Mike Chaney's Tech Corner

Ok gang.  I'm curious how many people can see 3D on the practice image at the bottom of the page below after reading the instructions.  The photo is displayed in the cross-view mode which means you basically need to cross your eyes a little to see it.  Just follow the instructions on the page and then see if you can get the 3D effect on the practice image at the end of the article.  One thing that the online instructions often don't tell you is that you should be positioned directly in front of the pictures (nose about lined up with the center) and that your head angle is important so tilting your head to the left/right slightly often helps to align the photos.  I'm interested in how many people can actually achieve the cross-view 3D viewing.  So far, I've found that less than 20% of people are able to see the depth effect.

http://www.starosta.com/3dshowcase/ihelp.html

While it seems to be the most difficult method to teach (and I'm not sure everyone can even BE taught), I find the cross-view method far better than any other method for viewing 3D photos because you can print much larger photos (8x10 or larger) and freeview them on a regular sheet of photo paper with no viewer or tools.  3D (stereo) viewers are available for much smaller prints but once you get used to the crossview method, nothing beats it.  Only downside is some eye strain but once you get used to it, it is minimal and the eyestrain goes away almost completely.  That said, please don't strain yourself.  :)  The other method for freeviewing is parallel (sometimes called relaxed) view.  That's similar to how you used to view those stereogram books that were popular in the early 90's where you relax your eyes and focus at a distance.  The problem with that is the fact that you must display the side-by-side images no larger than about the size of a business card (total width) to easily be able to get the effect and anything larger than about 4 inches across is physically impossible for that method.

Thanks for any feedback,
Mike

Hi Mike, got it almost strait away ;D I used to love the stereo gram books of the 90's. This is the first time I have seen this type of 3d it looks great.
Phill

Yes I can see the 3D, but infact I see three images - one in the center in 3D and two on either side sort of blured.

I will give eyes a rest and try again tomorrow.

Reminds me of my miss spent youth, when we used to have Dinah Dors pics and red and green viewers, prob. that's why my eyes are not so good now. :) :)

Jeff

That's normal.  If you put both hands up on the side and move them in slowly, you can actually block out the two superfluous copies on the sides and only see the 3D copy.

Mike

fwiw, you can take 3d images with a normal camera of static subjects. The easy way is tripod mounted, and move the tripod sideways for the second image. It depends on the subject but probably about an eight inch separation would be a good starting point. You can view the parallel images at large scale, by putting a sheet of card perpendicular to the screen/print to your nose. Your left eye then can only see the left image, your right the right image.

I used to make anaglyphs a few years back. I got sort of interested in enhancing the 3d effect by moving the camera distances further, and printing at different overlaps. I bought a couple of cheap p&s's, and made a bracket to take both, at adjustable positions, wired a push button switch into both cameras to fire them at the same time. It worked fine, but in the end the novelty wore off  ;). For anaglyphs you can either use colour filters over the lens, or apply the filter afterwards in post. A lens filter is probably simplest, since you can use the same filter in your viewing glasses. Making anaglyph prints would be fun, you'd need some transparency/image blending setting, else you would see the top print only, with a fringe of the bottom print.

I suppose these days you'd refresh the screen with the two images in synch with some lcd glasses. Apparently there are different methods shown on U-tube, for example.

Best wishes,

Ray

You cannot freeview any parallel image at a scale larger than about 5 inches across (2.5 inches wide for each left/right image) because regardless of how far you sit from the print, your eyes would have to diverge in order to see the 3D effect.  Lots of people can cross their eyes but I've yet to find anyone who can diverge them.  Putting a card perpendicular to the screen at your nose doesn't make sense either because the card would have to extend almost all the way from your nose to the screen to block out the other side.  But that point is moot anyway because you're not going to get your eyes to diverge... so if you print, for example, an 8x10 of a parallel view 3D image, you're not going to be able to view it without splitting up the print (overlapping it so that the 3D part is no more than 4 to 5 inches apart) and/or using mirrors.

Print an 8x10 cross-view print, however, and for someone used to cross viewing, it'll be easy.

Mike

Hi Mike,

It did. Also, bear in mind, when I was doing this, there were not many large vdu's, nor anything above a4 printer that was at any sort of affordable price. Anaglyphs with the simple coloured glasses were the solution if size mattered. The point and shoots I used had huge 1Mp sensors  :D  (Agfa's, iirc)  but 30 years prior to that I'd used 35mm slides and a home made viewer, and I had known a guy who gave me some sepia toned stereo glass slides he had made when a youngster, probably back in Victorian times.

Technology evolves slightly faster than the human eyeball, I guess. Making a viewer for parallel images is not difficult, a couple of mirrors and a cardboard box will do it simply enough, but maybe three images are better than one. ;)

Best wishes,

Ray

I have been able to free view in both parallel and cross-view modes for many years and have collected stereo views and made my own , both cards and slides. With practice most people can achieve cross-view viewing and a lesser number - parallel viewing. I've always enjoyed viewing in stereo and am pleased that the interest in this form has increased recently.

Not me.  Maybe it's my astigmatism and glasses.  Have never been able to do this unless I go extremely crosseyed, then I get about a half second glimpse that almost works followed by a three and a half minute headache. Those 3D weird pictures that they sell in card shops and novelty stores (on calendars mostly I think)  - where you have to get to within a few inches - have never made that work either.  Some of you just have more "vision" than others of us.  So, I'll continue to enjoy my Beethoven in stereo, but my photography in mono.

Mel W.  Columbia, Md.

It takes a little practice to master the "divergent" method.  I've had lots of practice, because most X-ray crystal structures of proteins in research articles are printed for using the divergent method.  The secret is to first focus your eyes on a distant object, then either move the image(s) into your field of view or shift your gaze onto the image(s).  The hardest part is refocusing on the image without crossing your eyes back, since your eyes are focused on the distant point.  I tried the cross-eyed method on these images, but it (not surprisingly) results in a reversal of the perceived depth. 

Had another go, and yes works quite well for me.  Looked at the other examples on the site.

However, I have some difficulty masking out the side images, tend to loose the effect.

Jeff 

Because all antique stereo cards are parallel view (left on left), I learned to free-view them many years ago, and can still do it instantly at will, up to about 7" total width of both views, even though me eyes are old and tired. I have tried cross viewing several times, and sometimes, after half an hour of working, I have been able to see 3D for a few seconds, but it's not an easy or practical way for me to view. Guess younger eyes can do it easier. The few times I have gotten it to work, though, the image has appeared smaller when crossviewed, compared to a parallel image the same print size viewed parallel.

Anyway, am looking forward to new stereo print features in Qimage Ultimate. Maybe I will try to make a "Cutout" to reproduce the look of an antique stereo card of the Underwood and Underwood or Keystone vintage.(The top corners of each image were curved, and there was descriptive text below the right image, and usually the company name on each end of the card.)

Jeff Jessee (the other Jeff)

If you can view parallel views 7 inches wide, you may be the only person on the planet who can!  Printing parallel images 7 inches wide would give 3.5 inches of separation which is well beyond anyone's interoccular distance.  Anything past the distance between the pupils (interoccular distance) requires that you diverge your eyes (opposite of crossing them).  This is not dependent on how far away you view: you'll always have to diverge to see 3D if the print itself has more separation than your eyes.  I don't know a single person who can diverge their eyes.  But I guess there's always a first.

Mike

Some images here, in both views http://www.angelfire.com/ca/erker/gallery.html - Also a link at bottom of page to viewing hints. Plenty of others on web, too.

There are entire groups dedicated to this stuff, with lots of photos.  This is one of my favorite:

http://www.flickr.com/groups/62553512@N00/pool/

Mike

Mike- I just measured the stardard antique Underwood and Underwood cards. The cards, are 7 inches wide, so the photos are a little less, about 6.5 inches wide. I have no problem converging them from about 2 feet away. Guess my head is a little bigger than most, but my eyes aren't 3.25 inches apart, so they are obviously diverging a little. If the pictures are 5 inches wide, it is true that I can view them with less eyestrain. I have seen a lot of other people at the 3D conventions freeviewing the cards, but most of them are old codgers too, so maybe that makes a difference. (Guess we like to look at stuff that's even older than we are.) But they still look a little better in a viewer, as they are magnified. As I'm sure you are aware, the old viewers have a prism effect in the lenses, to converge the images to make viewing easier for the average viewer.

The more modern viewers seem to be designed for viewing 4x6 prints (which they also converge for you), because that's the standard print size. The Loreo camera put the two images on a standard 4x6 shaped print, so that no special processing was required.

Jeff Jessee

Where your 3D will REALLY look good is on a 3DTV. Not all support .MPO files yet, but Panasonic does, just slip in your SD card, and see a glorious 55" 3D scene.

I'm still having a hard time believing this!  Are you sure you aren't crossing your eyes just slightly instead of diverging them?  That would make an image form in the center and even with a parallel view print, it'd still look 3D but it'd look a little "funky".  I tried diverging my eyes today and I still believe it is impossible and that no one can do it!  I have a clear ruler and put my finger up while looking at clouds miles away.  My finger in the foreground showed two fingers about 2.25 inches apart.  There was nothing I could do to make them move farther apart, which you'd certainly have to do if you are really looking at prints where the centers are separated by over 3 inches.

I still think the cross view method is easier on your eyes too!  You really have to force focus to focus your eyes on something close while your eyes are set at infinity (parallel) because the focus of your eyes is linked naturally to infinity when your eyes are parallel.  Much easier to focus close on something closer.

Do a little investigating: I bet you are crossing your eyes and not diverging them.  It'd give a "backwards" 3D view but it'd still have depth and most people would still think it's 3D.

Mike

I have always been able to see 3ds with no problem, although it does induce some eye strain after a while.
Once you get the hang of it, it is easy if you hold your hands out about a foot in front of you and adjust the separation between them,you can mask the side views easily and see the one 3d image.
It was a big fad in poster art in the 90s but quickly died out.

I can free view the old stereo cards in parallel mode with no problem and the depth is normal and not inverted as happens if I use the cross-eyed mode for them. The parallel mode does give a larger image than the cross-eyed mode but is a little harder to fuse the images as another has pointed out.  It does require slight divergence of the eyes, but I've known a number of people over the years who can do it without much effort or eye strain. If I recall correctly, I learned by focusing on something in the distance and then shifting my attention to the card and a single image came into focus. You shouldn't need to strain your eyes to do it -  in fact just the opposite, relax them. For larger images the parallel mode won't work and I have to use the cross-eyed method.

Steve

Well, I cannot do it.!!
Yours truly,

The Cyclops

There's even a Yahoo group called photo-3d that's been around for many years even before Yahoo, and has lots of "stereo" experts who will answer questions you have if you are getting started in 3D. Also, one for just the Fuji 3d cameras (fuji3d), and one for buying and selling 3d stuff (sell-3d), plus several other, more specialized ones.

3D is fun, and it impresses people. The hardest part is viewing and sharing 3D photos with everyone, but as 3D TV's become more popular and support 3D still formats, that will be the easiest way.

Jeff Jessee

Check this out!

http://www.bgr.com/2011/03/22/sprints-htc-evo-3d-hands-on/

Mike