1. What about the light beam from an entrance. 2. Which time? If the entrance faces West or East???
Just search on lux meters and you will get a lot of hits. This place has a kit one for under $60 - www.electronickits.com/index.htm They even have a tube amplifier kit! Just what you need for your record player and reel to reel tape player. Personally, I would go with a laser turntable, www.elpj.com, and you might even get some change from your 10 to 14 grand. Nigel You wrote on: Wed, 2 Jul 2008 14:38:44 -0500 From: David e-mail: [email protected] > Shouldn't your cave map note the normal threshold boundary > of total darkness? > > Here is an e-mail I received from a company that sells a gadget > that could measure light intensity in a cave passage and possibly > determine the boundary line of total darkness in a cave: > > _____________________________________________________________ > > Our system will provide you with accurate measurements of the light intensity, > or lack of it. > > The range is 0.001 ft candles to 140 ft candles. The device is a handheld > portable meter with a sensor connected with a cable. The meter has a > backlit screen, so when taking readings you will have to make sure this > is turned off, otherwise it will have an impact on your readings. > > This sensor is only measuring light, which is the visible part of the > spectrum. It will not record any UV or IR radiation. > If this is what you are looking for, the meter and sensor will cost > $1,385.00, FOB Glenside, PA. > > > Best regards, > > Terry Harding > Director of Sales & Marketing > North America > > > Solar Light Company, Inc. > 100 East Glenside Avenue > Glenside, PA 19038 > (215) 517-8700 > (215) 517-8747 fax > > www.solarlight.com > ___________________________________________________ --------------------------------------------------------------------- Visit our website: http://texascavers.com To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
