Wide-eyed Wonder: an artist's musings on three-dimensional vision

Some are color blind. I am stereo blind.

Archive for the ‘3D computer generated graphics’ Category

Relax. Let go. Give your brain permission.

leave a comment »

I’ve been following this VT patient’s progress reports with interest. Today’s post “Stop trying so hard and just SEE” mentions a common hurdle to diverging our eyes, the ability to RELAX those rogue eye turn-in muscles! “Stop LOOKING” my VT would often say. LOOKING to isolate something normally fixates both eyes on an object, or in my case, unconsciously fixates one eye while turning in and suppressing the out-of-alignment image of the other. “Soften your gaze” was another frequent VT exhortation.

1218randotLast week, random dots did the trick of NOT LOOKING for this VT patient, and I think I understand why. The randomness of the thing viewed eliminates the worry about getting a “right” answer, and therefore is less stressful than “Is the elephant or the fly popping out for you?” which can trigger frantic LOOKING.

Randomness is the opposite of representation, therefore the brain lets go of the need to comprehend and interpret an object. As an artist who strives to accurately represent objects, a good dose of randomness may be exactly what my brain needs to stop trying so hard.

This is why, for me, letting go also requires giving myself permission to allow a new way of seeing to emerge, to be visually open-minded.

I’m rejoicing that random dot stereograms are working for this patient to overcome her eye turn-in along with the many awesome mind-opening exercises her Vision Therapist is tailoring to wake up her brain.

By letting go and giving herself permission to see a new way, her world is opening up into the third dimension I long to experience.

 

Life of 3.1415926535 8979323846 2643383279 etc.

with 2 comments

… that would be Pi

I’d read so much about the artistic use of 3D technology in Ang Lee’s film Life of Pi, I decided it was worth a strabismic test. If I did not see palpable space, with things jumping off the screen towards me, at least I would see art: imagery that would move me and delight my eyes and heart.

I learned something even before seeing the movie: I’m probably the last person on the planet to arrive at a 3D movie only to discover the theater is playing a 2D version! I’d read so much about the artful use of 3D by Ang Lee, that I completely ruled out anyone wanting to see the movie any other way. And so our first trip to the nearest theater in the next town was self-defeating. We went grocery shopping instead.

But, almost two weeks later, Pi resurfaced (with the necessary “3D” listed in the title) in the next town over. (I had given up on Pi and was looking for the Hobbit. But Middle Earth can wait.)

It was good timing for taking in a matinee today, as I had exactly one week to adjust to my new bi-focal lenses with base-right prism (but that’s another story.)

As the film began, the hummingbirds in flight brought an audible thrill to the folks to my left. Ah, but they were too quick for me! And then a short conversation began between my husband and I: “Did you see that? says he. “No” says I. After a few more similar exchanges I said “If I see something, I’ll squeeze your hand.” I believe he got one hesitant squeeze as the monkeys rushed through the trees.

Then I forgot all about how I was seeing as I became immersed in the story.

It was a delightful story with visible layers of foreground, middle-ground and background all moving on their own planes, however if only within the screen for me. More delightful were the even more layers of meaning. Naturally it is easier to take the layers of meaning with me, and enjoy them in my mind long after the visual effects fade away. Ang Lee was masterful in using the concrete layers of the story to enhance the abstract and philosophical.

I had popped sinus medication and ginger pills before the trip, and the seas did get rough! But my stomach did not once drop out from under me. (Suppression has it’s advantages.) I also did not turn green around the gills when the seas turned calm with endless random bobbing. No ginger pills needed, unlike the many times I’ve been becalmed on Lake Erie in my father’s sailboat!

But the “float” stayed with me after the movie.

When everything is floating for two and a half hours, my guess is it does open one’s brain to recognize “float” in the real world.
Dr. Susan Barry describes her experience with “float”, saying “Knowing that objects are separated by volumes of space and perceiving those empty volumes are very different experiences. ”

My first thing to pop out toward me was not the whale in the movie, but my coat, hanging in front of me on a hook in the bathroom stall. It billowed towards me. (My first “sighting” since getting the new lenses.) The bathroom sink faucet took on the familiar forward projection, and doorways and all things moving in my periphery as I walked through the lobby swam in kinetic motion-parallax. A trip to Lowe’s afterwards revealed noticeable depth in the layers of paint chip racks. Empty racks of all sorts reached out toward me, and a small stand of Ohio State banners swam towards me as I walked by, like a school of fish.

I’m floating still.

Links to layers of meaning
Life of Pi: A Novel by Yann Martel By Phoebe Kate Foster http://www.popmatters.com/pm/review/life-of-pi/

‘Life of Pi’ Ending Explained by Ben Kendrick http://screenrant.com/life-of-pi-movie-ending-spoilers/

Links to layers of 3D
Life Of Pi’s Visual Effects Are Extraordinary. Here’s Why by Brendon Connelly
http://www.bleedingcool.com/2012/12/19/life-of-pis-cg-secrets-fx-supervisor-bill-westenhofer-on-tigers-magical-skies-and-more/

How did they bring the ‘unfilmable’ Life of Pi to our screens? by Nick Clark
http://www.independent.co.uk/arts-entertainment/films/features/how-did-they-bring-the-unfilmable-life-of-pi-to-our-screens-8393738.html

Ang Lee On The Filmmaking Journey Of “Life of Pi” By: Scott Pierce
http://www.fastcocreate.com/1682021/ang-lee-on-the-filmmaking-journey-of-life-of-pi

Less than half full

with 4 comments

I lost the moon the other day. When I bent to see it out the passenger car window, the car roof blocked my left eye, but not my right. The moon hid itself in the blind half of my right eye. It was quite a surprise! Thankfully, I don’t normally see things disappear in this way.

It’s been over 3 months since my vision loss from the branch retinal artery occlusion (BRAO) and I am pretty resigned to not regaining my central vision. The blindness in the upper half is a bit more than half, making reading impossible with the affected eye, and eye-teaming by pointing both eyes at the same thing at the same time next to impossible. My tests with the Brock string reveal a partial string in front of the bead that my right eye cannot see without a conscious effort to look above the bead (photo illustration here).

My decision to pursue more vision therapy to gain stereopsis is pretty much settled: if I could read with the right eye and see the Brock bead easily, I would go for it. But alas, I cannot. When it comes to seeing 3D, my glass is less than half full.

I do have one friend who has urged me not to fully resign myself to permanent loss until six months have passed. He also had BRAO and regained more vision in months 4-6. However, the retinologist said the ischemic tissue would resolve in about 3 months, so I’m mostly resigned at this point.

And so I have begun to grieve a bit. When watching the best documentary of Dr. Susan Barry’s (aka “Stereo Sue”) story yet (Imagine: The Man Who Forgot How to Read and Other Stories, Part 3 beginning at minute 11) I felt that I would never be able to see the front end of a Toyota (minute 14:14) with anything close to her jubilation over it’s roundness … I got misty-eyed when the film ended with Oliver Sacks sadness over his stereo loss (Sue’s gain is compaired to Dr. Sack’s loss in part 4). That night the family cat breathed her last, and the next morning the torrents flowed over the dual losses. My husband was relieved to see me cry, finally.

My self-portrait is another step in the grief process. Today, I took advantage of the cracked side of the mirror and left the top of my head in a vignette to illustrate not so much what I see, but how my impairment can feel at times. I’ve felt the need to do this portrait before pursuing my art again. (I still can’t make a nose pop out like it should!)

The good news is that my brain has smoothly pieced together a complete visual field. I actually do see a near-complete picture without wrinkles or cracks, but sadly, this is because my right eye is almost fully suppressed. I am a master suppressor, having suppressed my left eye for no real reason all my life right up to March 26th. I was beginning to overcome this rogue suppression when the BRAO hit. Now, ironically, suppression is helpful.

I only see my blind veil when the left eye is occluded by the bridge of my nose, most often when I turn to look behind my right shoulder to back up the car. At those times, I rely on my recently learned ability to look above what I need to see. Nothing is clear, but movement and large objects can be detected out of the corner of my right eye. Needless to say, I avoid backing up the car as much as possible, and do so very slowly when I absolutely have no choice.

I frightened myself passing a box truck last week. I felt way too close to the truck when I quickly got back into my lane after realizing the oncoming pickup truck was much closer than I had first determined. I felt it was a close call, and I’m sure the other drivers thought I was out of my head!

When not encumbered by driving, my summer hours in the outdoors have been delightful. I attribute this to a ramped-up sense of motion parallax. This week, picking blueberries and pruning are challenging my brain and eyes to orient myself in space. These are visually demanding situations where “where” is more important than “what.” When I make a move, the branches of bushes and trees diverge and converge just like a 2D video game. What fun! I also routinely search for and destroy the random leaves of returning poison ivy with carefully aimed squirts of herbicide, first-person shooter style.

Inside the Northern  Laurel Oak

I really sensed space inside my magnificent Laurel Oak, but alas, a photo doesn't capture volumes of air.

Occasionally, I thrill over my sense of what Susan Barry calls “palpable space” as well as the heightened textures of grass, weeds, and even asphalt. This is probably because I am seeing the world through my “other” eye and the viewpoint and perspective are new. While hanging laundry, I truly sense the space between the moving clothes-lines and pins. Sometimes, I am enchanted by the hollow spaces inside trees, and the “float” of the lily pads on my pond. I can see “under” the wire mesh deck table when I bob up and down in my deck chair in the evening cool. I see the space inside my coffee cup (this I consider to be true stereo). It is all a delight to my inner child.

So much of the world in my new, 5-acre homestead (photos here) is a rediscovery of childhood delights: stars at night and glorious moonshadow; weeds I haven’t seen since childhood blooming in delicate flower at the edges of the pond. We even have bats at sunset, that swoop over the pond in amazing aerobatics as they scoop up their insect meals: another childhood memory from my Nana’s summer cottage in New Jersey. When a cold front comes through, the clouds dance over the house and fields …

I can still be amazed at everything I see. I still SEE, and so my half-empty stereo-vision cup overflows.

3D gaming and esophoria risks

leave a comment »

In a Wall St. Journal article last Friday, it was reported that a professor in the Department of Ophthalmology, Osaka University Medical School, Japan will be studying whether children with esophoria, the tendency for the eyes to turn inward, will become at risk of more turn-in with prolonged 3D gaming.

Takashi Fujikado, a visual-science professor at Osaka University’s Graduate School of Medicine, is starting research on whether children afflicted with esophoria, who are constantly making extra effort to prevent their eyes from becoming cross-eyed, may find it difficult to return the eyes to normal position after watching 3-D images for a long period of time.

When a 3-D image pops out from a screen, it draws the eyes inward to focus on an object that appears closer. This may affect children six years old and younger because their eyes, still under development, are more sensitive to such stimuli, he said.

Children with such a condition are rare but it is difficult to determine how many there are, Mr. Fujikado said, because esophoria doesn’t necessarily have symptoms.[1]

I have a hunch that what Dr. Fujikado is looking for is whether the esophoria may develop into an esotropia, where an eye constantly or alternately turns inward. Alternating esotropia is the strabismus I mysteriously developed as a child, unknown to my parents and undetectable in photographs.

Visitors try Nintendo's 3DS players at Nintendo World 2011. —Bloomberg News

Esophoria is not a form of strabismus. It is “A muscle condition in which, when both eyes are open, each eye points accurately at the target. However, upon covering one eye the covered eye turns inwards. Also known as over-convergence.”[2]

Esophoria can be picked up during an eye exam with a cross-cover test that breaks fusion. Watch the differences between exotropia and exophoria here. With esotropia and esophoria, the deviating eye would snap back into alignment from the nose, not the ear. (Note the extreme solution of surgery is for tropias of a certain kind that cannot be corrected with vision therapy or orthoptics.)

Unlike esotropia, fusion is possible (with esophoria) and therefore diplopia (or seeing double) is uncommon.[3]

Donald J. Getz, OD, FCOVD, FAAO explains another sign of esophoria [4]

“… a child with esophoria sees things smaller than what they actually are. In order to see an object properly, it is necessary to make the object larger. The only means at the disposal of the child to make it larger is to bring it closer. Eventually, the child is observed with his head buried in a book… ”

Photograph: Frank Baron

3D Movies and Stereoblindess

leave a comment »

Hi, I’m just curious … I don’t see 3D. Would it be possible for me to get a glimpse of your 3D movie and find out what I can see?

I asked this only after purchasing tickets for the 2D version of Narnia: The Voyage of the Dawntreader Afterward, I and my friends shared a pair of glasses to briefly check out the 3D difference.

Even though I didn’t get the “Wow!” of an object jumping off the screen or moving behind the screen that my friends saw, I would still pay the extra bit to see the richness of detail the new polarized glasses create. Everything was clear, and not a blur (which happened often in the 2d version. Thoughts on why later.)

With polarization, which cuts out some glare, I saw deeper colors. [1] I studied the golden shell Edmund pulled from the pool of gold, and it appeared richer to me, even though it was not 3D. Instead, it was similar to what I experience when I see a painting by that rare artist that can translate 3D to a canvas, such as my friend and portrait artist Judith Carducci.

Unlike legacy 3d movies that required the red-cyan glasses, the new technology uses a different kind of fusion. Legacy film 3D required two projectors running film perfectly in synch, shot with cameras that had to be aligned according to a precise geometric formula during filming. [2] One camera filmed through a cyan filter, and the other filmed through a red filter. The red-cyan glasses worn by viewers would cancel out the conflicting image and the binocular function in the brain’s visual cortex would fuse the two images from each eye to create 3D. [3] It was an imprecise method and never caught on, as every imperfection would create literal headaches.

Furthermore, the stereoblind, who could not bring the non-conflicting images together with one-eyed viewing, experienced a movie that was either completely red or cyan!

The new technologies are digital. No film is used. The two cameras that do the “filming” to digital files are precisely aligned with a computer. [4] Digital post processing of CGI effects is also rendered with 3D formulas. (In the case of Dawn Treader, only the post processing was 3D. Two cameras were not used to shoot the live action. [5]) The left and right integrated “film” file is shown through only one projector, as the input from both angles is digitally fused into one movie. [4]

Both RealD and Dolby 3D projection systems use a rotating high-speed alternating filter. Left and right images alternate so quickly that the brain takes them in through the Dolby optically coated or RealD polarized glasses as one continuous image. The coatings or polarization in the glasses cancel out the conflicting alternate images in each lens. [6] [7]

What this means for the steroblind is only every other image is seen through either the right lens or the left. There is no haloing or ghosting because the opposite image is blocked by the same lens the dominant eye is using.

This is good news! No ghosting! No red or cyan viewing!

Eye problems, even with the 2D version

The newer 3D movies rely on extraordinary optical flow and motion parallax. The rapid CGI rotation and camera panning appeared blurred or jerky to me in the 2D version, annoyingly so, because all my depth cues were put on steroids. It was like watching a home video where the would-be videographer didn’t know how to pan his camera. If these scenes had lasted any length of time, I would have needed to avert my eyes to avoid nausea, a common problem I experience due to lack of stereoscopic ability.

All of the film’s CGI sequences appeared jerky, like watching a video with a slow internet connection. At the end of the film, during the credits, the background had a very annoying flicker. I wonder if this is because the producer did not bother to create alternate 2D CGI? The film underwent 8 months of 3D post processing. [5] Making alternate 2D CGI sequences may not have been in the budget, especially if the producers thought the 3D ghosting or haloing and alternating flicker would not be noticeable to most viewers.

Secondly, much of the film was was shot with a lack of depth of field, especially during the layered action scenes onboard the ship. Because I am steroblind, relative size relationships and perspective behind and before the action were out of focus. I felt somewhat lost and annoyed without these depth cues, as I was constantly subconsciously attempting to bring the whole scene into focus.


In this image, Lucy’s face is in focus, but the painting and Edmund are not. This is due to the way the scene was shot, with a lack of depth of field.

All this points to a dim future for the stereoblind movie-goer, as every 2D version of a 3D movie is not going to be as easy to watch as the simple 2D movies of old.

RealD polarized or Dolby coated glasses would cancel out any 3D flicker that may be embedded in a 2D version, but how to find out if 3D sequences are in the movie? Would the ticket person be able to hand out the glasses for 2D movies if asked? Probably not. Better to spend the extra 3 bucks and just watch the 3D version with the same flatness I see in real life.

At least I am improving my peripheral awareness to enjoy the pumped-up optic flow and motion parallax that these new films are dishing out.

Links to the technology of 3d movies for further exploration

Popular Mechanics “The Tech Behind 3D’s Big Revival” April 2009 http://popularmechanics.com

“JDSU Shares Science Behind 3D” http://www.youtube.com JDSU is the company that developed the coatings for Dolby 3D. The commentator offers some lame misinformation, as his competitor’s polarized glasses are being recycled at movie theaters and not thrown into landfills.

“To 3D Or Not To 3D: Buy The Right Chronicles Of Narnia Ticket” http://www.cinemablend.com offers a sub-par 3D analysis of the film, as the reviewer says at one point that it didn’t matter if she saw the film with the polarized glasses or not. I’m sorry, but in any 3D film, the glasses cut out the bothersome ghosting. This reviewer must have grown up with poor TV reception in West Virginia.

Tech info on RealD from wikipedia

RealD 3D cinema technology uses circularly polarized light to produce stereoscopic image projection. Circular polarization technology has the advantage over linear polarization methods in that viewers are able to tilt their head and look about the theater naturally without a disturbing loss of 3D perception, whereas linear polarization projection requires viewers to keep their head orientation aligned within a narrow range of tilt for effective 3D perception; otherwise they may see double or darkened images.[2]

The high-resolution, digital cinema grade video projector alternately projects right-eye frames and left-eye frames 144 times per second.[2] The projector is either a Texas Instruments’ Digital Light Processing device or Sony’s reflective liquid crystal display. A push-pull electro-optical liquid crystal modulator called a ZScreen is placed immediately in front of the projector lens to alternately polarize each frame. It circularly polarizes the frames clockwise for the right eye and counterclockwise for the left eye. The audience wears spectacles with oppositely circularly polarized lenses to ensure each eye sees only its designated frame, even if the head is tilted. In RealD Cinema, each frame is projected three times to reduce flicker, a system called triple flash. The source video is usually produced at 24 frames per second per eye (total 48 frames/s), which may result in subtle ghosting and stuttering on horizontal camera movements. A silver screen is used to maintain the light polarization upon reflection and to reduce reflection loss to counter the inherent losses by the polarization filters. The result is a 3D picture that seems to extend behind and in front of the screen itself.[3]

Tech info on Dolby 3D from wikipedia

Dolby 3D uses a Dolby Digital Cinema projector that can show both 2D and 3D films. For 3D presentations, an alternate color wheel is placed in the projector. This color wheel contains one more set of red, green, and blue filters in addition to the red, green, and blue filters found on a typical color wheel. The additional set of three filters are able to produce the same color gamut as the original three filters but transmit light at different wavelengths. Glasses with complementary dichroic filters in the lenses are worn which filter out either one or the other set of three light wavelengths. In this way, one projector can display the left and right stereoscopic images simultaneously. This method of stereoscopic projection is called wavelength multiplex visualization. The dichroic filters in the Dolby 3D glasses are more expensive and fragile than the glasses technology used in circular polarization systems like RealD Cinema and are not considered disposable. However, an important benefit of Dolby 3D as compared to RealD is that no special silver screen is needed for it to work.