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Subject: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-23 00:55:41
From: Don Lopp

-------- Original Message --------

Subject:	Re: [MF3D-group] Design fault in the 3d World system
Date:	Fri, 22 Aug 2014 23:24:24 -0700
From:	Don Lopp
To:	MF3D-group@yahoogroups.com

On 8/21/2014 12:48 AM, jean-paul.nivoix@laposte.net [MF3D-group] wrote:

>particularly the 3D World STL viewer, the 3D World illuminated viewer,
>and the 3D World mounting jig.
>This is non-sense, and a terrible design fault from 3D World.

In defense of 3D Worlds' decision to use 75mm fl viewer lenses. The 75mm fl lenses were installed in their many STL and many rotary viewers many years before the TL 120 camera was put into production. My guess is that they mass produced many, many thousands of these 75mm fl viewer lenses, intended for future use. These 75mm lenses are well designed, with a flat field combined with low distortion, and probably a low production cost. Considering the high quality of the 80mm fl taking lens, l assume that they purchased the 80mm lens as it was available, not wanting go through the costly expense of re=tooling to manufacture a relatively small quantity of 75mm fl lenses. I would have preferred that they had chosen a more modest f/3.5 or slower lens so as to lower the cameras weight. Every thing considered, we have been very fortunate to have had the opportunity to purchase the TL 120, as it was presented, with its extremely high resolution lenses. Can you imagine how much those lenses would have cost if Hasselblad or C. Zeiss were selling them? Don't forget, there are many more 75mm fl lensed 3D cameras in use by the 3D community, than TL 120s'. They include the Rolleidoscop, the Heidoscop and the many, many Sputniks. 3D World should get credit for their uniqe TL 120 shutter design, using a pair of SLR Copal type shutters, which helped to reduce the overall manufacturing costs.

John Thurston could probably tell us if the 3D World viewer has enough focus travel to accept 80mm fl lenses, but I have my doubts. The MF viewers made by Sam Smith contain either 80mm or 84mm lenses is my understanding. I have never heard any complaints about their fl, just compliments about their overall optical quality. the Saturn MF viewers contained 78mm and 85mm fl lenses. I have never heard of any complaints regarding their non Ortho viewing.

I am interested as to why you used a Sputnik camera, with its lower optical quality lenses, to test the fl difference between its 75mm lenses and the TL 120s' 80mm taking lenses, regarding the questionable benifits of maintaining "Ortho" viewing. I think it would have been a more fair test if you had used either a Rolleidoscop or a Heidoscop, both available in Europe, as their Carl Zeiss lenses offer a much hgher overall resolution than do the majority of the Sputnik lenses that I have seen.

Cheers,

DON

Cheers,

DON

>Indeed, rather than choosing 75 mm for the viewing lenses,
>the mistake was to escape from ortho-stereocopic conditions
>by selecting 80 mm taking lenses for the 3D World TL120 camera.
>What we should be aiming at, now, would be to save the pictures
>taken with this camera
>by looking at them in a 80 mm stereoscope.

Helo Jean Paul,

>This way, the depth in our TL120 images would not be flattened
>as it is right now.
>While losing a little bit of immersion
>(which the TL120 images in a 75 mm viewer have a lot, probably too much),
>we could recover the complete (nothing more, nothing less)
>third dimension which we are looking after.

J-Paul

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-23 06:40:51
From: jpnivoix

Thank you very much for your complete answer, with an interesting guess of what 3D World dilemma may have been.I didn't know they were selling MF viewers (etc ...) before introducing TL120.
But as you pointed out, it was sure a good choice to view with 75 mm lenses
(compatibility with almost all MF cameras of the past).

The real fault (according to me) even worse than escaping from orto-stereocopic conditions
was to select these 80 mm superb lenses with wide opening
... which are so heavy and make the camera unbalanced :
the advantage of f:2,8 is null in stereo-photography
and the 80 mm focal length a penalization for depth of field.
This remark has been made several years ago by the late Chuck Holzner.

Let me just come back for a second about flattened images :
I admit that, for a better evaluation of how much visual depth we're losing
(watching a picture taken with TL120 in a 75 mm fl stereoscope)
one should compare two pictures taken at the same place,
and at the same time, with a Spud and a TL120.
And not compare a bunch of photos with another bunch of photos.
This I'll do one of these days and if you want I'll keep you informed.

To finish my answer, I want to emphasize that the Spoutnik is far from obsolete
even compared to the TL120 with its sharp lenses.
And I'm going to continue using it a lot for :
       - its lightweight : 800 g against 2060g for TL120 !!
       - its high compacity
       - its perfect equilibrium (inertia/center of gravity)
       - its high depth of field (not only due to fl 75, also f:22+1/3 instead of f:22)
       - when used at f:22+1/3, optical quality not so bad
       - its wider angle and better fitment with 75 mm fl stereoscopes (no loss in depth at all)
       - no batteries needed
       - nice bakelite object from the past instead of ugly modern plastic
       - easy to find (85,000 made) easy to replace, even some pare parts available from Lubitel
       - etc ...

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-25 23:56:24
From: jpnivoix

(To Don Lopp)in your above message you asked the following

I am interested as to why you used a Sputnik camera, with its lower optical quality lenses, to test the fl difference between its 75mm lenses and the TL 120s' 80mm taking lenses, regarding the questionable benifits of maintaining "Ortho" viewing. I think it would have been a more fair test if you had used either a Rolleidoscop or a Heidoscop, both available in Europe, as their Carl Zeiss lenses offer a much hgher overall resolution than do the majority of the Sputnik lenses that I have seen.

I'm afraid that my reply (why I continue to use Spoutnik, lightweight, compacity etc ...)
was not relevant.

It seems that the concern you raise is about limited accuracy of the Spoutnik lenses
being unsuitable for the judgement of non-ortho stereoscopy.
So here is my (better) answer :

1/ to distinguish distorted images or even "Gulliver effect" / model effect (I'm not sure which expression to use in english for "effet de maquette")
you don't need accurate stereo images : even on a TV screen this is perfectly visible

2/ More generally, there is a debate going on about "stereoscopic resolution (or sharpness)
and its relation with resolution on the film".
Many believe that unless you have a very high resolution on each of the 2D images,
you will not have the best stereoscopic resolution.
And this point of view tends to highlight the TL120 lenses as a major advantage
compared to Spoutnik -> Spud much inferior in terms of 3D effect ...

On the contrary, some experts in 3D theory, like Olivier Cahen, a french stereoscopist
known for his book " L'image en relief " which was recently re-printed
claim that this analysis is wrong - or at least incomplete.
What they say is that the analysis of eye convergence to explain parallax effects
does not reflect all the human ability to perceive depth - even when you restrict to binocular depth. The brain has a capacity to give accurate depth information even from 2 "poor" resolution images.
"Poor" meaning poorer than the usual calculation "line pairs + enlarging factor + angular visual accuracy" gives.
This fact is proven from experience, including research done by the IGN,
a world famous cartographer institute.

When I speak of "stereoscopic vision accuracy", sorry if this is not the proper word,
I mean "ability to distinguish two objects in depth".

So if I rely on Olivier Cahen, the Spoutnik is able to produce extremely high and accurate
binocular 3D effect, despite its relatively poor optics.
And anyway, I think that it will not be a limitation to judge distortion
between its 75 mm taking lenses and the TL120 80 mm taking lenses.

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-30 17:52:20
From: coronet3d

I wasn't able to read Don's message but regarding the Sputnik's lenses, IMO, there is a greater improvement in image quality from using a camera (Sputnik or otherwise) handheld vs on a tripod than the difference between a three element lens, like the T22, and a four element lens. When stopped down the differences between 3 and 4 element lenses nearly evaporate (although some 3 element lenses might vignette depending on the focal length). The bigger problems with the Sputnik have to do with the body's design, e.g. light leaks, internal reflections, etc. than the lenses. The Lubitel has been a popular camera for years and still has a cult following.

STeve

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-30 21:46:36
From: Don Lopp

On 8/30/2014 4:52 PM, coronet3d@yahoo.com [MF3D-group] wrote:

I wasn't able to read Don's message but regarding the Sputnik's lenses, IMO, there is a greater improvement in image quality from using a camera (Sputnik or otherwise) handheld vs on a tripod than the difference between a three element lens, like the T22, and a four element lens. When stopped down the differences between 3 and 4 element lenses nearly evaporate (although some 3 element lenses might vignette depending on the focal length). The bigger problems with the Sputnik have to do with the body's design, e.g. light leaks, internal reflections, etc. than the lenses. The Lubitel has been a popular camera for years and still has a cult following.

STeve

Hello Steve,

You have surprised me, as you, apparently, suspect that anyone would test a camera lens when the camera is not on a tripod? ALL of my test of camera lenses for resolution, since 1950, have been performed on a tripod! The 4 element Yashinon lens on the Yashica 2 1/4 TLR cameras easily (at f/11) out perform any of the 20 plus Sputniks that I have worked on, even at f/16-f/22, when Fuji Velvia was used. With the Sputnik at f/11, the off center astigmatism is easily observed. Stopping the Sputnik lens down to f/16-f/22 is the only way to get a reasonably sharp image in a Sputnik, though not in the corners. Hopefully, both the Sputnik lenses has been tuned to be in true focus, as I have never seen a Sputnik that did not need both of its lenses adjusted so as to be in true focus. You did neglect to indicate which 4 element lenses that you were comparing the Sputnik lenses with.

>"When stopped down the difference between 3 and 4 element lenses nearly evaporate."

I do not agree, as after testing many cameras with 3 element and 4 element lenses, I have never tested a 3 element lens, (including the Zeiss Novar and Triotar plus the Voigtlander Voigtar lenses),even when stopped down that was comparable to most 4 element lenses. At best, were only comparable with the second rate f/2.8 4 element Zeiss Tessar lenses which were eagerly replaced, in the 1960s' by the Zeiss Planar f/3.5 and f/2.8 lenses. I remember the Rollie ads which did mention the great improvements to be expected if one were to dump their f/2.8 Tessar lensed Rollei cameras.

Is it possible that you are viewing your Sputnik slides on inferior film, or in a less than first class MF viewer?

Cheers,

DON

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-31 09:45:48
From: Don Lopp

On 8/30/2014 4:52 PM, coronet3d@yahoo.com [MF3D-group] wrote:

>"When stopped down the differences between 3 and 4 element lenses nearly evaporate (although some 3 element lenses might vignette depending on the focal length). The bigger problems with the Sputnik have to do with the body's design, e.g. light leaks, internal reflections, etc. than the lenses. The Lubitel has been a popular camera for years and still has a cult following."

Hello Steve,
    Have you noticed that the, 30 + year old Sputniks' attempt to position their lens elements in their proper position by using split rings, instead of by using threaded rings? They were just asking for trouble, IMO.
    The elimination of light leaks and the elimination of internal reflections are both easily fixed problems but fixing Sputnik lens problems is not so easy, for most of the 3D community members, is my assessment.

   > "although some 3 element lenses might vignette depending on the focal length."
What does the fl have to do with their vignetting problem?

Cheers,

DON

STeve

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-31 11:05:00
From: coronet3d

Is anybody else having trouble reading Don's messages? When I click on them I get a blank box.

Thanks,

Steve

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-31 14:27:25
From: jpnivoix

what I do is click on "Show message history"
and Don Lopp's text appears.

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-31 19:58:52
From: coronet3d

My point was that by using a tripod you get a larger performance improvement than by switching from a 3 to 4 element lens. I'll admit that the Sputnik lenses do distort somewhat. I'm sure the 3D World camera was superior but it was much more expensive and from what I've read here there is virtually no repair support for the camera. The Rolleidoscop used uncoated Tessars and is also more expensive than the Sputnik. The Sputnik is the best value for money hands down IMO. I stop down most of the time to f16 and f22. Unfortunately as both E200 and 400X have been discontinued, I may not be able to follow that protocol for too much longer.

Steve

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-08-31 21:14:43
From: jpnivoix

This discussion seems more and more interesting to me, gentlemen.

I would say first that if we wanted to refocus the debate on the original concern
"Design flaw in the 3D World system"
the question of stereoscopic resolution (and even, optical resolution of the lenses)
is not relevant for judging ortho-stereocopy and stretched or flattened images.

My previous message (message n°3, dated Aug. 26th)
where I gave details about this statement, did not raise any argument, unfortunately.
Does this mean all of you agree ? I doubt it ;-)

But second, if we agree to extend the question to
"how much inferior is Sputnik to TL120, with its simple optics"
as Coronet3D does brillantly ...
I have a few remarks to go even further :

- Sputnik lenses may distort a bit ... but yes, as it has to be used at f:16 or better f:22
or even further, there is a terrible vignetage flaw
- there are other weaknesses in Sputnik optics, but in reality, the main dilemma in MF 3D photography does not lie in intrinsic optical quality, it is what Coronet3D pointed out :
you need the highest depth of field, in contradiction with the natural focal length of medium format / consequently you are using small lens aperture and low shutter speed / so the main ennemy when taking pictures is camera shake, producing motion blur which will ruin all efforts to high quality images / one solution is high speed films ... but they produce grain which will be visible due to stereoscope high magnification :-((

- Sputnik has a very good feature, regarding this dilemma, from my point of view :
the central lenses shutters (with perfect and simple synchro), resulting in very low vibration.
This combines with camera lightweight, which gives a better resistance to the movement of your body if you are not using a tripod.
Here is another important superiority wrt TL120, apart from smaller focal length and smaller minimum aperture (practically f22+1/3 against f:22).

- by the way, I bought 220 rolls of Provia 400X, because I had the chance to get informed of Fuji's decision to stop production and I could buy the last stocks from some internet retailers.
For portrait photography, where even the fine grain of 400X is quite embarrassing,
I will use Provia 100F ... on a tripod (or a monopod ?).
And if one day I run out of Provia 400X, I'll switch to black and white 400 ISO ...

- last but not least :-( there is actually no more repair support for TL120.
3D world technicians disappeared, they no longer work for the company.
The last time I had my TL120 repaired by 3D World (shutter problem) was in june 2012.
In august 2013 it was absolutely impossible to get any service or technical data from 3D World,
despite their good will. And no independant technician in France or the US will be able to help, due to the lack of any spare parts and lack of technical information ...

Subject: Re: Design fault in the 3d World system
Date: 2014-09-01 07:10:31
From: Timo Puhakka

On 31-Aug-14, at 11:14 PM, jean-paul.nivoix@laposte.net [MF3D-group] wrote:

This discussion seems more and more interesting to me, gentlemen.

I would say first that if we wanted to refocus the debate on the original concern
"Design flaw in the 3D World system"
the question of stereoscopic resolution (and even, optical resolution of the lenses)
is not relevant for judging ortho-stereocopy and stretched or flattened images.

My previous message (message n°3, dated Aug. 26th)
where I gave details about this statement, did not raise any argument, unfortunately.
Does this mean all of you agree ? I doubt it ;-)

I don't see any of this flattening or stretching and have no interest in looking for it. I don't want to spoil my MF experience by looking for flaws that are not self evident.

But second, if we agree to extend the question to
"how much inferior is Sputnik to TL120, with its simple optics"
as Coronet3D does brillantly ...
I have a few remarks to go even further :

- Sputnik lenses may distort a bit ... but yes, as it has to be used at f:16 or better f:22
or even further, there is a terrible vignetage flaw
- there are other weaknesses in Sputnik optics, but in reality, the main dilemma in MF 3D photography does not lie in intrinsic optical quality, it is what Coronet3D pointed out :
you need the highest depth of field, in contradiction with the natural focal length of medium format / consequently you are using small lens aperture and low shutter speed / so the main ennemy when taking pictures is camera shake, producing motion blur which will ruin all efforts to high quality images / one solution is high speed films ... but they produce grain which will be visible due to stereoscope high magnification :-((

I can't tell the difference between some of my Sputnik shots and my TL120. In other cases, I know that a shot was with my (now gone) Spunik, but it looks a good as any of my TL120 slides.

I choose to shoot mostly in bright sunlight. I am always disappointed by the flatness of subdued colours. There are a few exceptions, like time exposures of neon lights and fairground rides, or B&W.

- Sputnik has a very good feature, regarding this dilemma, from my point of view :
the central lenses shutters (with perfect and simple synchro), resulting in very low vibration.
This combines with camera lightweight, which gives a better resistance to the movement of your body if you are not using a tripod.

I find that the TL120 is much better for hand held shots because of it's higher inertia. There is less shake and it is easier to trip the shutter. If you attach a cable release to the Sputnik, it will be improved, but you could do the same for the TL120.

The TL120 is also better for hand held shots because of the speed and convenience of it's built in metering. This is a big deal when I am traveling, as I always am. with my wife.

Here is another important superiority wrt TL120, apart from smaller focal length and smaller minimum aperture (practically f22+1/3 against f:22).

- by the way, I bought 220 rolls of Provia 400X, because I had the chance to get informed of Fuji's decision to stop production and I could buy the last stocks from some internet retailers.
For portrait photography, where even the fine grain of 400X is quite embarrassing,
I will use Provia 100F ... on a tripod (or a monopod ?).
And if one day I run out of Provia 400X, I'll switch to black and white 400 ISO ...

Since I shoot mostly in bright sunlight, I prefer to use 100ISO film. Mostly Provia 100F.

- last but not least :-( there is actually no more repair support for TL120.
3D world technicians disappeared, they no longer work for the company.
The last time I had my TL120 repaired by 3D World (shutter problem) was in june 2012.
In august 2013 it was absolutely impossible to get any service or technical data from 3D World,
despite their good will. And no independant technician in France or the US will be able to help, due to the lack of any spare parts and lack of technical information ...

Yes. Big problem.

I think we will see some franken-cameras appear as TL120s start becoming unrepairable. I hope mine will survive as long as film and processing is available. That may not be a tall order.

Timo

Subject: Re: Design fault in the 3d World system
Date: 2014-09-01 07:37:50
From: John Goodman

Jean-Paul wrote:

> so the main ennemy when taking pictures is camera shake

> This [central lenses shutters] combines with [the Sputnik]
> camera lightweight, which gives a better resistance to the
> movement of your body if you are not using a tripod.

I'm just a bystander in these interesting discussions, since
I'm not creating MF steroviews now, and I like what you
say, but I think the above runs counter to physical law. A
heavier camera, with its greater inertial mass, should
offer more resistance to movement than a lighter camera
would, when not mounted on a tripod. Although a heavy
camera might be more difficult to hold in position for a
long time, the actual movement of a light camera in
response to muscle tone and one's pulse would likely be
greater. And if this is moot because MF stereo cameras
are usually used with a a tripod, a heavier camera would
still inherently provide more damping against mechanical
vibration.

John Goodman

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-09-01 09:48:38
From: Don Lopp

On 8/31/2014 8:14 PM, jean-paul.nivoix@laposte.net [MF3D-group] wrote:

But second, if we agree to extend the question to
"how much inferior is Sputnik to TL120, with its simple optics"
as Coronet3D does brillantly ...
I have a few remarks to go even further :

- Sputnik lenses may distort a bit ... but yes, as it has to be used at f:16 or better f:22
or even further, there is a terrible vignetage flaw

Hello Jean-Paul,

   You did ask for our opinions! | I was not aware of any noticeable distortion in the many Sputnik images that I have seen in the last 15+ years. My principal MF viewer has lenses that do not have a significant pincushion or barrel distortion problem. Its fl is 68mm.

I am not aware that the Sputnik lenses show any signs of a vignetting flaw on 3D color film images.

>- there are other weaknesses in Sputnik optics, but in reality, the main dilemma in MF 3D photography does not lie in intrinsic optical quality, it is what >Coronet3D pointed out :
>you need the highest depth of field, in contradiction with the natural focal length of medium format / consequently you are using small lens aperture and low shutter >speed / so the main ennemy when taking pictures is camera shake, producing motion blur which will ruin all efforts to high quality images / one solution is high >speed films ... but they produce grain which will be visible due to stereoscope high magnification :-((

    I was not aware that many shooters of MF 3D images were not using a tripod on most shooting occasions!
    I consider the shutter release on the Sputnik to be a failure, as it is not a soft release, when compared to the shutter release found on both the Rolleidoscop and on the Heidoscop cameras. I have installed a softer shutter release on several Sputnik cameras.
    As regards to to Depth of Focus, the optical resolution available, plays a key roll in the amount of DoF available. High resolution limits the range of DoF available.   Lower resolution increases the amount of DoF range available.

At 40 lp/mm, Hyperfocal is at, /f'32 = 14'      7' to inf   Should be appropriate for the TL 120, IMO.
                                                    /f/22 = 20'            10' to inf
                                                    /f/16 = 27'             14' to inf
                                                     /f 11 =40'              20' to inf

At 30 lp/mm, Hyperfocal is at, /f32 = 12'            6' to inf
                                                   /f22 = 14'                7' to inf
                                                   /f16 = 20'               10' to inf

20 lp/mm, Hyperfocal           f/32 = 9.6'               4.8' to inf    Should be appropriate for the lower resolution Sputnik                                             f/22 = 14'           7' to inf
                                                 f/16 = 2o'          10' to inf
      >" Sputnik has a very good feature, regarding this dilemma, from my point of view :the central lenses shutters (with >perfect and simple synchro), resulting in very low vibration."This combines with camera lightweight, which gives a >better resistance to the movement of your body if you are not using a tripod."

    I don't agree, that the Sputnik shutter offers a very low vibration. Both the Heidoscop and the Rolleidoscop do offer a very low vibration, due to their air release shutter system. I have devised a very simple addition to the Sputnik shutter release, which I do believe does soften the Sputnik shutter release.
    I do not believe that, "combines with camera lightweight, which gives a better resistance to the movement of your body.... ." I believe that the opposite is the actual case. A heavier camera will offer more resistance to the movement of your body.

>"Here is another important superiority wrt TL120, apart from smaller focal length and smaller minimum aperture (practically f22+1/3 against f:22)."

    I do not consider the difference between f/22 and f/22+ to be of any significant consequence- it is only 1/3rd of an f/stop. I do not believe that many of us know the appropriate exposure within 1/3rd of an f/stop, in most occasions.

    Also, I am not aware that the difference between a focal length of 75mm and 80mm to be of any significant consequence either, as regards to DoF. I have been led to believe that most, MF 3D shooters focus at the Hyperfocal point, which in the case of the Sputnik, is best determined by trial and error, using B&W film. I consider the distance scale on the Sputnik to be an inaccurate disaster. Of the 20 plus Sputniks I have tested, none of the lenses when set at infinity were actually at infinity, as tested by using B&W film.

Cheers,

DON

- by the way, I bought 220 rolls of Provia 400X, because I had the chance to get informed of Fuji's decision to stop production and I could buy the last stocks from some internet retailers.
For portrait photography, where even the fine grain of 400X is quite embarrassing,
I will use Provia 100F ... on a tripod (or a monopod ?).
And if one day I run out of Provia 400X, I'll switch to black and white 400 ISO ...

- last but not least :-( there is actually no more repair support for TL120.
3D world technicians disappeared, they no longer work for the company.
The last time I had my TL120 repaired by 3D World (shutter problem) was in june 2012.
In august 2013 it was absolutely impossible to get any service or technical data from 3D World,
despite their good will. And no independant technician in France or the US will be able to help, due to the lack of any spare parts and lack of technical information ...

Subject: Re: Fwd: Re: [MF3D-group] Design fault in the 3d World system
Date: 2014-09-01 11:50:07
From: coronet3d

Hi Don,

"I was not aware that many shooters of MF 3D images were not using a tripod on most shooting occasions!"

I probably only shoot with a tripod half of the time with my Sputnik. When you're shooting portraits, particularly of children, it's real hard to lug a tripod around. Compared to most cameras of the era, I agree that the shutter release on the Sputinik is fairly light and smooth. A Compur might have a lighter action but the Sputnik is superior to Rapax shutters IMO and pretty much all of the 35mm stereo cameras manufactured in the 1950s outside of the Stereo Vivid.

Steve

Subject: Re: Design fault in the 3d World system
Date: 2014-09-01 11:58:47
From: coronet3d

I think the ergonomics of the camera are more important than the weight. Having the shutter release in the front like the Stereo Vivid and numerous TLRs is better than the position of the shutter release on the Sputnik, Rapax shutters, Compur shutters and numerous Kodak shutters. However, the shutter release of the Sputnik is well placed and IMO relatively light compared to other shutters of the period. Kodak shutters of the period, like the one fitted to their Reflex II camera are much heavier than the Sputniks.

Steve