Hi

If you doubt my word, try a google of"Mamiya 7 users travelphoto.com,
under Ken Rockwerll.

DON

I can find no comparative lens test of the M7 43mm and the vintage Zeiss???
Once again, re read my post, I was not questioning the basis of the design... I simple
stated, they had drastic difference in optical performance..... get it?

b

>
> If you doubt my word, try a google of"Mamiya 7 users travelphoto.com,
> under Ken Rockwerll.
>
> DON
>
>

> I can find no comparative lens test of the M7 43mm and the vintage Zeiss???
> Once again, re read my post, I was not questioning the basis of the design... I simple
> stated, they had drastic difference in optical performance..... get it?

No, I don't get it, as I have not seen a performance test of the Mamiya
M7 43mm lens,but maybe you did not notice that the Biogon 38mm lens was
tested by C. Perez, though the year of the test was not listed, as is
his style. Therefore I have NO WAY of knowing whether it was a 'vintage'
1954 Biogon lens or a current model Biogon lens. Please inform us what
the, "drastic differences in optical performance " are. And how were,
these, "drastic differences", measured?

Incidentally, I own 3- 21mm Zeiss Biogon lenses, purchased in 1960's and
they are high resolution lenses. I used to shoot twin camera 35mm stereo
with them, in the 1960's-1970's.

DON

Here are results from Perez for Mamiya 7 80mm lens....

120 120 60 *f/4*
120 120 68 *f5.6
*120 107 68 *f/8*
107 107 76 *f/11


See if you can find any 1950's lenses that are in this league, specially at f4.... OK?

Bill

**


**


*

On 9/28/2011 5:08 PM, Don Lopp wrote:
>> I can find no comparative lens test of the M7 43mm and the vintage Zeiss???
>> Once again, re read my post, I was not questioning the basis of the design... I simple
>> stated, they had drastic difference in optical performance..... get it?
> No, I don't get it, as I have not seen a performance test of the Mamiya
> M7 43mm lens,but maybe you did not notice that the Biogon 38mm lens was
> tested by C. Perez, though the year of the test was not listed, as is
> his style. Therefore I have NO WAY of knowing whether it was a 'vintage'
> 1954 Biogon lens or a current model Biogon lens. Please inform us what
> the, "drastic differences in optical performance " are. And how were,
> these, "drastic differences", measured?
>
> Incidentally, I own 3- 21mm Zeiss Biogon lenses, purchased in 1960's and
> they are high resolution lenses. I used to shoot twin camera 35mm stereo
> with them, in the 1960's-1970's.
>
> DON
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

On 9/28/11 5:01 PM, Bill G wrote:

> Here are results from Perez for Mamiya 7 80mm lens....>
> 120 120 60 *f/4*
> 120 120 68 *f5.6
> *120 107 68 *f/8*
> 107 107 76 *f/11
> See if you can find any 1950's lenses that are in this league, specially at f4....

OK?

On 8-15 at 4;28 PM, PST bill wrote, "each time you stop down, you
degrade the image quality via aperture diffraction".

>>> I can find no comparative lens test of the M7 43mm and the vintage Zeiss???
>>> Once again, re read my post, I was not questioning the basis of the design... I simple
>>> stated, they had drastic difference in optical performance..... get it?

NO, let us get serious. Having reviewed the previous resolution tests
by Mr C. Perez, I put little faith in his test procedures.

How does anyone take full advantage of a 3d camera taking lens that
resolves 120 lp/mm ?

What color film can anyone buy that will resolve 120 lp/mm ? Please
tell us its name, and where we can buy it.

If, as Mike Davis asserted, the human eye can only resolve 5 lp/mm, it
would require a magnification of 120/5, or about 24X magnification to be
able to see this incredibly high resolution image, A 24X loup would
only cover a very very small image is my assumption, less than a quarter
of an inch square, maybe. What currently available color film is
available that can withstand a magnification of 24X +? Please give us
its name, and where we can buy it!

For what it may be worth, on Aug 16, at 5:39 AM, PST, on photo-3d, we
were told: "To determine resolution, we must discuss the lens being
used, the film type, the DOF being used, shutter speed ...".I don't
believe the C. Perez "test", did give us all of this 'necessary'
information! I have no idea as to what is meant by, "the DOF being used".

Do we need an overkill of resolution in our 3d slides, 35mm or MF ? In
the MF folios, I have seen MF slides, by Chuck Holzner and others that
were sharp enough, that I had to look more than once to try to guess
whether they were taken with a Sputnik or a TL-120, and I was not always
correct. Sometimes, they were taken with a, well tuned, Sputnik.

My experience has been that the Sputnik resolution capabilities do not
go above 30 lp/mm, which, in many cases is more than adequate.

In my opinion the resolution race is similar to the horsepower with cars.

DON

Don, you keep moving the goal posts....
first you mention that there has been no improvements in lens designs since the 50's, then I give you ONE example of a modern lens performance, and you change the topic to, "how does this help in 3d"...  

anyway, this is why I must cease communications with you on this list as well...., its impossible to get anything resolved, as once you receive information which dispute your position you simply change the issue, I made this clear on tech3d, now the same on MF3d.... so I need to close out communications on this list also....  

Wishing you the best of health and happiness....

Bill

On 9/30/2011 6:29 AM, Don Lopp wrote:

On 9/28/11 5:01 PM, Bill G wrote: 

Here are results from Perez for Mamiya 7 80mm lens....> 120 120 60 *f/4* 120 120 68 *f5.6 *120 107 68 *f/8* 107 107 76 *f/11 See if you can find any 1950's lenses that are in this league, specially at f4.... 

  OK?  On 8-15 at 4;28 PM, PST bill wrote, "each time you stop down, you  degrade the image quality via aperture diffraction".  

I can find no comparative lens test of the M7 43mm and the vintage Zeiss??? Once again, re read my post, I was not questioning the basis of the design... I simple stated, they had drastic difference in optical performance..... get it? 

NO, let us get serious.  Having reviewed the previous resolution tests  by Mr C. Perez, I put little faith in his test procedures.  How does anyone take full advantage of a 3d camera taking lens that  resolves 120 lp/mm ?  What color film can anyone buy that will resolve 120 lp/mm ?  Please  tell us its name, and where we can buy it.  If, as Mike Davis asserted, the human eye can only resolve 5 lp/mm, it  would require a magnification of 120/5, or about 24X magnification to be  able to see this incredibly high resolution image,  A 24X loup would  only cover a very very small image is my assumption, less than a quarter  of an inch square, maybe.  What currently available color film is  available that can withstand a magnification of 24X +?  Please give us  its name, and where we can buy it!  For what it may be worth, on Aug 16, at 5:39 AM, PST, on  photo-3d, we  were told: "To determine resolution, we must discuss the lens being  used, the film type, the DOF being used, shutter speed ...".I don't  believe the C. Perez "test", did give us all of this 'necessary'  information!  I have no idea as to what is meant by, "the DOF being used".  Do we need an overkill of resolution in our 3d slides, 35mm or MF ? In  the MF folios, I have seen MF slides, by Chuck Holzner and others that  were sharp enough, that I had to look more than once to try to guess  whether they were taken with a Sputnik or a TL-120, and I was not always  correct.  Sometimes, they were taken with a, well tuned, Sputnik.  My experience has been that the Sputnik resolution capabilities do not  go above 30 lp/mm, which, in many cases is more than adequate.  In my opinion the resolution race is similar to the horsepower with cars.  DON      ------------------------------------  Yahoo! Groups Links  <*> To visit your group on the web, go to:     http://groups.yahoo.com/group/MF3D-group/  <*> Your email settings:     Individual Email | Traditional  <*> To change settings online go to:     http://groups.yahoo.com/group/MF3D-group/join     (Yahoo! ID required)  <*> To change settings via email:     MF3D-group-digest@yahoogroups.com      MF3D-group-fullfeatured@yahoogroups.com  <*> To unsubscribe from this group, send an email to:     MF3D-group-unsubscribe@yahoogroups.com  <*> Your use of Yahoo! Groups is subject to:     http://docs.yahoo.com/info/terms/   

On 9/30/11 8:31 AM, Bill G wrote:

> Don, you keep moving the goal posts....
> first you mention that there has been no improvements in lens designs
> since the 50's, then I give you ONE example of a modern lens
> performance, and you change the topic to, "how does this help in 3d"...

Do me a favor, please tell me when and where I mentioned the ridiculous
statement, "that that there has been no improvements in lens designs
since the 50's...". I did not just fall off of a peach truck.

Also, your example of a modern lens..., I do not know how modern the
80mm Mamiya 7 lens is, considering the fact that the, so called,
'modern' Mamiya 43mm Mamiya 7 lens was designed BY CARL ZEISS, prior to
1954.

I do not beleive that I was changing the subject when I asked, "how does
this help in 3d..." How does an, alleged, resolution of 120 line pairs
per/mm be of any help if the viewer can only resolve less than 35 line
pairs per mm? Again, what is the answer?

A puzzled,

DON

> anyway, this is why I must cease communications with you on this list as
> well...., its impossible to get anything resolved, as once you receive
> information which dispute your position you simply change the issue, I
> made this clear on tech3d, now the same on MF3d.... so I need to close
> out communications on this list also....