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View Full Version : Is this another ebay con?

ProgressiveScan
01-01-2002, 10:00
http://cgi.ebay.co.uk/aw-cgi/eBayISAPI.dll?ViewItem&item=1316427703

If not, are there any websites where I can get hold of the info?
MikeToone
01-01-2002, 10:11
I have seen TV Sceen magnifiers, but never seen anything as big as this.

Then again the Seller does have 85 positive ratings, so it does make you wonder.
rwniel
01-01-2002, 11:35
The ones in these plans appear to use a 3 x magnification "Fresnel" Lens. I found these details from another site:-

Distance from Screen / Wall Image Size - Quality

4 to 5 feet / 50 to 60 inches - Excellent

5 to 6 feet / 60 to 80 inches - Excellent

6 to 7 feet / 80 to 100 inches - Very Good

7+ feet / 100+ inches - Good

I would assume the further the image from the screen itself, the less projected light and hence the greater reduction in brightness/contrast. Has anyone here built one? Is it basically the case of plonking a lens in front of the tv? - highly technical description. :)

Update: Here is someone who built something similar (http://ourworld.compuserve.com/homepages/John_Reder/fresnel.htm) - the one on ebay appears to focus the light onto the wall though, rather than having it "floating" in front of the tv.
hookbeak
01-01-2002, 12:39
out of interest i might have a go on my pc monitor - anyone know where to buy a decent sized fresnel lens online ?
Bapapapa
01-01-2002, 13:31
Just smear vaseline on your screen and sit very close for the same effect.
arb
01-01-2002, 18:40
stay well clear of fresnel lenses - i bought one from lectropacks for my 28" ws telly as i was curious too ( magnifies up to 40") - for a start they a tinged blue ( due to the concentric rings) and therefore everything you watch has a blueish colour to it -and at the end of the day it looks really naff protruding 6"-8" in front of your tv - i manged to sell mine on for the same price i bought it for - phew! - lesson learned :)
gram99
02-01-2002, 10:28
Originally posted by Bapapapa
Just smear vaseline on your screen and sit very close for the same effect.

If you have any left that is :nuts: Appria where are you!
rwniel
05-01-2002, 02:53
ProgressiveScan: Here is a bit more information (http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=0038A5).