On Mon, Sep 26, 2011 at 12:41 PM, Don Lopp <dlopp@rainier-web.com> wrote:

 

Hi:

As of yesterday, I now have what I consider to be a viable, WA MF
viewer, with 45mm fl viewing lenses.

Several years ago I mentioned that I had a constructed a compound, 45mm
fl viewing lens that covered MF 3d slides. Yesterday I put two of them
together, forming a MF 3d viewer, using duct tape and Scotch Tape. Total
cost was less than $ 75, for the 4 achromatic lenses used, 2 from a Good
Will store, the other 2 from a Seattle camera store. All of the lenses
date back 15 or more years, as to their date of manufacture. I will show
the viewer to Bob Venezia so that he can give his appraisal of its
utility in viewing his MF 3d slides, which were shot with 50mm fl
Hasselblad lenses.

I mention this event because I am tired of reading, on the 3d web, about
the advantages of modern optics, over the, allegedly, passe lenses of
the past. Superb Zeiss Tessars and Voigtlander Heliar taking lenses,
have been around for more than 100 years.

Regards,

DON

--
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I will second that.   Optics are based on optical principles that are the same today as they were a hundred years ago.   There are some advantages to modern optics, but they are mainly economic, and to a lesser extent ergonomic.   One of the few differences of lenses made today are the use of aspheric rather than spherical elements for SOME of the elements, and computerized design (mainly ray tracing).  These "advances" have made manufacture less costly (whether this is passed on to the consumer is another debate).  

                                             JR,  I know a slew of optical design engineers that would disagree with this assessment.    Matter of fact, I don't know any who would agree.   Computers have revolutionized every field, specially optical design in which design time has been slashed by factors of 50x.   This enables BETTER designs today than in yesteryear....  there is also better glass, and better glass manufacturing technology as well as coatings.   In many cases, the added elements increases the cost of the lenses.   Look at Canons long offerings, some lenses are $8k.    They are producing better long fl lenses today than even 5-10 years ago, breakthroughs continue.....  I think people who make these comments never use these modern lenses.... 

It has, in some cases, resulted in the use of less elements for similar (though not necessarily equal) optical performance.  As a result slightly shorter lens barrels with slightly less weight are now possible.   In theory, modern lenses should be more consistent due to supposedly more uniform manufacturing techniques.   I have not seen any numbers to support this in practice, but it does have some logic.  

Are newer lenses better or worse than older ones?   The jury is still out.   Certainly most of the specifications as well as actual test results of the lenses that Don cites, as well as many others, equal or exceed those of many of the modern "replacements". 

                                              Look at a few of the Canon MTF curves, show me a lens made 50 years ago that matches any of these longer fl's.   I only pick the long focal lengths because they have improved in larger increments.... and its not just MTF curves.    Its real world testing....

I have tested some of these lenses against new, modern, APO diffraction limited telescopes with the same apertures, and the Canon lenses have matched, and in some cases produced higher resolution......

Anyway, I hate to suckered into this discussion again..... maybe its better to dump all the lenses I have tested and confirmed and grab some 100 year old triplets and shoot with them  :-)

following this same train of thought..... I assume film from the 1940's is also better or as good as our films today?  

Bill

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On Mon, Sep 26, 2011 at 3:48 PM, Bill G <bglick@rconnects.com> wrote:

 

                                             JR,  I know a slew of optical design engineers that would disagree with this assessment.   

Probably.
 

Matter of fact, I don't know any who would agree.  

Possibly.
 

Computers have revolutionized every field, specially optical design in which design time has been slashed by factors of 50x.  

Absolutely.   This has, as I mentioned, reduced manufacture costs considerably.
 

This enables BETTER designs today than in yesteryear.... 

Enables, yes.   Whether this has been realized is not supported by the evidence (actual use).   Part of this depends on the criteria used to determine "better".    Certainly, more efficient design and manufacture for shorter manufacture times and lower costs may be considered better, as I pointed out.
 

there is also better glass, and better glass manufacturing technology as well as coatings.  

Most optical glass used today is not that different from glass available fifty or more years ago.  BK7 and many other formulations are still the same.   Rare earth glasses, such as used in the Voigtlander Apo Lanthar from the 1950's are still used in many modern lenses today.   When multicoating was introduced (many years ago, I don't recall the exact year), there were debates as to how much better this was than single MgF coatings.  In other words, whether the improvement was significant enough to warrant the added cost.   Modern coating methods have reduced the manufacturing costs considerably, but they are still very similar.  
 

In many cases, the added elements increases the cost of the lenses.   Look at Canons long offerings, some lenses are $8k.    They are producing better long fl lenses today than even 5-10 years ago, breakthroughs continue..... 

Yes, breakthroughs continue.   But, in recent years most of these breakthroughs have been in the area of cost-effectiveness.

Better for some things, not as good for others.   In any case, the differences are not as much as the advertising would lead you to believe.
 

I think people who make these comments never use these modern lenses.... 

I use modern lenses all the time.  Zeiss master primes are excellent, and I use them on productions whenever the budget warrants it.   But, they are not as suitable for most stereoscopic applications as other, often older designs.    The smaller form factor of some of the Nikon and Canon lenses (both modern and older) often makes them much more useful, especially for digital cameras.  

following this same train of thought..... I assume film from the 1940's is also better or as good as our films today?  

Another apples-and-oranges comparison.   Film, in my opinion, has advanced much more in recent years than general purpose lenses.   "Modern" lenses designed for the MF and LF image sizes are really not that much better in terms of performance than similar lenses from the post war era.  They may be better in terms of ergonomics and control (motor drives, remotes, etc.).   Note some of the comments of several professional photographers in this group:

http://www.largeformatphotography.info/forum/showthread.php?t=40619

 

JR

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Computers have revolutionized every field, specially optical design in which design time has been slashed by factors of 50x.  

Absolutely.   This has, as I mentioned, reduced manufacture costs considerably.

                                     AND, it enables companies to push for better optical performance in the design.   The old adage in lens design was, you get the performance characteristics you can afford.   Meaning, a $300k design fee for a lens will greatly outperform a $30k design fee.... this is the nature of optical design, I learned this the hard way.... of course, there is applications where simple designs meet the design requirements, but today, with high resolution recording sensors, optics designs are being pushed to the limits....

 

This enables BETTER designs today than in yesteryear.... 

Enables, yes.   Whether this has been realized is not supported by the evidence (actual use). 

                               I gave several examples....   Its possible in the cinema field, this is not the case, but in photographic lenses, the differences are quite dramatic in many areas, but most noticeable in the long fl's. 

Part of this depends on the criteria used to determine "better".    Certainly, more efficient design and manufacture for shorter manufacture times and lower costs may be considered better, as I pointed out.

                                    Quite the opposite in my examples...... more complex designs, both optically and opto-mechanically, which is increasing lens cost, not decreasing.  But, you attain better performance characteristics.     However, I am not disputing your position as well, on the low end, better design capabilities are enabling more cost effective designs, as you correctly point out, aspherics alone has drastically changed how lens desingers think about design.... so in many cases, less elements is possible AND lower tolerances is possible.   We see this with many of the "kit" lenses that come with the DSLR's.... they are practically give-away lenses, such as 18-55mm zooms, and yet, their performance is surprisingly good....
 

 

there is also better glass, and better glass manufacturing technology as well as coatings.  

Most optical glass used today is not that different from glass available fifty or more years ago.

                                     Well, this discussion jumps from 50 years ago, to 100 years ago, .....  there was less changes vs. 50 years ago vs. 100 years ago, as another poster always refers to "turn of the century" lenses being as good as anything produced today....

 

In many cases, the added elements increases the cost of the lenses.   Look at Canons long offerings, some lenses are $8k.    They are producing better long fl lenses today than even 5-10 years ago, breakthroughs continue..... 

Yes, breakthroughs continue.   But, in recent years most of these breakthroughs have been in the area of cost-effectiveness.

 
                                              I see it at both ends....not just the cost effective end.  

Better for some things, not as good for others.   In any case, the differences are not as much as the advertising would lead you to believe.
 

I think people who make these comments never use these modern lenses.... 

I use modern lenses all the time.  Zeiss master primes are excellent, and I use them on productions whenever the budget warrants it.   But, they are not as suitable for most stereoscopic applications as other, often older designs.    The smaller form factor of some of the Nikon and Canon lenses (both modern and older) often makes them much more useful, especially for digital cameras.  

                                My comments revolve only around photographic lenses, I know your background is strong in cinema....  so sometimes we might be commenting on different beasts....I doubt in cinema you are using a 400mm f4.0 lens... 

following this same train of thought..... I assume film from the 1940's is also better or as good as our films today?  

Another apples-and-oranges comparison.   Film, in my opinion, has advanced much more in recent years than general purpose lenses.   "Modern" lenses designed for the MF and LF image sizes are really not that much better in terms of performance than similar lenses from the post war era.  They may be better in terms of ergonomics and control (motor drives, remotes, etc.).   Note some of the comments of several professional photographers in this group:

                                  If you look at the MTF data on the new Schneider LF lenses, such as Super Symar XL, the performance increases are stunning vs. post war LF lenses.  I have tested many of these and simply do not buy this notion. 

Have a look at the performance of the MODERN Mamiya 7 lenses vs. some of the older 70's - 80's MF lenses, then let me know if you still buy into the fact lens performance has not increased dramatically.....  finding a comment a person writes on a forum is rarely credible, specially in the field of optics... let me know your thoughts after you review these test results....

http://www.hevanet.com/cperez/MF_testing.html


Bill

http://www.largeformatphotography.info/forum/showthread.php?t=40619

 

JR

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On Sep 26, 2011, at 12:41 PM, Don Lopp wrote:

>
> Hi:
>
> As of yesterday, I now have what I consider to be a viable, WA MF
> viewer, with 45mm fl viewing lenses.
>
> Several years ago I mentioned that I had a constructed a compound,
> 45mm
> fl viewing lens that covered MF 3d slides. Yesterday I put two of them
> together, forming a MF 3d viewer, using duct tape and Scotch Tape.
> Total
> cost was less than $ 75, for the 4 achromatic lenses used, 2 from a
> Good
> Will store, the other 2 from a Seattle camera store. All of the lenses
> date back 15 or more years, as to their date of manufacture. I will
> show
> the viewer to Bob Venezia so that he can give his appraisal of its
> utility in viewing his MF 3d slides, which were shot with 50mm fl
> Hasselblad lenses.
>
> I mention this event because I am tired of reading, on the 3d web,
> about
> the advantages of modern optics, over the, allegedly, passe lenses of
> the past. Superb Zeiss Tessars and Voigtlander Heliar taking lenses,
> have been around for more than 100 years.
>
> Regards,
>
> DON

On Tue, Sep 27, 2011 at 5:02 AM, Bill G <bglick@rconnects.com> wrote:

 

Computers have revolutionized every field, specially optical design in which design time has been slashed by factors of 50x.  

Absolutely.   This has, as I mentioned, reduced manufacture costs considerably.

                                     AND, it enables companies to push for better optical performance in the design.   The old adage in lens design was, you get the performance characteristics you can afford.   Meaning, a $300k design fee for a lens will greatly outperform a $30k design fee.... this is the nature of optical design, I learned this the hard way.... of course, there is applications where simple designs meet the design requirements, but today, with high resolution recording sensors, optics designs are being pushed to the limits....

 

This enables BETTER designs today than in yesteryear.... 

Enables, yes.   Whether this has been realized is not supported by the evidence (actual use). 

                               I gave several examples....   Its possible in the cinema field, this is not the case, but in photographic lenses, the differences are quite dramatic in many areas, but most noticeable in the long fl's. 

Part of this depends on the criteria used to determine "better".    Certainly, more efficient design and manufacture for shorter manufacture times and lower costs may be considered better, as I pointed out.

                                    Quite the opposite in my examples...... more complex designs, both optically and opto-mechanically, which is increasing lens cost, not decreasing.  But, you attain better performance characteristics.     However, I am not disputing your position as well, on the low end, better design capabilities are enabling more cost effective designs, as you correctly point out, aspherics alone has drastically changed how lens desingers think about design.... so in many cases, less elements is possible AND lower tolerances is possible.   We see this with many of the "kit" lenses that come with the DSLR's.... they are practically give-away lenses, such as 18-55mm zooms, and yet, their performance is surprisingly good....

 

 

there is also better glass, and better glass manufacturing technology as well as coatings.  

Most optical glass used today is not that different from glass available fifty or more years ago.

                                     Well, this discussion jumps from 50 years ago, to 100 years ago, .....  there was less changes vs. 50 years ago vs. 100 years ago, as another poster always refers to "turn of the century" lenses being as good as anything produced today....

 

In many cases, the added elements increases the cost of the lenses.   Look at Canons long offerings, some lenses are $8k.    They are producing better long fl lenses today than even 5-10 years ago, breakthroughs continue..... 

Yes, breakthroughs continue.   But, in recent years most of these breakthroughs have been in the area of cost-effectiveness.

 

                                              I see it at both ends....not just the cost effective end.  

Better for some things, not as good for others.   In any case, the differences are not as much as the advertising would lead you to believe.
 

I think people who make these comments never use these modern lenses.... 

I use modern lenses all the time.  Zeiss master primes are excellent, and I use them on productions whenever the budget warrants it.   But, they are not as suitable for most stereoscopic applications as other, often older designs.    The smaller form factor of some of the Nikon and Canon lenses (both modern and older) often makes them much more useful, especially for digital cameras.  

                                My comments revolve only around photographic lenses, I know your background is strong in cinema....  so sometimes we might be commenting on different beasts....I doubt in cinema you are using a 400mm f4.0 lens... 

following this same train of thought..... I assume film from the 1940's is also better or as good as our films today?  

Another apples-and-oranges comparison.   Film, in my opinion, has advanced much more in recent years than general purpose lenses.   "Modern" lenses designed for the MF and LF image sizes are really not that much better in terms of performance than similar lenses from the post war era.  They may be better in terms of ergonomics and control (motor drives, remotes, etc.).   Note some of the comments of several professional photographers in this group:

                                  If you look at the MTF data on the new Schneider LF lenses, such as Super Symar XL, the performance increases are stunning vs. post war LF lenses.  I have tested many of these and simply do not buy this notion. 

Have a look at the performance of the MODERN Mamiya 7 lenses vs. some of the older 70's - 80's MF lenses, then let me know if you still buy into the fact lens performance has not increased dramatically.....  finding a comment a person writes on a forum is rarely credible, specially in the field of optics... let me know your thoughts after you review these test results....

http://www.hevanet.com/cperez/MF_testing.html


Bill

http://www.largeformatphotography.info/forum/showthread.php?t=40619

 

JR

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On 9/27/2011 9:32 AM, Bob Venezia wrote:
>
> Last night I had the pleasure of visiting with Don Lopp and seeing his
> new viewer. Don had called me a couple times to tell me he thought his
> new viewer was "pretty good," and when Don says something is pretty
> good I know to pay attention. Don asked me to bring along some of my
> Hasselblad slides shot with the 50mm lenses but also wanted to see a
> recent fireworks hyper taken with 150mm lenses and 20' separation.
>
> For years I've been hearing folks talk about matching focal lengths of
> the viewing lenses and taking lenses but I've never paid that much
> mind as I'm clam-happy with my cameras and lenses and Sam Smith Regal
> viewer.
>
> After last night all I can say is, "oh my god." The images are so
> large and immersive it's unbelievable. Two shots in particular really
> stood out. Both are hypers. One was shot with the Hasselblads and 50mm
> lenses at Bryce Canyon overlooking a trail. Cameras were probably 1
> foot apart. At the time I was cursing all the photographers that were
> on the trail with their tripods sullying my shot. Of course it turns
> out that they make the shot and give a sense of scale. This shot had
> fantastic depth and clarity in Don's viewer. It was already an
> "audience favorite" but I'd never seen it like this before.
>
> But even the fireworks, taken with the 150mm lenses, were stunning in
> Don's viewer. You felt you were inside the fireworks.
>
> Everything else was simply amazing.
>
> And apparently Don built the thing out of a thrift store pair of
> binoculars and 2 old loupes he had laying around. I asked if they were
> really great loupes and Don said, "not particularly," though with Don
> I don't know if that means they cost $800 or $20 @.
>
> Anyone who has a chance should make a pilgrimage to Des Moines (WA) to
> see this thing!
>
> cheers,
> Bob Venezia
> Seattle, Washington
>
> On Sep 26, 2011, at 12:41 PM, Don Lopp wrote:
>
> >
> > Hi:
> >
> > As of yesterday, I now have what I consider to be a viable, WA MF
> > viewer, with 45mm fl viewing lenses.
> >
> > Several years ago I mentioned that I had a constructed a compound,
> > 45mm
> > fl viewing lens that covered MF 3d slides. Yesterday I put two of them
> > together, forming a MF 3d viewer, using duct tape and Scotch Tape.
> > Total
> > cost was less than $ 75, for the 4 achromatic lenses used, 2 from a
> > Good
> > Will store, the other 2 from a Seattle camera store. All of the lenses
> > date back 15 or more years, as to their date of manufacture. I will
> > show
> > the viewer to Bob Venezia so that he can give his appraisal of its
> > utility in viewing his MF 3d slides, which were shot with 50mm fl
> > Hasselblad lenses.
> >
> > I mention this event because I am tired of reading, on the 3d web,
> > about
> > the advantages of modern optics, over the, allegedly, passe lenses of
> > the past. Superb Zeiss Tessars and Voigtlander Heliar taking lenses,
> > have been around for more than 100 years.
> >
> > Regards,
> >
> > DON
>
>

> Bob, thx for report....
>
> Immersive means different things to different people :-)
>
> what fl were the viewing lenses?
> or what was the HFOV in degrees?

> Bob, thx for report....
>
> Immersive means different things to different people :-)
>
> what fl were the viewing lenses?
> or what was the HFOV in degrees?
>
> trying to better understand what you were looking at...
>
> Bill G
>
>
> On 9/27/2011 9:32 AM, Bob Venezia wrote:
> >
> > Last night I had the pleasure of visiting with Don Lopp and seeing
> his
> > new viewer. Don had called me a couple times to tell me he thought
> his
> > new viewer was "pretty good," and when Don says something is pretty
> > good I know to pay attention. Don asked me to bring along some of my
> > Hasselblad slides shot with the 50mm lenses but also wanted to see a
> > recent fireworks hyper taken with 150mm lenses and 20' separation.
> >
> > For years I've been hearing folks talk about matching focal lengths
> of
> > the viewing lenses and taking lenses but I've never paid that much
> > mind as I'm clam-happy with my cameras and lenses and Sam Smith Regal
> > viewer.
> >
> > After last night all I can say is, "oh my god." The images are so
> > large and immersive it's unbelievable. Two shots in particular really
> > stood out. Both are hypers. One was shot with the Hasselblads and
> 50mm
> > lenses at Bryce Canyon overlooking a trail. Cameras were probably 1
> > foot apart. At the time I was cursing all the photographers that were
> > on the trail with their tripods sullying my shot. Of course it turns
> > out that they make the shot and give a sense of scale. This shot had
> > fantastic depth and clarity in Don's viewer. It was already an
> > "audience favorite" but I'd never seen it like this before.
> >
> > But even the fireworks, taken with the 150mm lenses, were stunning in
> > Don's viewer. You felt you were inside the fireworks.
> >
> > Everything else was simply amazing.
> >
> > And apparently Don built the thing out of a thrift store pair of
> > binoculars and 2 old loupes he had laying around. I asked if they
> were
> > really great loupes and Don said, "not particularly," though with Don
> > I don't know if that means they cost $800 or $20 @.
> >
> > Anyone who has a chance should make a pilgrimage to Des Moines (WA)
> to
> > see this thing!
> >
> > cheers,
> > Bob Venezia
> > Seattle, Washington
> >
> > On Sep 26, 2011, at 12:41 PM, Don Lopp wrote:
> >
> > >
> > > Hi:
> > >
> > > As of yesterday, I now have what I consider to be a viable, WA MF
> > > viewer, with 45mm fl viewing lenses.
> > >
> > > Several years ago I mentioned that I had a constructed a compound,
> > > 45mm
> > > fl viewing lens that covered MF 3d slides. Yesterday I put two of
> them
> > > together, forming a MF 3d viewer, using duct tape and Scotch Tape.
> > > Total
> > > cost was less than $ 75, for the 4 achromatic lenses used, 2 from a
> > > Good
> > > Will store, the other 2 from a Seattle camera store. All of the
> lenses
> > > date back 15 or more years, as to their date of manufacture. I will
> > > show
> > > the viewer to Bob Venezia so that he can give his appraisal of its
> > > utility in viewing his MF 3d slides, which were shot with 50mm fl
> > > Hasselblad lenses.
> > >
> > > I mention this event because I am tired of reading, on the 3d web,
> > > about
> > > the advantages of modern optics, over the, allegedly, passe lenses
> of
> > > the past. Superb Zeiss Tessars and Voigtlander Heliar taking
> lenses,
> > > have been around for more than 100 years.
> > >
> > > Regards,
> > >
> > > DON
> >
> >
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

> the century" lenses being as good as anything produced today..."

> Have a look at the performance of the MODERN Mamiya 7 lenses vs. some of
> the older 70's - 80's MF lenses, then let me know if you still buy into
> the fact lens performance has not increased dramatically... let me know your thoughts after you review these test
> results....

> http://www.hevanet.com/cperez/MF_testing.html

>> Have a look at the performance of the MODERN Mamiya 7 lenses vs. some of
>> the older 70's - 80's MF lenses, then let me know if you still buy into
>> the fact lens performance has not increased dramatically... let me know your thoughts after you review these test
>> results....
>> http://www.hevanet.com/cperez/MF_testing.html
> IMO, this URL presents an example of flawed science.

--- In MF3D-group@yahoogroups.com, Bob Venezia wrote:
>
> Last night I had the pleasure of visiting with Don Lopp and seeing his
> new viewer. Don had called me a couple times to tell me he thought his
> new viewer was "pretty good," and when Don says something is pretty
> good I know to pay attention.

--- In MF3D-group@yahoogroups.com, "Don" wrote:
>
> I want to second what Bob says here. I saw a slide in the viewer at our club meeting, and it was excellent. "Immersive" is the perfect word for it. The field of view was very wide and the sense of "being there" was high. You could barely see the edges of the slide by looking all the way to the right or left. It really makes the window essentially unimportant, because the edges of the image almost don't register in your visual field. I've seen the same effect when watching IMAX.
>
> I'm not sure every image would be right for this viewer, but the sense of being *in* the scene rather than looking *at* the scene was one that I'd gladly love to experience more of.
>
> Don
>
> --- In MF3D-group@yahoogroups.com, Bob Venezia wrote:
> >
> > Last night I had the pleasure of visiting with Don Lopp and seeing his
> > new viewer. Don had called me a couple times to tell me he thought his
> > new viewer was "pretty good," and when Don says something is pretty
> > good I know to pay attention.
>

--- In MF3D-group@yahoogroups.com, "lattie_smart" wrote:
>
> I guess I'm too impatient to read this whole thread thoroughly. :-)
>
> Speaking as a glasses wearer, what is the lenses diameter?
>
> Could the source optics, or equivalents, possibly still be dredged ...maybe up on eBay?
> (or will this remain a proprietary house recipe?) :-)
>
> It would be lovely if one such (heavily insured) viewer was routed with some of the MF folios...
>
>

On Oct 11, 2011, at 2:06 PM, Matt Neima wrote:
> I looked at MF views with one of Don's viewers at an NSA convention
> in Buffalo, it was the best (and sorry, the ugliest) viewer I've
> ever used.
>
>
> Don, if the recipe is available for this immersive viewer I am also
> interested in hearing it.
>
> Matt
>
> --- In MF3D-group@yahoogroups.com, "lattie_smart"
> wrote:
> >
> > I guess I'm too impatient to read this whole thread thoroughly. :-)
> >
> > Speaking as a glasses wearer, what is the lenses diameter?
> >
> > Could the source optics, or equivalents, possibly still be
> dredged ...maybe up on eBay?
> > (or will this remain a proprietary house recipe?) :-)
> >
> > It would be lovely if one such (heavily insured) viewer was routed
> with some of the MF folios...
>