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Sideshoots - associated subjects => The Lighter Side => Topic started by: JayMac on January 08, 2010, 01:15:31



Title: A different kind of picture challenge.
Post by: JayMac on January 08, 2010, 01:15:31
Below are three examples of stereoscopic images I have recently taken. With a little practice they can be viewed on a computer monitor giving a 3D image. Anyone familiar with the technique for viewing 'Magic Eye' pictures should, with a little patience be able to 'freeview' these images without need for a special 'Stereoscope' viewer.

Learning to Parallel Freeview: In parallel freeviewing the image for the left eye is on the left and the image for the right eye is on the right. You stare into the screen so that your eyes are aimed (more or less) parallel. As you stare into the screen you will get double vision as each eye sees the L & R images separately. Relax your focus and try and avoid straining. When you are staring in at the right distance the middle two images will overlap and become 3D. The outer two images will remain and will still be 2D. A simulation of this effect is shown below. I find a viewing distance of about 12-18 inches from the screen works for me.

(http://i598.photobucket.com/albums/tt68/bignosemac/threeview2.jpg)

Don't try to freeview the (above) image. It is just a simulation of what it looks like when you have the proper overlap of the double image. The outside images are shown blurred to simulate the effect you see when staring at the centre 3D image (since your peripheral vision isn't as sharp as central vision).

Now try to freeview the real stereo pair below.

(http://i598.photobucket.com/albums/tt68/bignosemac/parview2.jpg)

Hints: There are several tricks that may help you as you learn. One is to turn up the room brightness until you can see your reflected face in the monitor. Looking at your reflection can help you achieve the proper overlap of the doubled images. Then you need to shift your focus onto the image without having it jump back to 2D (the tricky part :) )

A second trick is to hold a stiff sheet of paper or cardboard vertically between your eyes and line it up with the centre of the image you are trying to freeview. Removing the distraction of the extra images helps some people to learn to freeview.

Success: When the sample image is in 3D you will see the opening around the picture as the nearest thing (called the stereo window). The tree on the left is behind the stereo window but the closest object in the scene. The tree on the right is next further back. Then is the house and furthest is the sun. If you can see all this, congratulations!

Here are the images I recently compiled.

HST at Temple Meads.
(http://i598.photobucket.com/albums/tt68/bignosemac/Picture247c.jpg)

...and again.
(http://i598.photobucket.com/albums/tt68/bignosemac/Picture249.jpg)

Clifton Down Station.
(http://i598.photobucket.com/albums/tt68/bignosemac/Picture244.jpg)







Title: Re: A different kind of picture challenge.
Post by: argg on January 08, 2010, 13:56:34
Nice!

What's the principle in taking the pictures? 
Moving to the left or right or staying on the spot and changing the angle?


Title: Re: A different kind of picture challenge.
Post by: Not from Brighton on January 08, 2010, 16:04:10
Wow that's fun. Better than just about any 3D glasses type arrangement. I'd have not thought it possible that one could control the eye's focal depth and stereo depth independantly of one another!


Title: Re: A different kind of picture challenge.
Post by: Btline on January 08, 2010, 18:41:20
The difficult is that the images to overlap are very big!


Title: Re: A different kind of picture challenge.
Post by: Btline on January 08, 2010, 18:44:56
Wow - just done it! Very effective - never done one using "real" photos before!

My method to get the overlap. Stand away from the screen. Relax eyes and then move forward quickly to the screen. This helps get the images on top, and then the 3D effect just falls out.


Title: Re: A different kind of picture challenge.
Post by: JayMac on January 15, 2010, 17:16:07
My method for taking stereoscopic images is to stand with your feet about 18 inches apart, then put your weight on your left foot by leaning slightly, take the left image, then transfer your weight to your right foot and take the right image. You don't need to exaggerate the movement from left to right, all you need to be doing is to move the camera (on the same horizontal line) the same distance that the centre of your eyes are apart; about 3 inches. One important thing to remember is you cannot capture any movement in each image, so action shots are out. If taking pictures of people you need to ensure they are motionless between taking the left and right image. It's also worth taking the images with objects in the foreground, middle distance and far distance as this gives a better impression of the 3D result.

With a digital camera, compiling the stereoscopic pairs can be done fairly easily with photo editing software on a computer. I find it easier to take the original photos in 'portrait' aspect (i.e. rotating the camera through 90 degrees) as this makes cropping the images top and bottom far easier. 'Landscape' aspect photos need careful cropping individually so as not to destroy the resultant 3D image. Reducing the images down to similar sizes as I have posted helps to make them easier to 'freeview', although some people have sufficient ocular ability to 'freeview' much larger stereoscopes. Everybody's vision is different and what works for one, may not work for another. Apologies to those out there that cannot 'get' the 3D effect, for some it's just not possible to render the images without the use of a stereoscopic viewer.

A few more recent stereoscopes, and in the spirit of more traditional photo quizzes, guesses as to the locations are welcome!

(http://i598.photobucket.com/albums/tt68/bignosemac/Picture004.jpg)

(http://i598.photobucket.com/albums/tt68/bignosemac/Picture018.jpg)

(http://i598.photobucket.com/albums/tt68/bignosemac/Picture021.jpg)

(http://i598.photobucket.com/albums/tt68/bignosemac/Picture032.jpg)


Title: Re: A different kind of picture challenge.
Post by: grahame on January 15, 2010, 17:22:08
My eyes are not what they once were ... so I'm not good with these, but that's a personal things.

The first three locations are hard (he lies).   I suspect the third is between Plymouth and Liskeard, but I would need a further hint to place it more accurately


Title: Re: A different kind of picture challenge.
Post by: 6 OF 2 redundant adjunct of unimatrix 01 on January 15, 2010, 17:34:35
well its deffo not in devon as there is an advertisement for the digital switchover which was compleated in devon last year


Title: Re: A different kind of picture challenge.
Post by: grahame on January 15, 2010, 18:10:10
...  I suspect the third ...

I can't count either. I meant "fourth".  Third is cleary NOT  Saltash, St Germans or Menheniot!


Title: Re: A different kind of picture challenge.
Post by: devon_metro on January 15, 2010, 19:04:11
Judging by the map location on Volo, the 4th picture is Plymouth, the 2nd and 3rd both at Exeter St Davids


Title: Re: A different kind of picture challenge.
Post by: 6 OF 2 redundant adjunct of unimatrix 01 on January 15, 2010, 19:24:35
i recon 4 is taunton 2 and 3  is esd as devonmetro says


Title: Re: A different kind of picture challenge.
Post by: RichieG on January 15, 2010, 21:01:26
Don't think #2 is EXD as the footbridge doesn't look right...  :-\


Title: Re: A different kind of picture challenge.
Post by: JayMac on January 16, 2010, 03:00:33
Judging by the map location on Volo, the 4th picture is Plymouth, the 2nd and 3rd both at Exeter St Davids

All correct. They were rather easy as I'd posted elsewhere about my trip to Cornwall. 2 and 3 were taken at EXD and as we'd had a brisk run from Tivey there was ample time to hop off and take the pics of the 67. Don'tcha just love dwell time?

Sorry relex. 4 wasn't Taunton, I'm avoiding posting pictures of the jewel of Somerset ......4 was taken at PLY as we waited for NR to unjam some points at St Budeaux.

Just 1 to guess. Go on grahame, you said it was easy......


And if anyone out there wants to learn more about taking 'stereo' photographs and the history behind them may I point you to this website:

http://www.londonstereo.com/index.html

Brian May (rock guitarist, cosmologist, author, all-round polymath) was responsible for my new hobby. Please forgive my indulgences.


Title: Re: A different kind of picture challenge.
Post by: grahame on January 16, 2010, 08:02:46

Just 1 to guess. Go on grahame, you said it was easy......


Up at Clifton?


Title: Re: A different kind of picture challenge.
Post by: Brucey on January 16, 2010, 09:34:43

Just 1 to guess. Go on grahame, you said it was easy......


Up at Clifton?
Yes, it is Clifton Down station.


Title: Re: A different kind of picture challenge.
Post by: JayMac on January 16, 2010, 20:34:11

Just 1 to guess. Go on grahame, you said it was easy......


Up at Clifton?

Of course!  ;)



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