all. It is so good that I keep it even I have the 210 mm APO and for certain circunstancies is my choice for portraits (handheld close focusing).

If you need more information, I can tell you that the 110 mm f/2.8 is absolutely wonderful. Somebody asked me for advice about top notch lenses of RZ system, my asnwer was that he already had one... The 110 mm! And what about this comment of Chris Perez... "Oh well, the Hasselblad still wins the day... but you certainly can't tell from looking at the final prints"

You may be also interested in that I own a Zenzanon-PS 40 mm. You can find a thread with somebody complaining about corner sharpness, I read it, and you can check the results of Chris Perez page. Let me tell you one thing... It is a gorgeous lens! A fantastic wide angle and my favourite of all Bronica SQ system. Just for the record I didn't like the Zenzanon-PS 50 mm at all, 65 mm is much better.

Conclusion: Real world is not in graphics and numbers... Photography is about taste.

 

[iakustov]

Then there are some RZ67 users like you and iakustov, who seem to show an allergic reaction when someone just suggests that the RZ67 system is not superior. I suppose that you are either not using your equipment for purposes where the lack of quality become obvious (large prints or crops) or you are simply refusing to acknowledge shortages in the equipment you have paid a lot of money for.

Ok, name the system which is superior then?
I enlarged onto 12''x16'' and larger from 6x7 negative taken with 180mm RZ lens (cheapest in the line!) and I can tell you those were super sharp.
With naked eyes, I doubt you will see a difference on 12''x16'' paper properly enlarged from a sharp 6x7 or 6x6 negative if taken with any modern lens be it Zeiss or from Mamiya.
And regarding the prices for RZ lens - those are super cheap in comparison to cost of the film and paper. If only you keep staring at MTF charts online and not exposing film thru these fantastic lenses.

 

[EdSawyer]

yeah, as mentioned, enough with the measurebating.

here's what I have for MF systems to compare with, so you can judge my judgement:
Mamiya 7 with all the lenses
RZ67 with at least 15-17 lenses
Fuji GSW690III and GW670III
Rolleiflex 3.5F planar
Bessa II color heliar
Kodak Tourist II with Anastar
and a ton of LF glass

That said, the Mamiya 7 is tops for outright sharpness. RZ67 is 2nd, and not by much if at all in some focal lengths. (particularly the apo teles and floating element 65) 3rd would be a tossup between the Fujis and the Rollei, then next the Anastar, very close also. The Color heliar is also very sharp, on par with the anastar. Honestly it's hard to go wrong with any of them. Even the humble $50 tourist with a tessar (ektar) and front-cell focusing is damn sharp when focused well and shot at f/8-11 or so.

-Ed

 

[Soeren]

There is nothing thatll ruin the joy of photography like specfetichism and measurebation