Archive for May, 2010

24 HOURS OF REAL WORLD ILLUMINATION

May 22, 2010

By the time I got home early on Thursday morning I had not slept in 41 hours. By then I was in a sort of dreamlike state, going over the events of the previous day in my head, hoping I had collected enough data for my project and wondering if the experience had been worth while. All in all the experience itself was extremely interesting, particularly the time between 4:30-6:00 a.m when I was the only person in the junction. Then to see how busy it became during the afternoon made me realise how relevant it was to use the phrase ‘it’s like Piccadilly Circus’, which is commonly used in the UK to refer to a place or situation which is extremely busy with people. I was asked at one point by a curious man whether I worked for Google Earth, at least it’s good to know my actions appeared genuinely professional.

Looking over the photographs I’ve noticed a couple of variables that I should consider if the results are to remain consistent. The first is a slight unbalancing of the camera during each exposure which if ignored will create a blurred and jittered HDRI which is not what I want. Also I was very conscious of the sphere getting dirty over the 24 hours with me constantly moving it around. The results of the last few hours are a little murky, however this wasn’t as bad as I had predicted and shouldn’t affect the illumination of my scene in 3D.

I’m using a program called Photomatix to convert the images into HDRI (also referred to as radiance maps). I had intended to do this in Photoshop but there is no function that allows me to ‘unwrap’ the mirrorball into a flat 360 degree panoramic image. After photographing the sphere from the side closest to the neon signs I did the same for the other side, facing the memorial. I thought this would allow for a fairly decent 360 degree view of Piccadilly Circus when both sides were unwrapped and stitched together. However, with the final HDRI next to each other the stitching process became a little tricky as both images became warped and felt out of place when aligned. Ultimately I was pretty happy with how both the images had unwrapped from the mirrorball in Photomatixs. The ‘pinching’ of the corners wasn’t as severe as I expected, leading me to the conclusion that I only need to use the images from one side, and not both. In the end I have decided to use the side closet to the neon screens as this plays such an important role in the illumination of my scene during the night time.

I positioned the camera exactly 1 meter from the sphere, photographing exposures of 1s, 1/8, 1/250, 1/2000 and 1/4000. After that I used the Digital Lux Meter to record the surrounding environmental illumination. My results can be seen in the table below.

LUMINANCE VALUES IN PICCADILLY CIRCUS DURING THE 24 HOURS OF WEDNESDAY 19TH MAY 2010

TIME – LUX
00:00 – 25-50
01:00 – 25-50
02:00 – 25-50
03:00 – 25-50
04:00 – 25-50
05:00 – 180
06:00 – 4000
07:00 – 19000
08:00 – 44000
09:00 – 58000
10:00 – 68000
11:00 – 86000
12:00 – 97000
13:00 – 118000
14:00 – 19000
15:00 – 12000
16:00 – 9600
17:00 – 7600
18:00 – 10300
19:00 – 4000
20:00 – 3000
21:00 – 180
22:00 – 25-50
23:00 – 25-50
24:00 – 25-50

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PICCADILLY CIRCUS / THE PHOTOPERIOD EFFECT

May 16, 2010

Not long after the Bunker exhibition I started to feel increasingly drawn towards the conceptual relevance of using site specific Image Based Lighting within a virtual environment. For the majority of this degree I have researched, questioned and utilized such a technique to incorporate perceptually real synthetic objects into live-action scenes. I think it’s important for me to reiterate how my project has maintained this consistent method of practice that at the core has been responsible for examining hyper-real computer generate images. As a point of departure these notions of simulating realism have questioned the relationship between a real physical space and the virtual world.

As a result I have slightly altered the nature of my final film taking into consideration the importance of exploring artificially illuminated real world places. Following my interest in photobiology I’ve been observing how the human circadian system is entrained to a 24-hour light-dark pattern that mimics the earth’s natural light/dark pattern. We are constantly surrounded by environments that disrupt this pattern, particularly in urban spaces where the bright lights of the city never sleep. I began thinking of certain places in London which never completely fall to the darkness of night, whose surroundings are artificially lit 24/7. Lux is the SI unit of illuminance and is used in photometry as a measure of the intensity of light as perceived by the human eye. Using this calculation I hope to investigate the difference in environmental illumination over the course of a day.

SAMPLING THE LUX VALUE IN PICCADILLY CIRCUS

The idea is to spend 24 consecutive hours in Piccadilly Circus where I intend to record every hour the surrounding environmental light. Firstly this will be calculated using a Digital Lux Meter which should give me an accurate reading of the light intensity, noting this down I am interested to see how this changes throughout the night and day. Secondly, a panoramic photograph will be taken every hour of the busy junction that will later be converted into 24 separate High Dynamic Range Images. By sampling the illumination and lighting data of Piccadilly Circus over a full day I intend to examine the changes in quality and intensity of light from the sky as well as the emitting neon signs.

My intention is to document and redefine elements of Piccadilly Circus through photographic texture mapping, creating an abstract representation of the space in Maya. The 24 HDRI’s will be used sequentially to illuminate the scene replaying the entire day over a 2 minute animation. As the intensity and quality of light changes from night to day a dynamic particle simulation will respond and visualize the results collected by the Digital Lux Meter.

LIGHTS OUT / IS IT OVER

May 10, 2010

Is It Over opened last Thursday to a buoyant response from the public. Although the space was still rather damp, everyone’s work felt thoroughly physical, bold and highly considered.

The exhibition allowed me to develop a site specific piece of work that dealt with lighting as creative process. Lights Out attempts to simulate a photoreceptive response within an dark confined space devoid of any natural light. Standing directly on top of the bunker I captured the surrounding environment light by photographing a chrome sphere at multiple exposures, compressing them into a single high dynamic range image (HDRI) in Photoshop. Inside the bunker I photographed some of the surrounding walls and floor, documenting the physical space. Then in Maya I began modeling a virtual bunker space using these photographic concrete textures and brought in the HDRI to illuminate the scene, creating organic structures that simulated a growth response from the floor to the ceiling. These ‘shoots’ are surrounded by square shaped leaves that reiterate the shape and physical restrictions of the bunker to natural growth. Ultimately the work succeeded in the process of taking natural light from the outside inside to drive a photoreceptive set of motions.

The title Lights Out refers to the WW2 air raids when the British people were told to turn off electrical lights so as to avoid being seen by overflying aircraft.