Digital BW, The Print

I apologize if this has already been discussed, but I remeber 
hearing a professional printer say that when he has an exhibition he 
supplies one 4700K bulb per print as this is the light he uses when 
doing in his studio while printing and wiewing. (He always expects 
his bulbs to be returned after a show). How this would be 
accomplished with LED lighting is a question I will leave to the 
experts.

Warm Wishes for a Healthy and Prosperous 2009!

Rudy
So.Hadley, Masstts
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--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "dlruckus" 
<dlruckus@...> wrote:
>
> I can't speak for hi output very broad spectrum led lighting but I 
can
> say a bit for generic LEDs.
> I have an ongoing project of a diy XYspectro utilizing LEDs(silly I
> know but interesting and educational). In any event, in the course 
of
> designing this, I've had reason to measure and evaluate a fair 
number
> of off the shelf LEDs. In general I found that it would be very
> difficult to come up with a set that could be reasonably 
considered to
> approximate any normal lighting's full spectral curve. I was able 
to
> construct full spectrum coverage(roughly 340-750nm) but it has a 
lot
> of spikes in output. That isn't a major issue for my use as it can 
be
> accounted for in calculations but I suspect(as you have mentioned
> Ernst) that it would be very expensive to individually control 
gangs
> of relatively narrow peak LEDs in a manner that emulates something
> like a continuous spectrum incandescent for large scale viewing
> purposes. It took 13 LED bands for me to be comfortable with what I
> considered adequate output for reasonable precision of results. 
> 
> Regards,
> Duane
> 
> 
> 
> 
> 
> --- In DigitalBlackandWhiteThePrint@yahoogroups.com, Ernst Dinkla
> <edinkla@> wrote:
> >
> > pr_roark wrote:
> 
> > > I think the LEDs are clearly the future, but I'm not sure what 
the 
> > > light quality (CRI) is or whether there are appropriate 
sizes/lumens 
> > > for our replacement project.  Actually, there is a program in 
> > > California that is going to end up giving our gallery free 
lights.  
> > > So we have to pick from what they have, which seems to be 
simply a 
> > > selection of CF floods and 'spots' (more like floods than a 
halogen 
> > > spot).
> > > 
> > > I, too, would like to hear if anyone has experience with the 
LEDs.
> > > 
> > > Paul
> > > www.PaulRoark.com 
> > > 
> > > 
> > 
> > Paul,
> > 
> > Video and camcorder users need small floods and spots with 
> > continuous output. It looks like they embrace LED lighting 
> > faster, armatures that have all LED types included like Red, 
> > Green, Blue, Amber, White, etc to get more full spectrum. I 
> > have not seen a spectral curve yet nor a decent CRI quote 
> > for them. I suspect still an (expensive) compromise on color 
> > quality.
> > 
> > http://www.s131567196.onlinehome.us/
> > 
> > http://www.elementlabs.com/KelvinTILE.html
> > 
> > -- 
> > Met vriendelijke groeten, Ernst
> > 
> > 
> > |  Dinkla Grafische Techniek  |
> > |     www.pigment-print.com    |
> > |             ( unvollendet )            |
> >
>