You should find that many of these lamps will have a little known value written on the side of the box that will help you decide. The ]Colour Rendering Index (CRI) of these lamps will tell you how faithfully they will reproduce all colours of the spectrum. If you find a lamp without this information on the side of the box, then be careful and perhaps don't buy it.
A CRI of greater than 90% (0.9) with a colour temp between 3000-4000 will be adequate for the shack and reading of resistors and colour codes. It turns out that brown and deep reds are very difficult colour to faithfully reproduce from blue rich white light, which isn't a new phenomenon since long arc fluorescent, CFL and LED all derive white light the same way. For reference low pressure and high pressure metal halides have a CRI of 100% which is why you find them used in art museums, ditto tungsten et al. However pay careful attention to noise from these more modern lamps, the EMI from some cheap and nasty LED/CFL lamps is just hideous. We all want to preserve the noise floor for our Elecraft RX's, just to keep this on topic. 73 Matthew VK5ZM On 28 September 2015 at 04:21, Dale Putnam <[email protected]> wrote: > For those looking at CFLs or LEDs in the shack, and presuming that is > where you built, very close attention must be given to > the color and intensity of the light emitter. Especially if you are > working with hole through color coded components, like resistors. > The perceived color of the bands/dots may NOT be exactly what was > intended, NOR what will be percieved when re-examined under direct > sunlight. Direct sunlight is tuff to come by after sundown and prior to > dawn, and with the longer hours of winter darkness coming, look hard and > long at the different light emitters. > > a simple word to the builder, from the... now a bit wiser. > > Have a great day, > > > --... ...-- > Dale - WC7S in Wy > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
