Stereo/3D Projections

[holmburgers]

Howdy all,

So lately I've been stricken by the desire to see my pictures in 3D. So far I'm still in the planning stages, but I do have a lot of the necessary equipement.

I've got 2 Kodak Carousels, 2 Canon AE-1's with matching 50mm lenses, a Da-Lite Silver-Lite Lenticular screen (thanks dad for buying the coolest stuff & then leaving it boxed, in the basement, for years!). Unfortunately I don't have 2 'like' lenses for the projectors yet (I have a 2.5", a 4.5" & a 102mm, would love to do some trading...) or a suitable camera bar.

Anyways, I'm just curious if anyone has done this and could give me some pointers or share their ideas. It seems like a really cool thing, and I think if I can pull it off I could actually entertain my friends w/ slide shows. Maybe 3D could've spared slide shows from garnering a reputation as "boring as hell". Of course, I don't think they're boring....

This website is fantastic, has lots of valuable information - Dead Link Removed

Cheers!

 

[reellis67]

Aligning two projectors is not easy, but it can be done. I would suggest that you ask around on the Yahoo! group photo-3d as there are a great number of people who project various stereoscopic formats all the time there and they may be able to provide some insight into the process that I cannot. My experience has been with stereo projectors projecting mounted stereo transparencies, so the alignment is not a problem. You'll need to get two polarizing filters that fit your lenses, once you get a pair of the same lens, then rotate one perpendicular to the other. This will allow the right and left sides of the pair to be seen by the correct eye. Then you'll want to get a decent pair of glasses for viewing. Most of my experience with this has been with these two people: Steve Berezin and Dead Link Removed. Both are very skilled in all aspects of stereo photography and both are very professional and always happy to help others.

Stereo photography is very rewarding, at least in my experience, but projecting can be a real bear unless you have a good idea of what you are doing. Hand viewing stereo pairs made with a stereo Realist is my personal favorite way to view stereo images, but that's just me. I'm hopelessly addicted to View-Master reels so I'm a little biased in that regard. I'd be interested to hear how this project goes!

- Randy

 

[holmburgers]

Thanks for the reply. Yeah I'm sure it won't be easy to do the aligning. But I'm picking up a slide cutter and mounts today, so I can carefully register them, and I'll to figure out a good system for stacking the projectors. I'm also compiling a list of cool shots.

It'll be a long, drawn out process I'm sure, but as you said, hopefully very rewarding. I can't get over the brilliance of most slide projections & I can only imagine that with 3D it'll seem as though I could walk through the picture.

But I digress, I'll try to report back once I've done it, and thanks for the links.

 

[reellis67]

I can't get over the brilliance of most slide projections & I can only imagine that with 3D it'll seem as though I could walk through the picture.

But I digress, I'll try to report back once I've done it, and thanks for the links.

Yep, that's the magic It's really amazing when done right. Let us know how it goes...

- Randy

 

[Chan Tran]

I wonder how do you project 3D images? You must have a way so that the left eye only sees the left image and the right eye only sees the right image.

 

[reellis67]

Chan,

Polarizing filters are used. They are set perpendicular to each other, and glasses with matching polarizes are used to view the projected image. This allows only the right eye to see the right eye image, and the left eye to see only the left eye image. You can also project anaglyphs using two colors, usually red and blue, but this is not a comfortable to view in my opinion. The only other way that I am aware of is shutter glasses, which blank out one eye, then the other, very fast and in sych with a special projecting unit so that when the right eye can see, the right eye image is projected (and the left eye is blocked by the glasses), and the same happens for the left eye (left image projected/right eye blocked).

- Randy

- Randy

 

[TracyStorer]

The glass bead screen is also important for reflecting the polarized projected light back to your (polarized glasses wearing) eyes.

I wonder how do you project 3D images? You must have a way so that the left eye only sees the left image and the right eye only sees the right image.

 

[Chan Tran]

thanks Tracey, because a diffused screen would negate the effect of the polarized light.

 

[John Koehrer]

The glass bead screen is also important for reflecting the polarized projected light back to your (polarized glasses wearing) eyes.

Is it correct to say the lenticular screen will not work?

 

[reellis67]

John,

There is some good info on projection screen choice on this page. I believe that lenticular screens are fine for slide projection. (just don't use them for digital projectors - they cause moire patterns).

Dead Link Removed

- Randy

 

[Photo Engineer]

One of my friends has a prism lens that goes on his Nikon cameras and creates 2 frames on one frame of 35mm or 2 frames on one digital sensor capture. He scans his negative, which is a stereo pair and has software that produces a polarized image on his HDTV. Wearing standard polarizing glasses, he sees the stereo picture in vivid detail. He also has software to make digital prints from his film stereo pairs which he can put into an old stereo viewer to give beautiful color photos in a format popular about 100 years ago.

PE

 

[reellis67]

PE,

I have one of those too - for my film EOS camera. They do a nice job, but mine at least has a closer inter-ocular separation than my Realist camera, so it doesn't work well for close-ups. Loreo makes a macro stereo lens attachment that looks really interesting, but I'm a little skint right now, so no macro stereo for me

I can, and regularly do, make Holmes format stereographs from the prints, and they look really neat. It's a snap to do, even by hand, but cutting the neat looking curve at the top that Keystone used is a bit tricky. There's something really rewarding about sitting down to look at your own stereographs...

- Randy

 

[Photo Engineer]

PE,

I have one of those too - for my film EOS camera. They do a nice job, but mine at least has a closer inter-ocular separation than my Realist camera, so it doesn't work well for close-ups. Loreo makes a macro stereo lens attachment that looks really interesting, but I'm a little skint right now, so no macro stereo for me

I can, and regularly do, make Holmes format stereographs from the prints, and they look really neat. It's a snap to do, even by hand, but cutting the neat looking curve at the top that Keystone used is a bit tricky. There's something really rewarding about sitting down to look at your own stereographs...

- Randy

Randy;

There is a double exposure method that was in the Kodak Stereo handbook which shows how to take closeups in stereo by moving the camera to simulate the correct intra-ocular distance. My friend has a jig on his tripod for that, as well as for extremely large intra-ocular distance for special shots.

PE

 

[reellis67]

Yep, I've got a slide-bar, made by Manfroto for macro work, that I mounted sideways on the tripod head. I pasted a small scale on there marked with focus distances so I can slide it the 'optimal' inter-ocular distance for a subject that far away. It works well so long as there is no wind It works well for far away subjects too, if you have a longer slide bar.

- Randy

 

[Neanderman]

Aligning two projectors is not easy, but it can be done.

Nonsense. For 13 years my job entailed aligning anywhere from 2 to 32 projectors. And, yes, we did some 3-D shows. The real problem is not projector alignment, but slide registration. We used pin-registered cameras and slide mounts, but neither of those are absolutely required.

The easiest way to align two projectors is to set one above the other. Just build yourself a shelf that straddles one projector and set the second one on it.

Ed

 

[Neanderman]

Is it correct to say the lenticular screen will not work?

No. A lenticular screen is exactly what you want.

Ed

 

[reellis67]

Nonsense. For 13 years my job entailed aligning anywhere from 2 to 32 projectors. And, yes, we did some 3-D shows. The real problem is not projector alignment, but slide registration. We used pin-registered cameras and slide mounts, but neither of those are absolutely required.

The easiest way to align two projectors is to set one above the other. Just build yourself a shelf that straddles one projector and set the second one on it.

Ed

I appreciate your point of view, but mis-registered images cause eye strain in most viewers. Stereoscopic projection may be a snap for someone with 13 years of experience, but for a beginner it can be a bit more challenging. Stacking projectors is the standard method for non-stereo projection units though, and as long as you understand what you are doing it can be done easily enough, but I would not want to view a long series of images on projectors setup by someone who had never done it before.

The original poster stated that he was trying this for the first time using images made with a non-stereo camera, which means that there is going to be rather a lot of work needed to get each slide displayed properly to minimize eye strain, and the setup is likely to need adjusting for each pair. Certainly it can be done, and I think that the OP should give it a shot, but I'm not convinced that my point of view is nonsense...

- Randy