Light: magnetic navigation, cyanotypes, VR and blue light.

I have recently been experimenting with mediating light using the Cyanotype contact print making in which UV light is filtered through objects and ohp Film to produce ‘Prussian blue’ images. 

The collection of photograms entitled ‘Panvirus” will be completed shortly. I have a few very large pieces to complete which should include 4 large screens (2m x 1m), 1 maybe 2 large square pieces (fertile crescent) and an installation (a photogrammed table set for dinner on cloth) entitled war table. 

While making this work, I have been asking the question ‘ How does this work relate to my VR Practice ?I considered how I use light in VR and then began to ask in what way does lighting aid player navigation in virtual reality (VR) and also potentially open world navigation ? ’ 

This is an extension of the research I conducted 2018-2020 when first using the unity game engine to produce virtual worlds. I became interested in wayfinding and navigation in real world and virtual settings. I experimented with game engine lighting and other visual methods used to imply affordances to the ‘player’ so as to indicate access routes and pathways, considered landmarks, mental modelling and other world navigation tools. 

I am beginning to bring together these two processes, Light in Cyanotype print/photogram making and Virtual Reality (VR) Navigation. I am doing this by examining bird migration. I first began thinking about migrating birds when I produced a work entitled ‘Nightingale’ for my cousin Rebecca. She has an exceptional musical ability and I wanted to create an illustration of the beautiful whistle she makes as I’ve never heard anyone else be able to produce this beautiful sound.  One day I happened to meet a fledgling nightingale on my garden path and the concept for the work slowly emerged from this. 

I began considering where does the nightingale go in the winter time, how does it migrate ? Now, this is where things got really interesting… 

I discovered that birds have a magnetic sensory in between their eyes by which they can sense the earths global magnetic force. I researched this further in Nature research papers. It is understood that this only functions in the presence of blue light. It is through the use of this internal mechanism that birds can navigate vast spans of ocean without seeing any landmarks. Other insects and animals seem to have this ability to a greater of lesser degree. 

This led to asking if humans have the same sensitivity to magnetic force. I found research, conducted over 10 years (2000 – 2010) in which the results concluded that humans did indeed have this function however the results could not be replicated by other researcher in the field. This meant that it could not be verified, the enquiry faded into oblivion and the original researcher basically said ‘ bugger you’.. and walked away (we can all sympathise here!) However, in 2016 researchers built a box which excluded interference from general magnetic fields in which starved male human test subject were shown plates of food on screen. The test subjects blind folded, and whilst on a rotating chair, they were asked to point to the place where the food had been… the test concluded that there is a high probability that humans do indeed have magnetic perception and can use this as an internal compass to locate food. 

This is interesting because the modern world of advanced technology is built on magnetic sensors. In every phone & mobile device magnets help to pinpoint its location on the surface of the planet. The planet itself is in fact one enormous magnet. Essentially, magnetosensory perception only works in the presence of blue light . This blue light is produced in the chemical reaction where an iron ion is lost in the process, during cyanotype print making.  

Also, there is increasing concern that bird migration can be disrupted by land lighting over cities and on coastlines. Bird migration can be affected by changing environmental conditions such as unusually large storms/cyclones insect availability etc and as such, is being observed in relation to climate change. Birds are also it seems, essential for seed dispersal which is another essential factor of bio diversification, wild birds literally rewild nature. 

So, out of this process I would like to produce a small set of bird illustrations, I say that they will be illustrations as my thinking is that each image will tell a fragment from a story. It would be interesting to present these in the spirit of ‘Ergodic’ literature in which there is no linearity to the story itself as the observer can place these fragments together to form their own stories. The illustration may be animated or at least form the basis of animation within a ‘game’ story structure. It is likely this developed will be documented on my commercial blog and portfolio at some point.

I also intend to explore light further in VR as a continuation of my own independent research in virtual reality. This activity will follow on from the Cyanotype photograms produced for Panvirus. I hope to include aspects of light, shadows and effects will be introduced in the Panvirus virtual gallery which has already been set up in Unity Engine to produce a 360 image and very basic app prototype (which will also be posted to my commercial blog and portfolio in the near future). 

Next : 


‘Fertile Crescent” 60cm x 60cm Cyanotype photogram. 

‘Consumption’ Cyanotype screen 

‘Suspension’ Cyanotype screen 

‘Reconnection’ Cyanotype screen 

‘War Table’ installation – welland valley. 


Panvirus 360 image (self-directed)

Panvirus VR prototype(self-directed)

‘Automatic Writing’ book cover (self-directed) 

‘And they followed the moon to find home’ cynanotype print/photogram illustration (self-directed) 

Continue light experiments and magnetic sensory navigation research. 

Coronavirus Cyanotype Process

Collected Wild Flowers which are sometimes pressed and sometimes not.
Pan Virus (Print arrangement) 
Re-used packaging plastic
Pressed Natural Flora – Calendula & Forget-me-nots 
Soap Bubbles
Stone Heart
Lime Juice 
On Cyanotype treated Paper

Pan Virus (2021)


These are the spaces in which I explore, conceive, experiment, grow and create. 

Merribel Woods ( SSSI )

Digital Editing, Design & Production Set Up

Adobe Creative Cloud  / Blender / Unity Engine/ Unreal Engine / oculus / iOS / windows

100% Sustainable Energy (Electric & Gas) OVO 


Composition Area 

Veg plots with wild flowers.. 

Local Delivery : My trusty old bike

National Delivery : WEGO Nottingham

Burglar Alarm 


Note: Can easily be bypassed with dog treats…. 


The Cyanotype print/photogram process was originally invented in Birmingham by John Frederick William Herschel (1792-1871) as a cameraless photographic technique. This was subsequently used to produce the first illustrated book of botanical prints produced by Anna Atkins (1799 – 1871). The book was called British Algae: Cyanotype Impressions. 

My father remembers going to the blueprint shop early on in his working life as an engineer in the car factory, and asking for a blue print. This was then produced using the original Cyanotype formula. He remembers that the print room always smelt of ammonia. 

After mixing the solutions myself, I painted the surface of simple print paper. The paper was poor, disintegrated in the washing process and the blue tone was very light.  I continued to experiment with the process, producing both dry and wet cyanotypes. 

I documented this experimentation in my sketchbook, working through a variety of mediums, natural forms and found objects as well as using my body to cast shadows, noting the intensity, direction and time of the exposures. 

Paper Experiments 

Plant forms 

Locust Copyright Sarra Hornby All Rights Reserved 

OHP Film : Photographic Negative (My own Photography)

OHP Film : Drawn Illustration 

Painted Glass

Pinhole: Spectrum Circuit Board 

From Hex Experiments. 

Masks : Paper Translucency (OHP Film)

Masks : Objects 

Solutions : Bleach, Household washing soda, lime juice, Sea Salt, sprayed water




Sewn Electronics 

Cyanotype Plague mask (in construction) 

360 Gallery (in development – Unity Engine) 

iOS App

VR world (in prototype white box model – Unity Engine ) 

open world (in development – Unreal Engine) 

Windows PC 

Reflection : Nature / colour / Light

During the last year and a half I have had to be adaptable, flexible and resilient.. as we all have. I have shifted direction a few times to adapt to daily change while applying my practical skillset to help out in the pandemic where I could. During that time, much of what I have seen and read has been internalised. 

While dealing with the immediate crisis, in the back of my mind, I was aware that a larger crises loomed on the horizon… that of human extinction through the runaway feedback state of various ecological systems ( aka global climate crises).

So, feeling compelled to make art about my experience of the pandemic, make sense of the science and broadcast news I set about dealing with this growing internal tension, 

I felt a need to bring more colour into my still images and I was also drawn to a key aspect of my work, that of light. For me, light is uncertain, shifting changing and which, through the progress of the sun, marks time and giving  a sense of self in space and time as it filters through the bodies senses. Light in both nature and the computer can be mediated as if it were a material. 

For me, light represents the uncertain, shifting relationship between humanity and nature while embracing the evolution of advanced technology (in all its positive forms and with all its potential to help us in our hour of need… even if sadly coming out of times of hostility). 

A few pieces from my personal experimental practice that considered colour and light pointed to a potential solution. 

One (2008)

Kinetic Sculpture 

Paper (Western) with Magenta andCyan dyed Thread, gold thread. 

Interconnection Screen (2008)

Paper (Western) Kinetic Screen sewn with magenta dyed cotton thread.

Interconnection Projected Video (2008)

Film projected on to Paper (Western) Kinetic Screen 

Time (2008) 

Kinetic Paper Screen 

Image captured from Film produced on Kings Hill, Uppingham. 

Guardian : The carcass cleaner (2007)

Paper (Western) with Magenta, Cyan and Yellow Dyed Cotton Thread, 


Two Paths : Heisenberg’s two slits experiment (Quantum Mechanics) 20013

Digital Photograph

Natural Light digitally photographed through slits in paper cut in the form of paths which were drawn on the landscape from walkers in the Pennines. 


Digital Screen Capture 

Unity Game Engine environment modelling Lighting experiments (wayfinding in digital environments) 

Helix (VR) 

Digital Screen Captures

Unity Game Engine environment lighting (Optimised for Oculus Quest) 

I remembered the Body Electric Len Lye exhibition at the Ikon, Birmingham which I spent many hours in a few years ago and, in addition to sketching and recording the movement of the kinetic sculptures, I remembered his really interesting set of photogram. This would be a way of capturing natural light (photons) and shadows formed from ‘real’ objects and materials. 

I didn’t want to handle high toxic chemicals but became interested in how phtographs can be made at home. My research led to the Cyanotype process which I will explore further in subsequent posts.