top-cat Posted September 4, 2014 Share Posted September 4, 2014 If you want UV as an effect, get some UV units seperately. I've said it before and I'll say it again. UV in LED terms is not UV at all. It is literally not ultra violet light and nothing to do with the black light lamps you get in UV cannons. UV in LED terms should be taken to mean Congo blue. Link to comment Share on other sites More sharing options...
musht Posted September 4, 2014 Share Posted September 4, 2014 UV in LED terms is not UV at all. True Black Light, UVA, LED units are rare , struggling to think of a Euro one, but here`s a U.S. one http://www.bhphotovideo.com/c/product/809876-REG/Altman_SS_UV30_BK_Spectra_UV_30_LED.html Price is main reason dont see so many >390nm LED units around. For UV emiting lights for OP, would always go fluro over mercury discharge `cannons` Link to comment Share on other sites More sharing options...
swampman Posted September 8, 2014 Share Posted September 8, 2014 The congo "dark" blue issue lead to double incandescent wattage on RGB cyclorama battens to get a balanced white AND a deep night blue (incandescent: more red, amber & heat produced) . Top-cat thanks for good explanation of the (horrible) limits of Royal, police car or dentist LED blue without digging into ETC literature... Now when do the RGBCbAW+UV units widely arrive on the market avoiding some technological limitation i.e. patent issues? Link to comment Share on other sites More sharing options...
paulears Posted September 8, 2014 Share Posted September 8, 2014 The price seems pretty good to me. I think what I would want is one as a sample, so that I could assess it. I usually buy two - as they're far more useful in pairs, even if they turn out to be something I then don't buy more of. I'd have to agree with TC re: the UV, as lots I see seem either the deep blue or even cyan - and they're pretty useless for traditional black light requirements. If you get the pair, and they're ok, even perhaps ignoring the UV, then that price sounds worth a go - plus you have a couple extra, without the case to use as spares if need be. If you find they have great performance, but less solid construction, is this a problem? I've been quite happy with the longevity of the kit I buy. I know that if I do certain things, the cases will crack, and I know which screws are too soft to remove with the wrong screwdriver. I would NOT hire these out to strangers but I'm not intending to. Is the construction good enough for what you want to do? I'm very positive about my lighting and audio purchases from China, and I've had a good experience of ealing with them. Link to comment Share on other sites More sharing options...
musht Posted September 8, 2014 Share Posted September 8, 2014 Seven colours of Selador are Red, Orange Red, Amber, Green, Cyan, Blue and as they prefer to call it Indigo. White is in a way a kludge ,an effective one,but won`t give you a deeper red or blue. http://www.sciencelearn.org.nz/var/sciencelearn/storage/images/contexts/light-and-sight/sci-media/images/the-visible-spectrum/657631-1-eng-NZ/The-visible-spectrum.jpg Link to comment Share on other sites More sharing options...
Don Allen Posted September 8, 2014 Share Posted September 8, 2014 As an example, if you look at page 5 of the Luxeon Rebel Color Datasheet a blue emitter has a typical wavelength of 470 nm and a typical spectral half width of 20nm so you would assume that it is going to be extremely difficult for a led manufacturer to be able to reproduce the range of blues we are used to using in theatre lighting when using a tungsten light source and a colour gel, However if you look at the spectral chart of Lee 195 Zenith Blue as an example of a deep saturated blue, as well as the main wavelength of 46% of blue 450nm, there is a strong component 40% of red 700nm, 15% of violet 400nm, 25% of indigo 425nm, 5% of orange 665nm. (I know it adds up to more than 100%, please accept this as a concept, not a hard fact.) So by adding more different colour led emitters in a led fixture and using a control system such as light factory with advanced colour heuristics or a desk with similar properties (forget the term) so when we ask for a particular gel colour, the program adds whatever colours are available to make up the colour spectrum, we can fool the eye into thinking it is getting a close rendition of that colour. Link to comment Share on other sites More sharing options...
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