3D Lens attachment (w Mirrors)

Started Jun 29, 2015 | Discussions
Barretlight Regular Member • Posts: 302
3D Lens attachment (w Mirrors)
1

There have been a few lens for SLR cameras like Loreo 3D Lens or Holga 3d lens.
Lately a few  lens attachments also appeared (like poppy 3d only for iphones and Kula deeper).
Is any of those actually worth it in quality? I know that they cut the resolution in half to produce an SBS image.
Also are there any designs for a small dIY beamsplitter for a phone or compact camera.
I will attempt to make one my self but its not easy to cut mirrors, even plastic mirrors.

Sailor Blue
Sailor Blue Forum Pro • Posts: 15,527
Re: 3D Lens attachment (w Mirrors)

Barretlight wrote:

There have been a few lens for SLR cameras like Loreo 3D Lens or Holga 3d lens.
Lately a few lens attachments also appeared (like poppy 3d only for iphones and Kula deeper).
Is any of those actually worth it in quality? I know that they cut the resolution in half to produce an SBS image.
Also are there any designs for a small dIY beamsplitter for a phone or compact camera.
I will attempt to make one my self but its not easy to cut mirrors, even plastic mirrors.

I tried a couple of mirror attachments, including the Pentax Stereo Adapter, on a Konica Minolta A200 camera and the results were unsatisfactory.  I then tried using a slider with my Canon 7D and got excellent 3D images of still subjects, but just doing the cha cha worked almost as well and was a lot easier.  The slider just didn't work for any subject that could move - it took too long between exposures.

Finally I bought a Fuji Real 3D W3 and forgot about all the kludge ways to take 3D photos except for the times when I am doing landscape or architecture photography.

-- hide signature --

Living and loving it in Pattaya, Thailand. Canon 7D - See the gear list for the rest.

 Sailor Blue's gear list:Sailor Blue's gear list
Fujifilm FinePix Real 3D W3 Canon EOS 7D Canon EOS 5DS R Tamron SP AF 90mm F/2.8 Di Macro Tokina AT-X 16-28mm f/2.8 Pro FX +9 more
OP Barretlight Regular Member • Posts: 302
Re: 3D Lens attachment (w Mirrors)

Thanks for your answer.
I ve been thinking about fuji W3. Trying to find a good deal to buy a second hand one.
They are very rare.
Too bad there are no new 3d cameras. I hope the re-introduction of VR tech will change that.

Oleg L K Regular Member • Posts: 257
Re: 3D Lens attachment (w Mirrors)

The 3d attachments - beamsplitters - are made for 50mm lenses on full-frame 35mm cameras. They aren't compatible with compact/bridge cameras like A2 or A200. Maybe they work with 35mm lenses on APS-C, I didn't try it.
Then, you need to find the right lens for the specific attachment. And leveling the attachment vs the lens is important too.

I would recommend Loreo lens over a beamsplitter. Less weight/size, less hassle, better quality.

Another consideration: working aperture: f/11-f/22 for the Loreo, f/4 (optimal) for SKF1 beamsplitter. The latter eats some 1.5-2 stops of light too.
So beamsplitters permit twice as smaller exposure, could be crucial for moving objects. But the Loreo gives more DOF.

But I need to stress the importance of not exceeding the 6.5cm interocular distance. Otherwise you are drawn into hyper-stereo land. It may look like impressive 3d effect while you evaluate the instrument, but then your real-world pictures become toy-like - unrealistic.
Unfortunately the current model of Loreo has enlarged stereo-base. I'd recommend getting the discontinued old model.

OP Barretlight Regular Member • Posts: 302
Re: 3D Lens attachment (w Mirrors)

Thanks for your response.
To say the truth I have abandoned the DIY beamsplitter idea. It will be a lot of trouble cutting and then aligning the mirrors, it will reduce the resolution to more than half (as the middle portion will be blurred) and most importantly for cameras larger than cellphones it will be quite big.

I have now turned towards either

1. buying a Fuji W3 wich is very compact has a 3d screen but it has a narrow 35mm lens and is not of great IQ.

or 2. building a compact 3d rig. That rig could be two android smartphones (like Samsung GS III) or two canon cameras with SDM firmware (like S95). In the case of the phones it would be a compact maybe foldable design controlled by a bluetooth application so both cameras could be fired at the same time. I have to check the app on two random phones to see how good the synchronization is. I dont expect miracles. But for steady subjects it will surely work better than the cha-cha method. Also with this option I could have a true to human eyes stereo base of 6.5-7 cm

Now with the 2x canon s95 rig: It will have much better image quality (Especially in low light) but the stereo base will be close to 8cm if I am calculating correctly.
I know what you re saying about the interocullar distance. It baffles me also. Some people say that a bit more than 7 cm gives you a better 3d effect. Fuji for example has an SB of 7,5cm.
It will certainly look Great on a 3dtV. Now if in the near future those images are viewed on a head mounted display like occulus or the google cardboard (available now) will they look unnatural? Thats the real question!!!

crunchy_3d Regular Member • Posts: 140
Re: 3D Lens attachment (w Mirrors)

Barretlight wrote:

I know what you re saying about the interocullar distance. It baffles me also. Some people say that a bit more than 7 cm gives you a better 3d effect. Fuji for example has an SB of 7,5cm.

The difference between 7 and 8cm is not large. When showing several pictures taken with 7cm or 8cm you would never find out what stereo base was used for particular picture. The stereo base is about 77mm for a pair of S95, according to my measurements if one camera is upside down. The stereo effect also largely depends on projected picture size and the viewing angle (according to "taken" angle).

Damir

Cullings Regular Member • Posts: 200
Re: 3D Lens attachment (w Mirrors)

Oleg L K wrote:

. . . .But I need to stress the importance of not exceeding the 6.5cm interocular distance. Otherwise you are drawn into hyper-stereo land. It may look like impressive 3d effect while you evaluate the instrument, but then your real-world pictures become toy-like - unrealistic. . . .

Sometime you want to increase the interocular distance. Look at the stereo base extenders at www.cyclopital3d.com. Here's what they say about their Fuji-W3 extender:

"The Cyclopital3D Stereo Base Extender uses perfectly aligned, high quality front surface mirrors to effectively increase the stereo base of your Fuji W3 to 225mm. This lengthening of the stereo base allows you to get 3X further away from your subject while still maintaining an acceptable level of parallax....The Stereo Base Extender is perfect for wildlife subjects, weddings, sporting events, distant portraits and band performances."     (see sample photos)

It really works to improve the stereo effect in more distant subjects.  They have base-extenders for JVC, Panasonic, and Sony cameras/camcorders too.  I have the JVC extender.  it works great, but is large and somewhat fragile. No "lens cover" is supplied. I made two lens covers for mine. Price is about $500.

Cyclopital3d stereo base extender for Fuji-W3

-John S.

 Cullings's gear list:Cullings's gear list
Canon EOS 7D Canon EOS M Sony a7 Sony a6000 Sony E 10-18mm F4 OSS +5 more
Sailor Blue
Sailor Blue Forum Pro • Posts: 15,527
Re: 3D Lens attachment (w Mirrors)

Oleg L K wrote:

The 3d attachments - beamsplitters - are made for 50mm lenses on full-frame 35mm cameras. They aren't compatible with compact/bridge cameras like A2 or A200. Maybe they work with 35mm lenses on APS-C, I didn't try it.

They work just fine with any camera with any sensor size as long as you set the equivalent focal length to something near 50mm.  They will actually work with other focal lengths too, just not as well since the interocular spacing isn't correct.

Then, you need to find the right lens for the specific attachment. And leveling the attachment vs the lens is important too.

I would recommend Loreo lens over a beamsplitter. Less weight/size, less hassle, better quality.

Another consideration: working aperture: f/11-f/22 for the Loreo, f/4 (optimal) for SKF1 beamsplitter. The latter eats some 1.5-2 stops of light too.
So beamsplitters permit twice as smaller exposure, could be crucial for moving objects. But the Loreo gives more DOF.

But I need to stress the importance of not exceeding the 6.5cm interocular distance. Otherwise you are drawn into hyper-stereo land. It may look like impressive 3d effect while you evaluate the instrument, but then your real-world pictures become toy-like - unrealistic.
Unfortunately the current model of Loreo has enlarged stereo-base. I'd recommend getting the discontinued old model.

Hyper-stereo is fine for landscapes or architectural photography where the subjects are a long distance from the camera.  If you don't use a wider than 6.5cm interocular distance the images come out looking non-3D.  The rule of thumb for interocular distance is:

Stereo Base = distance of nearest object/30

We are used to really distant objects looking flat since they are beyond the distance where we see 3D so you don't want to use too large a stereo base.

-- hide signature --

Living and loving it in Pattaya, Thailand. Canon 7D - See the gear list for the rest.

 Sailor Blue's gear list:Sailor Blue's gear list
Fujifilm FinePix Real 3D W3 Canon EOS 7D Canon EOS 5DS R Tamron SP AF 90mm F/2.8 Di Macro Tokina AT-X 16-28mm f/2.8 Pro FX +9 more
Oleg L K Regular Member • Posts: 257
Re: 3D Lens attachment (w Mirrors)

I'm answering several questions in one post.
1) dual-camera rig and interocular distance:
- if you want the best possible solution, make stereo-base adjustable with the minimum being below 6.5cm
- If you cannot make variable stereo-base, keep it no larger than 6.5cm
- the new Olympus Air camera is 5.7cm in diameter; isn't it the first candidate?

2) I tried beamsplitter on HP850 and Minolta A2. Incompatible, point.

Sailor Blue
Sailor Blue Forum Pro • Posts: 15,527
Re: 3D Lens attachment (w Mirrors)

Here is the test self portrait that I made with my Konica Minolta A200 using the Pentax Stereo Adapter. I shot it at 1/160sec, f/3.2, and at 16.3mm (equivalent to 63 mm on a full frame sensor camera) and I used the built-in flash.

I know how bad the portrait is but the whole reason for shooting it was to test the Pentax Stereo Adapter. As you can see, the stereo adapter worked fine.

Some of the edge darkening is due to the effective focal length being longer than 50mm, some was due to some deterioration of the silver coating along the edges of the mirrors.

-- hide signature --

Living and loving it in Pattaya, Thailand. Canon 7D - See the gear list for the rest.

 Sailor Blue's gear list:Sailor Blue's gear list
Fujifilm FinePix Real 3D W3 Canon EOS 7D Canon EOS 5DS R Tamron SP AF 90mm F/2.8 Di Macro Tokina AT-X 16-28mm f/2.8 Pro FX +9 more
OP Barretlight Regular Member • Posts: 302
Re: 3D Lens attachment (w Mirrors)

Oleg L K wrote:

I'm answering several questions in one post.
1) dual-camera rig and interocular distance:
- if you want the best possible solution, make stereo-base adjustable with the minimum being below 6.5cm
- If you cannot make variable stereo-base, keep it no larger than 6.5cm
- the new Olympus Air camera is 5.7cm in diameter; isn't it the first candidate?

Olympus air sounds like a great idea. However I dont think that can be synchronized. Did olympus state anything about controlling two cameras at the same time.
Actually there are other connected cameras like the Sony QX100 (1" sensor like the RX100) that are very small in size but from what i ve read two of them cannot be controlled by one phone by wifi, just one at a time. Sony has not realized the potential to have them linked like the gopros. Would create the best compact 3d camera system.

The 6.5 cm could be achived by using some older canon cameras and SDM. But I think the best image quality could come from a pair of canon s95's ...but the closest SB they get is only 7.7cm. I am leaning toward this system... I hope its not too exagerated compared to the 6.5 cm normal eye distance.

2) I tried beamsplitter on HP850 and Minolta A2. Incompatible, point.

OP Barretlight Regular Member • Posts: 302
Re: 3D Lens attachment (w Mirrors)

Not bad. The 3d effect works quite well.

But the portrait mode is very limiting if you are going to view the pictures on a wide 16:9 3dtv.

Cullings Regular Member • Posts: 200
Re: 3D Lens attachment (w Mirrors) * Back-to-Basics *
1

Interocular (io) distance vs Interaxial (ia) distance:

The separation between our human eyes is called the Interocular distance.
As a rule of thumb this distance is 65mm.

Interaxial (ia) distance is the separation of the stereo camera pair.
ia should vary shot to shot and changes our impression of scale.

The Depth Budget:
Each shot has a maximum amount of usable depth within which to create effective 3D.

Maximum Deviation:
The maximum deviation on screen is a measurement of Parallax.
It limits what is safe for the viewer. Avoids eye strain, and in turn headaches
and sickness. Too much deviation must be avoided, especially positive Parallax which could (depending upon screen size and seating position) cause our eyes to diverge. It is possible to ‘break the rules’. But not, continuously or, by large amounts for long periods.

Guides for TV (as defined by Sky):
Positive Parallax (appears behind the viewing plane): +2%
Negative Parallax (appears in front of the viewing plane): ­-1%
Total Parallax: 3%

The illusion of stereoscopic vision:
It’s important to note that the illusion of S3D created on the screen is
not the same as our perception of depth in real life. Our eyes have a fixed
FOV. Cameras do not. We have brains designed to fill in the gaps.
Cameras do not.

Interaxial (ia) and Convergence (cv) distances should vary shot to shot.

There is no ‘real life’ value to dictate Interaxial distance. Especially when close ups may place someones head 10 foot high on the cinema
screen. Fixing Interaxial distance is hugely restrictive, and ia should
in fact vary shot to shot.

Setting ia and cv is a creative decision to support the story. Together they define the scale of the viewer and the scene. We can view the shot as gods or insects - it’s up to the Director of Photography and the Director to decide.

1/30th rule of thumb:
Interaxial distance will generally be around 1/30th of the distance
to the convergence point. So if you're converging 30m away then the
camera pair should be 1m apart.  (!!!)

When shooting native S3D we’d ideally need two camera rigs:

A mirror rig. For action close to the camera.
( where ia is less the width of the camera )
A side by side rig. For action far from the camera

downloaded 8 July 2015, from:
www.designimage.co.uk/tips-for-creating-stereoscopic-3d/

-- hide signature --

my note: this is from the viewpoint of a cinematographer.   Varying interaxial distance can be very difficult.   I think the "cha-cha" method may be the easiest.  Or perhaps "cha-cha-cha-cha".     - John S

 Cullings's gear list:Cullings's gear list
Canon EOS 7D Canon EOS M Sony a7 Sony a6000 Sony E 10-18mm F4 OSS +5 more
Gerry Siegel
Gerry Siegel Veteran Member • Posts: 3,076
Re: 3D Lens attachment (w Mirrors)

Barretlight wrote:

Oleg L K wrote:

I'm answering several questions in one post.
1) dual-camera rig and interocular distance:
- if you want the best possible solution, make stereo-base adjustable with the minimum being below 6.5cm
- If you cannot make variable stereo-base, keep it no larger than 6.5cm
- the new Olympus Air camera is 5.7cm in diameter; isn't it the first candidate?

Olympus air sounds like a great idea. However I dont think that can be synchronized. Did olympus state anything about controlling two cameras at the same time.
Actually there are other connected cameras like the Sony QX100 (1" sensor like the RX100) that are very small in size but from what i ve read two of them cannot be controlled by one phone by wifi, just one at a time. Sony has not realized the potential to have them linked like the gopros. Would create the best compact 3d camera system.

The 6.5 cm could be achived by using some older canon cameras and SDM. But I think the best image quality could come from a pair of canon s95's ...but the closest SB they get is only 7.7cm. I am leaning toward this system... I hope its not too exagerated compared to the 6.5 cm normal eye distance.

2) I tried beamsplitter on HP850 and Minolta A2. Incompatible, point.

if i were doing some home brew expermenting, and had a mecahanical bent, I would like to play with a couple of the Olympus Air new models. They have the advantage of 1) a tripod bush 2) a reasonable interocular close distance by size, and a decent size sensors 3) a choice of modeslty priced sharp lenses. 4) ability to mount without reversing the units upside down for one and also sttretching out the base on a rail to get a wider base of the lenses. A 30 mm lens would do fine and they woud produce sharp images...I would not mess with matching zooms...the 16 meg output would be superb...I like the 4: 3 for stereo close to the old slides and versatile with in this case the wide size long vs the beamsplitter effects.  Dual processing true...but why not?  I would construct a single cyclopean viewer for compactness if I did not want to carry a phone. As to synchrnization,,,that will take some fooling around. I rather think it can be achieved though. How about you?

 Gerry Siegel's gear list:Gerry Siegel's gear list
Panasonic ZS100 Panasonic Lumix DMC-GX7 Olympus E-M1 Panasonic Lumix DMC-GX8 Panasonic Lumix DC-G9 +4 more
Oleg L K Regular Member • Posts: 257
Re: 3D Lens attachment (w Mirrors)

Here is the test self portrait that I made with my Konica Minolta A200 using the Pentax Stereo Adapter. I shot it at 1/160sec, f/3.2, and at 16.3mm (equivalent to 63 mm on a full frame sensor camera) and I used the built-in flash.

I know how bad the portrait is but the whole reason for shooting it was to test the Pentax Stereo Adapter. As you can see, the stereo adapter worked fine.

Some of the edge darkening is due to the effective focal length being longer than 50mm, some was due to some deterioration of the silver coating along the edges of the mirrors.

With my SKF-1 adapter I had to crop the center section on small-sensor cameras. Thus different beamsplitters have different compatibility.

chrvi New Member • Posts: 1
Re: 3D Lens attachment (w Mirrors)

Hello guys,

I'm glad I found this thread. I'm also considering buying a pair of Canon S95 cameras and connect them in a rig but I worry the minimal distance between their lenses will be too great for a natural look of the 3d photos (I wanted to shoot portraits most and dislike hyper-stereo 3D photos) - which I also found discussed in this thread.

If I understand correctly, I simply cannot achieve the "real" looking 3d images 'cause the lenses will always be to far from each other (given they're both in the landscape orientation)

So just one dumb question - has use of zoom any effect on the resulting 3d image?
I mean, if I zoom in/out will there be any difference in the resulting 3d effect?
Or will the only effect be a smaller area being captured by both cameras?

Thanks,

Radek

PS: ...and it's sad one cannot use external flash with S95... and cannot play with shallow DOF as with DSLRs... one always needs to search for compromises...

PPS: Sorry, this reply should have been in another place in the thread tree but I'm not able to withdraw this post and create in a proper place any more...

crunchy_3d Regular Member • Posts: 140
Re: 3D Lens attachment (w Mirrors)

chrvi wrote:

I'm glad I found this thread. I'm also considering buying a pair of Canon S95 cameras and connect them in a rig but I worry the minimal distance between their lenses will be too great for a natural look of the 3d photos (I wanted to shoot portraits most and dislike hyper-stereo 3D photos) - which I also found discussed in this thread.

Yes, for portraits, 77mm may be slightly exaggerated. Even if you have almost no background on the picture, you might result in exaggerated depth in z-axis (although stereo parallax would be still within limits if there is no background).

If I understand correctly, I simply cannot achieve the "real" looking 3d images 'cause the lenses will always be to far from each other (given they're both in the landscape orientation)

Yes, slightly exaggerated "depth".

So just one dumb question - has use of zoom any effect on the resulting 3d image?
I mean, if I zoom in/out will there be any difference in the resulting 3d effect?
Or will the only effect be a smaller area being captured by both cameras?

Yes, 2x zoom will result in 2x larger stereo parallax (you should not exceed 1/30 of the landscape picture width). If there is no background (you take only head with one-colour background), you may still get less than 1/30 stereo parallax even with 70-80mm equivalent. However, the resulting stereo picture might be still slightly exaggerated in z-axis (depth). So nose might appear slightly longer than in reality. On the other hand, zooming decreases the "feel of depth", so you may result in useful picture. Everything depends on the viewing device as well, of course.

Why don't you try by yourself and take two (horizontally displaced) pictures of some let's say larger teddy-bear?

PS: ...and it's sad one cannot use external flash with S95... and cannot play with shallow DOF as with DSLRs... one always needs to search for compromises...

At least you can trigger external flash by internal one? You may decrease flash power in StereoData Maker (I think it's possible). Some time ago I used my electronics which directly triggered external flash, but it does not work on the newest (high-precision) SDM versions.

Damir

Brian F Flint
Brian F Flint Forum Member • Posts: 86
Re: 3D Lens attachment (w Mirrors)
1

Here is a rig which uses two cameras and a mirror. The stereo base ( distance between the lens ) can be adjusted down to 30mm

https://www.flickr.com/photos/26973646@N05/15664046779/in/album-72157644982222370/

 Brian F Flint's gear list:Brian F Flint's gear list
Nikon 1 V1 Canon MP-E 65mm f/2.5 1-5x Macro Nikon 1 Nikkor VR 10-30mm f/3.5-5.6 Nikon 1 Nikkor VR 30-110mm f/3.8-5.6 +1 more
crunchy_3d Regular Member • Posts: 140
Re: 3D Lens attachment (w Mirrors)

What zoom have you used on Nikons (35mm equivalent) for 40mm stereo base?

You wrote that for 35 degrees of view you have to set 50mm stereo base. 35 horizontal degrees of view corresponds to about 60mm lens (35mm equivalent).

I suppose that stereo base would be higher for larger cameras (with larger lenses). Once I tried similar solution with my m43 Panasonics and the measured stereo base was relatively large (if I remember correctly, in vicinity of 10cm), but now I cannot remember the lens focal length. You encouraged me to try again.

The readers should be aware that for non-SDM cameras we might face synch problems. The swans picture on flickr page have a hint of missynch (some feathers on left swan, also slightly on the water). However, for portrait photography (without wind) it could be still very good solution.

Brian F Flint
Brian F Flint Forum Member • Posts: 86
Re: 3D Lens attachment (w Mirrors)

crunchy_3d wrote:

What zoom have you used on Nikons (35mm equivalent) for 40mm stereo base?

You wrote that for 35 degrees of view you have to set 50mm stereo base. 35 horizontal degrees of view corresponds to about 60mm lens (35mm equivalent).

I suppose that stereo base would be higher for larger cameras (with larger lenses). Once I tried similar solution with my m43 Panasonics and the measured stereo base was relatively large (if I remember correctly, in vicinity of 10cm), but now I cannot remember the lens focal length. You encouraged me to try again.

The readers should be aware that for non-SDM cameras we might face synch problems. The swans picture on flickr page have a hint of missynch (some feathers on left swan, also slightly on the water). However, for portrait photography (without wind) it could be still very good solution.

I have two different zoom lenses for each of the Nikon 1 V1 cameras . They are 10-30mm ( 27 - 81mm , 35mm equivalent ) and 30-110mm ( 81 - 297mm , 35mm equivalent ). Depending on what I am photographing I may use either of the lenses. Using the 30 to 1 ratio rule for good stereo effect, if the stereo base is say 40mm then the distance from subject to sensor needs to be around 30 x 40mm = 1200mm. I would say for this distance the focal length of the lens need to be about 60mm ( 35mm equivalent ) or longer, when used on the rig with a mirror.

For best sync , I think in the case of the swans photo , I pressed the shutter button on each camera by hand ( or I may have used the infra-red hand unit, directed at both cameras ). It is important the have the exposure and focusing in manual mode, so that both cameras take the photo instantly.

 Brian F Flint's gear list:Brian F Flint's gear list
Nikon 1 V1 Canon MP-E 65mm f/2.5 1-5x Macro Nikon 1 Nikkor VR 10-30mm f/3.5-5.6 Nikon 1 Nikkor VR 30-110mm f/3.8-5.6 +1 more
Keyboard shortcuts:
FForum MMy threads