Dear Anne,
A standard ganzfeld illuminated by Quartz Iodide globes is what you
need. You can make it yourself. Buy two perspex hemisheres ($40.00 each
for 7.5mm thick 40cm diameter ones here) and used a blow torch to solder
them together and cut a viewing hole and ports for the QI light sources.
Fill the groove where the hemisheres join with no more gaps or silastic.
Paint inside with standard dulux flat white. I converted to standard
illuminant magnesium oxide paint which is hard to get, water based and
uncleanable, with absolutely no measureable improvement in measured
intensity or any noticeable effect on my normal vlues or change in the
subjective appearance (except the surface was now less smooth). The QI
lights run at 24 V max, now come with their own power supplies and can
be controlled by standard pots as in household light dimmers. Two QIs
mounted above and behind the head in a 40cm bowl give 600cd/M2 which is
too much for my purposes (electrophysiology). Smaller bowls are brigher
but you cant mount so many QIs. You only need check on how you drive the
controlling resistor with a computer and claibrate intensity to the
input of the resistor (non linear almost log)
-- yrstrulyvaegan +-------------------------------+ Mobile & Dir: +61 0404 468 100 | Vaegan | Work Message: +61 2 9231-1833 | Manager Visiontest Australia | Work FAX: +61 2 9232-3086 | 1st Floor, | Email : vaegan@unsw.edu.au | 187 Macquarie St, | __o o__ | Sydney, NSW, 2000 | _ \<._ _.>/ _ | AUSTRALIA. | (_)/ (_) (_) \(_) Bye! +-------------------------------+ NIL ILLEGITIMUS CARBORUNDUM This Signature reads more clearly with a fixed width text such as courier.Please support ISCEV and submit a paper to 'Animal Models In Clinical Electrophysiology of Vision' A Special Issue of Documenta Opthalmologica. I am the guest editor. The Deadline is the end August. You can link to the Doc Ophthalmologic guidelines directly at http://www.wkap.nl/journalhome.htm/0012-4486 or through the links button on the iscev web page http://www.ukl.uni-freiburg.de/aug/iscev/iscev.html
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