Issuu on Google+

Designing with Light Designing in Space

Researching the designing capabilites of Light with emphasis on Spatial construction via the use of light sources Design Portfolio Keranis Michail - Karolos MArch Graduate Architectural Design, 2011-2012 Bartlett School of Architecture, UCL Research Cluster 5 Tutors: Andrew Porter, Luke Pearson, Godofredo Pereira


Preface Our perception of architectural design derives directly from our perception of space. It is also a fact that we perceive space by its’ interaction, and ours, with light. To me light is a designing material and that is how I approached it in my research. By designing with light I would be able to better understand its qualities, attributes, as well as, capabilities as an instrument for creating architecture. For designing in space. My research has to do with how light may alter our perception of an existing space (its’ volume or shape, purpose or use, character or even meaning), as well as, how light, natural or artificial, can be utilized to grant a certain atmosphere, which aids the observer to discover alternate qualities in an existing space and completely transcend his basic perception of it. These particular qualities of light, these unique attributes are what I decided to research and try and incorporate into a designing methodology. Another aim of this project was to work with light as a direct architectural material and fully utilize it in a direct designing manner. This particular aim led me in the use of light painting. Upon the completion of this project, I believe i have managed to create a new designing methodology. One which, with its’ unique structure and spatiality, will be able to serve as a research tool in the fields of notation, mapping and, of course, original design. My second goal with this project was be able to make a statement; that the way in which we perceive space may be accurate, but it certainly isn’t the only way. And that light is able to reveal and create a hidden, mysterious and almost sublime atmosphere. 1. Personal Work, Initial Test with an LED Strip

page. 1


Table of Contents • Preface ..........................................................................................................pg.1 • Initial Research .............................................................................................pg.4 • Light Painting Testing .....................................................................................pg.6 • The Adhoc Instument....................................................................................pg.10 • Doors of Perception.....................................................................................pg.16 • Video Mapping, Digital Light Painting..........................................................pg.20 • The Architectural Notation...........................................................................pg.22 • Vessels of Light, IVA Velux 2012....................................................................pg.34 • The Apparatus.............................................................................................pg.36 • Space in Light..............................................................................................pg.40 • Project Proposal: Shedding Light over South Bank Centre...........................pg.52 • Bibliography ................................................................................................pg.76

page. 2


2. Personal Work, Woman Walking, Light Painting Diagramm on the Human Body Movement

page. 3


Initial research During the beginning of my research I was trying to find ways to depict the sublime, almost ghostly atmosphere created by the interaction of light with a semi-transparent surface, and figure out ways of recreating it. I decided upon working with a mathodology that would try and isolate the Play of Shadows that appears almost exclusively in the threshold where light and dark meet and interact. I was able to draw the choreography of light and darkness as they interact with each other and the existing space while shifting through it in an endless competition between the two. The result were a series of drawing upon an existing space, loosely based on the art of a japanese Ink painting. The choreography between the two elements was evident, however, the basis of design and the stimuli by which they were created were lacking. Despite that, the notions of choreography, design upon an existing space and interaction of light and dark, as well as, the clear goal which was the designing of the sense of the sublime within a space, were the basis of my later research, my involvement with Light Painting and Spatial Design. 3. Personal Work, Light and Darkness, Ink Drawing on Photograph

page. 4


4. Personal Work, in Praise of Shadows, Ink Drawing on Photograph

page. 5


Light Painting Testing In the earliest stage of this project I had to get accustomed to the process of light painting, figure out the technique and how it worked. I proceeded by making a series of tests with a camera capable of long exposures and a normal flashlight. After figuring out the core mechanics of the process I realized that in order to create a better sense of space with light painting I need to enrich my palette of tools with light sources of different size, shape, colour and brightness. The immediate next step was to get accustomed to these tools, realize their potential and designing capabilities and assign them with roles, or rather designing tool equivalents, according to that. To give an example, after testing I realized that LED flashlights would serve better as a tool for designing lines and curves due to the strong and solid light they emanate and their very limited (close to zero) glare effect that the lens captures as a milky fog effect around the trace of the line. To this point my light painting process was a completely gestural procedure following the movement and anatomy of the body. A very interesting, in terms of research, procedure yet highly crude as a designing methodology and with the ambiguous attribute of being a non-recurring series of gestures.

5. Personal Work, Initial Test with an LED Strip

page. 6


6 & 7. Personal Work, Initial Tests with a flash light, 30 seconds duration of the Shot, Iso 200, F 22

8 & 9. Personal Work, Initial Tests with a flash light and an LED strip, 30 seconds duration of the Shot, Iso 200, F 22

page. 7


10 & 11. Personal Work, Tests with a LED Torch and Glowstick, 30 seconds duration of the Shot, Iso 200, F 22

12 & 13. Personal Work, Tests with a Lightsaber, an EL wire and a Hoola Hoop, 30 seconds duration of the Shot, Iso 200, F 22

page. 8


14. Personal Work, Light Painting Test with Glowsticks, 30 seconds duration of the Shot, Iso 200, F22

page. 9


The Adhoc Instrument At this stage I discovered that the use of ordinary, mundane objects as light painting tools produced extremely beautiful and, more importantly, really interesting and spatial results. So, I proceeded into using more adhoc tools: a skateboard, a curtain-rail, a fan. It is also important that during this new spatial experience that I was trying to design, the everyday object became a designing tool and proposed its’ own methodology. Needless to say, that the human body itself is to be considered an adhoc instrument. Thus, the combination of the mundane objects’ repetitive and standardised movement and use with the performative actions of the human body enhanced and completed the gestural experience of light painting in both end result as well as designing process. The process became more refined, more repeatable, more spatial without reducing the bodys’ performative actions which are the core of the spatial experience during the light painting procedure.

page. 10

15. Personal Work, Test with a LED Torch strapped on a broomstick


16. Adhoc Tool, Skateboard and Pole

17. Personal Work, Test with an LED Strip and Torcj strapped on the Skateboard Pole

page. 11


19-23. Personal Work, Test with the Hoola Hoop and various Light Sources

page. 12

18. Adhoc Tool, EL wire strapped on a Hoola Hoop


24. Adhoc Tool, Fan with glowsticks and various other light sources strapped onto it

25-30. Personal Work, Experiments with the Fan Adhoc tool on a loose as well as a sturdy base

page. 13


31. Personal Work, Light Painting with glowsticks and a fan

page. 14


32. Personal Work, Explanatory Architectural Drawing of the Fan Light Painting

5262

8 00 i so

22

18

11

2

0

f

0

5

10

15

20

25

30

t 0

7441

page. 15


Doors of Perception After creating the augmentation instruments and feeling comfortable about my light painting technique I decided it was time to work with light and create spatial compositions that would explore the particular quality of light to alter our perception of an existing space. After choosing a location with which most people are familiar with, a regular living room, I applied my light painting technique and created a series of pieces that granted different spatial conditions in that existing space. Each composition aimed in granting the same space alternate qualities and a totally different atmosphere while exploring the ability to design in space.(fig.8-13) In order for the experiment to work and the results to be accurate a series of rules had to be applied. First, the existing space was photographed from the exact location and under the same conditions in every single shot. Second, the thirty second rule was applied. Due to the continuous absorption of light by the lens during a long exposure shot, the longer the duration of the shot, and therefore the light painting process, the brighter the light sources and the existing space would appear. In order to avoid that I applied a thirty second rule on the duration of each shot, duration during which, after previous testing, I was feeling comfortable I would be able to complete a series of gestures that would be sufficient for communicating the new spatial conditions I wished to grant in each composition. The third and final rule I applied in this series of light paintings as well as in all the testing that preceded them, was that no means of digital manipulation would be applied on the end result of the light painting process. Thus, the results would be accurate and would lead to useful assumptions for the works that would follow. During the same period in which these spatial compositions took place I was highly influenced by Hans Hollein’s statement that “everything is architecture” after which he proceeded into making a series of projects that invoked everyday objects as a replacement for architecture 2, thus granting new meaning in the term architectural space. During the same time Reyner Banhams’ “A home is not a house” essay and especially the images by Dallegret of the Power-Membrane House which introduced a new mindset in what should be considered habitable space, and therefore architectural space were a valuable inspirational material to me. (fig.14-17) Highly influenced by the way Hans Hollein and Reyner Banham addressed the notion of space I proceeded to create a series of compositions that referred to the same matter and in the same terms only through the use of Light Painting and its quality of designing in space.

page. 16

33. Personal Work, Interpretation of Francoi Dallegrets’ “Art Fiction1”


34. Personal Work, Doors of Perception 1

35. Personal Work, Doors of Perception 5

36. Personal Work, Doors of Perception 2

37. Personal Work, Doors of Perception 4

page. 17


38. Personal Work, Interpretation of Francoi Dallegrets’ “Power Membrane House”

page. 18

39. Personal Work, Interpretation of Francoi Dallegrets’ “Art Fiction2”


40. Personal Work, Interpretation of Hans Holleins’ “Architectural Space”

page. 19


Video Mapping, Digital Light Painting My research led me to video mapping, a technique that essentially uses digital light, projection, to grant the viewer with the effect of space manipulation. Video Mapping is a projection technique used mainly my video artists to create the illusion of immediate space alteration. Its most often used variation is that of façade manipulation. With the use of certain softwares (VPT, vvvv, Resolume) that allow the manipulation of a projected image or animation on the façade of a building, one can give the two-dimensional surface threedimensional attributes, such as depth, shadow, spatiality and mobility. The most important factors for the illusion to work are the precision of the projected image onto the façade along with the location of the observer. Video Mapping has been mainly used for shows by artists called Video Jokeys (VJ), however artist groups like “AntiVJ” and “Light Harvest” have been using Video Mapping to explore the spatiality of designing with light with a series of interesting projections onto three-dimensional objects, void spaces and different materials. Light Installations such the “3Destruct” and “EYJAFJALLAJÖKULL” by AntiVJ act as clear statements of the ability of light to create space in reaction to space it inhabits in a very fascinating and contemporary manner. After observing the use of the technique by others and considering its capabilities as a designing methodology, I proceeded into a series of tests that would allow me to get a better understanding of video mapping. First of all, I created a series of animations, which I later on projected into a flat surface, trying to imitate the technique of façade manipulation. My goal was to create the illusion of three-dimensionality on the flat surface of the wall. Although this series of tests was considered unsuccessful (the illusion of three-dimensionality didn’t work as intended), they provided me with enough data to realize what was needed for the technique to work and whether I could utilize it, to its full extend, in my own research. In the latest stage of my Video Mapping research, I worked with a software that would allow me to project in three-dimensional objects and manipulate the projected image to suit my purpose of spatial design. With this technique at hand, along with light painting which would always remain my key designing methodology, I would try and proceeded into forming an overall proposal that would cover the process of designing with light in a complete manner as well as make a statement about the importance of light in understanding the structure of space, and therefore that of architecture.

page. 20


0:06

0:12

0:18

0:24

0:30

0:36

0:42

0:48

0:54

page. 21


The Architectural Notation The second part of my research involved a series of trials by which I was trying to link the light painting technique to that of an existing architectural designing methodology. I discovered that the best way in which this could be achieved was in the field of notation. I produced a series of light paintings in which I was trying to design qualities about existing spaces that weren’t obvious in the naked eye, such as movement, lighting patterns (natural and artificial), the space objects and people actually occupy etc. I then tried to use the new elements as a basis by which I would re-design the existing space.

G13 The first space I experimented on was G13 inside the building of the Bartlett. Like any common room inside the building, G13 is a rather neutral space able to accommodate any sort of tutorial procedure. Its’ only different characteristic are the two wall-size windows that inhabit the rear of the room (one placed opposite to the other) that allow sunlight to enter the room during daytime. The reason I chose this room was that for my first experiment I wanted to design a spatial composition, a notation, directly driven by the forms that light, artificial and natural, creates upon entering a space; and G13 was ideal for that sort of experiment. I used light painting and designed the forms as I saw them and recorded myself during the process in order to realize and be able to better explain my work. After completing this procedure, I used the resulted light painting as a plan to form shapes that would inhabit the space. Like in Kurt Schwitters’ Merzbau, a Grotto of formations appeared. It was, however, a different type of grotto. This time the architectural intervention that took place derived directly from the formations of light that previously inhabited the space, yet were only visible and three-dimensional through the light painting. The differences between Schwitters’ Merzbau and the “Light grotto” in G13 are visible in methodology, designing process and, finally, in the observation of the outcome. The next step was to use video mapping in order to project light patterns on top of the artificial grotto to further enhance the design, into an ever changing topology, created by the shift of light movement in space.

page. 22


page. 23


page. 24


G01 The second experiment I performed involved the most commonly used room of the Bartlett building, G01. G01 is mainly used for presentations, lectures and workshops, thus it is a room inhabited by a large amount of people at the same time. During this designing process my aim was to design the “extra-space”, the space that each tool, device, furniture and person inhabits inside this room, which, although invisible, is very different than the physical volume of their size. It consists of a “comfort-buffer” zone which people and objects inhabit. One would assume it to be “a personal space within space”. I worked on the space after it had been used for a workshop, leaving all the furniture untouched, as I had found them. Once again, I recorded myself during the process, yet this time I also tried something different. Just like in conventional architectural design one plan is not always enough to convey the necessary information, I figured I should try capturing multiple frames of the same light painting process. That way the amount of information deriving from a series (and not just one) light paintings would be greater and much more accurate. This time my design methodology was that of mapping the space. I used a variety of light sources to map the existing objects inside the rooms as well as the “comfort-buffer zone” that I considerer they inhabit. I also tried to map the movement of people about the space during the workshop. The way the furniture was left, pointed out which ones were more commonly used, which were inhabited and suggested a certain movement pattern about the space. All this qualities I tried to depict in space by using light painting.

page. 25


page. 26


page. 27


Room Panorama This experiment was performed in my own apartment. My aim this time was to create a light painting that would achieve a level of detail similar to that of architectural plans. I needed to prove that light painting was capable of designing in such detail, so I decided to use a space I was most comfortable moving in and had great experience of. I, again, followed a mapping process in the way that I approached the existing space though this time I wished to enhance the level of three-dimensionality of the light painting by creating a more dynamic result. For this reason I included another photographic element onto my technique; that of the panorama shot. A panorama shot includes more information and spatiality in a single frame and when analyzed into a drawing (which was the main aim of this exercise) it comes up with a very dynamic final outcome.

page. 28


The product of this procedure was highly detailed, yet it was still inferior to a conventional architectural drawing in that aspect. This allowed me to realize that in order to achieve a higher level of sophistication I need the aid of a machine capable of reaching it (a thought that had been crossing my mind for a while now, yet had finally been solidified).

page. 29


page. 30


page. 31


Under the Bridge My last experiment was, in my mind, the most daring and frightening. With no existing space as a canvas, no feedback, I would try to create an original design in open space. I chose a location by the Camden Canal and had a bridge crossing above me act as a limit of the area I would design in. My goal was the same as in the previous experiment; to achieve a level of detail equal to that of a conventional design. With the lack of an overall existing space and feedback between myself and the space, this goal become even harder to achieve, thus proving my previous observation that I needed some sort of mechanical aid to have better results. However, this test proved, much to my delight, that original design is manageable with the use of light, and light painting in particular.

page. 32


page. 33


International Velux Award 2012 “The Light of Tomorrow” Competition for Students of Architecture, issued by Velux in 2012 Team Project “Vessels of Light” in collaboration with Vasilios Chlorokostas and Margarita Koulikourdi The competition for the International Velux Award of 2012 required the creation of a design which would take into consideration the capabilities and attributes of Light, natural and artificial, and highlight them in a project proposal. We decided to use Light Painting as a means of creating notation drawings and diagramms that would explain the intention behind the project and at the same time “celebrate” light in a different way by pointing out its’ designing capabilities. These notations communicate the idea of light creating a vessel that will interact with the interior and exterior of the building, thus playing a major role in its appearance and form, which exceeds the usual use of common openings in the facade of the building for lighting and ventilation purposes.

page. 34


page. 35


The Apparatus The research and testing behind the form and function of the apparatus was, in essence, a research in computation, automation and repeatability. A construct or a series of devices that would incorporate the above elements and, while combining them with the freedom of movement of the human body, fuse them into a designing methodology that would achieve the goal of redesigning and reforming space with the use of light. Thus, a new series of tests begun, with the aim of understanding how computation, automation and repeatability can be incorporated into a light designing methodology. The earliest experiment, and the most analogue of this series, was a direct approach in researching repeatability. By “borrowing” the basic methodology behind light projection, which was investigated during my previous research on video mapping, I designed an immovable string construct that occupied a large amount of space and projected on it light from a close-quarters light source. By repeating the process multiple times and comparing the results it became fairly obvious that light projection could easily produce the same end result, due to the target object being immovable, despite the light sources’ irregular movement. The process however, was lacking in achieving automation and the methodology behind it wasn’t on par with the one that has been researched on thus far, which involves spatial design and not projection of an existing built form. Despite that, this process could prove useful as an addition in the original methodology of light design, by altering the perception of an existing space or construct in space, with targeted light projection, just as video mapping had revealed in previous experiments.

page. 36


page. 37


The second experiment involved the use of a computer-programmed robotic arm. The robotic arm could perform a series of motions, that mimicked the movement of the human arm, while holding a small light source, and could be programmed to perform the exact same motions an infinite amount of times. Essentially, the results of this experiment proved that the elements of computation, automation and repeatability had been successfully incorporated, however, the designing capabilities of the robotic arm were severely lacking due to reach, versatility and movement complexity. Therefore, it was able to create a more restrained and limited range of spatial light designs, that could not compare to the freedom and variety that the performative action of the human body could provide, despite it proving to be more accurate as a gestural movement. (fig.38-41) Despite its’ limitations, the logic behind the movement of the robotic arm, would act as the principle behind the movement capabilities of the original apparatus and its’ computer software platform would be the basis by which the final design would function. It was also understood that a single device would be insufficient in providing the complexity in movement and spatiality that was sought. A series of devices acting as an installation piece, easily adjustable to any environment, and which could co-operate with the human body, or augment it, had become the clear goal in the design of the apparatus.

page. 38


page. 39


Space in Light The beginning of the last term was a trial for me. I needed to figure out ways in which to progress my technique as well as come up with ways to utilise the light paintings as a source for architectural design. Progressig the technique happened by re-instating the concept of time. Thus far the concept of time in my work was that time was considered still, frozen, in a single moment, the end result. Althought the performative aspect of the technique played a major role in both experiencing as well as redesigning space, the performance, the key moment in which it occured was not present in my Light Paintings. Video Light Painting allowed me to change that by keeping the timefactor present as well as allowing a visible end result. The architectural design via the use of light painting is the collective experience of all the above. The performance, the inhabiting of a space, the notation of behaviour within a space. How we move, how we interact, how we feel are all important factors that we experience dailyin our own occupation of any space, and are elements present in a light painting, which if read correctly can be a form of design by which we can draw important data and can be further used to propose a new space, a new architectural designing methodology.

page. 40


page. 41


page. 42

0:02

0:04

0:06

0:08

0:10

0:12

0:14

0:16

0:18


720

iso

22

800

18

11

2

0

f

0

3

6

9

12

15

18

t 0

1280

page. 43


page. 44

0:04

0:08

0:12

0:16

0:20

0:24

0:28

0:32

0:36


 Light Painting Settings: - Shot Duration: 30 sec - Apperture (f): 22 - ISO sensitivity: 200 - Image Quality: 7016 x 4663 pixels

4663

22

iso

200

4m

4m

18

11

4m

2

0

f

0

5

10

15

20

25

30

t 0

7016

page. 45


page. 46


page. 47


page. 48

0:02

0:04

0:06

0:08

0:10

0:12

0:14

0:16

0:18


page. 49


page. 50


page. 51


Project Proposal: Shedding Light over South Bank Centre

How does one design architectural principles of equal importance to form or function? How does one design atmosphere? Harmony? Order and Chaos? How does one create designs that convey feelings? Ideals? Events that occur, have occurred or are going to occur? These were some of the questions I set upon myself in the beginning of this research. I tried to answer them by researching the designing capabilities of Light. My research has led it me to this fact: Designing with light and more specifically light painting as a spatial gesture may convey some of the above principles. It can design another form of architecture. That of Architecture as Event. My project proposal is to try and convey that architectural aspect of the city of London, or part of it. The ephemeral architecture that light can reveal, interacting with the existing one. A designing methodology that becomes a comment on behaviour in space. By designing with light I would be able to express upon the most spatial, actual, canvas, the city itself in ways that the naked eye may not be able to see, yet the brain and our spatial experience may interpret. As Tim Boucher commented on Sarah Wiggleworths’ and Jeremy Tills’ “dinner table” “ways of doing things which are typical and which tend to work according to the people who most commonly perform the activity, in question” and redesigned our dining rooms, table cloths, and place setting accordingly. And thus, by series of localized interventions, a series of light paintings, I would redesign the city of London. By utilizing the capabilities of the finalized model of the apparatus I am able to bring forth light paintings’ full potential as an architectural gesture. The apparatus would work, in combination with the performer-designer (who essentially, becomes part of the apparatus himself) in the broader spectrum of the city and be able to design the events, the actions occurring in every selected space, whether that is London Bridge, Camden Market or the South Bank Centre during the Olympics, which would be portrayed as a completely different architectural space at the time since this designing methodology is highly circumstancial and event dependant. These immaterial traces of movement, occurrence, event and feeling, or atmosphere, create a completely different view of an otherwise familiar space. As far as the final outcome is concerned, the last step of the process contains the placement of the spatial “reading” of every given location back on site, through the designing capabilities of the apparatus, with the intention of creating a dialogue between the ephemeral architecture of light and the existing one. A revelation that both exist in the same space, both add their architectural values into it and both can, via the use of the apparatus – philosopher be designed. Platos’ Cave is finally complete as a designing methodology. A methodology that blurs the distinction between the “seen” and the “unseen” and forms a combination of the existing spaces and the events occurring in them.

page. 52

The South Bank Centre Project Southbank Centre is a complex of artistic venues in London, UK, on the South Bank of the River Thames between County Hall and Waterloo Bridge. It comprises three main buildings (the Royal Festival Hall, the Queen Elizabeth Hall and the Hayward Gallery), and is Europe’s largest centre for the arts. It attracts more than three million visitors annually. Nearly a thousand paid performances of music, dance and literature are staged at Southbank Centre each year, as well as over 300 free foyer events and an education programme, in and around the performing arts venues. In addition, three to six major art exhibitions are presented at Hayward Gallery yearly, and National Touring Exhibitions reach over 100 venues across the UK. The South Bank Centre is also a complex of significant architectural value. A clearly brutalistic, in form, complex, the Centre was an original experiment in British architectural design by some of the most daring thinkers of the 1960‟s – including Archigram‟s Ron Herron and Warren Chalk. During the duration of the 2012 Olympics held in London, the south Bank Centre was in a constant morphing stage. Different happenings on a daily basis, art installations that only lasted for a few days, sometimes even hours and, of course, an ever-changing crowd of people inhabiting the area and experiencing it in all different possible ways. Tourists, walkers passing by, skaters mis-using the building, artists setting up their pieces etc. This constant state of change, this endlessly morphing architecture is what I would try to design in my final project. Events that exist only for a few moments and then are gone, are now depicted into light paintings and videos that reshape them, re-imagine the whole spatial experience in a celebration of the artificial world of Light. It seemed only right that this “Architecture as Event” and these ephemeral spatial entities, would be designed by a technique like light painting which essentialy researches the concepts of still-time and performance and brings them together under the use of Light. Light is able to manifest and re-animate these fleeting moments, even after they are long gone, and re-create a spatial experience where no forms are constraining, a performative action, an event and, finally, an architecture that now only exists in a still Light Painting or a Video Performance.


page. 53


page. 54

0:03

0:06

0:09

0:12

0:15

0:18

0:21

0:24

0:27


page. 55


page. 56

0:04

0:08

0:12

0:16

0:20

0:24

0:28

0:32

0:36


page. 57


0:03

0:06

0:09

0:12

0:15

0:18

0:21

0:24

0:27

page. 58


page. 59


page. 60

0:04

0:08

0:12

0:16

0:20

0:24

0:28

0:32

0:36


page. 61


page. 62

0:05

0:10

0:15

0:20

0:25

0:30

0:35

0:40

0:45


page. 63


0:03

0:06

0:09

0:12

0:15

0:18

0:21

0:24

0:27

page. 64


page. 65


page. 66

0:05

0:10

0:15

0:20

0:25

0:30

0:35

0:40

0:45


page. 67


page. 68

0:04

0:08

0:12

0:16

0:20

0:24

0:28

0:32

0:36


page. 69


page. 70

0:04

0:08

0:12

0:16

0:20

0:24

0:28

0:32

0:36


page. 71


page. 72

0:04

0:08

0:12

0:16

0:20

0:24

0:28

0:32

0:36


page. 73


page. 74


page. 75


page. 76


page. 77


MArch GAD Portfolio Karolos Keranis