Track lighting suggestions?

[Darin Boville]

I'm struggling with track lighting. I want to buy about 40-50 linear feet of track and two dozen track heads using LED bulbs for a gallery0style environment. Want to keep it on the inexpensive side.

But I'm bewildered by all the different bulb types.

In LED, what's my best move as far as bulb type? (That will determine my fixture type, too, of course.)

What degree of spread would be right for a gallery environment, lights about 10-12 feet up, installed at any angle I desire (i.e. tracks not installed yet).

Thoughts on color temperature of the bulbs?

--Darin

[gleaf]

Issue with LED bulbs is heat sink ventilation. I will do some research in the morning. Many need clear airspace around them.

[Amedeus]

There are many factors playing here. LED lighting is getting better all the time.

I've settled on PAR38 spot lighting, warm for lighting up individual prints/frames up to 16x20 ... for my larger pieces I'm using PAR38 flood, soft white warm. My throw is few feet shorter than yours.

No issues with cooling.

YMMV.

[polyglot]

If you're keen on LED, you need to worry about colour quality (the uniformity of the spectrum, i.e. how close it is to blackbody with no big spikes or holes in the spectrum) as well as colour temp. Make sure the CRI of the bulbs is over 90 otherwise things can look wrong.

Classic tungsten gallery lighting is 3600K and that will work well if the gallery as a whole is lit at those sorts of temps. You could also use about 5200K (sunlight) but that requires that you don't use tungsten lighting elsewhere, or the prints will look like they're in blue highlights.

In selecting bulbs, I would buy a couple of individual fixtures and test out a handful of different bulb brands with a few different print technologies (B&W, RA4, inkjet and maybe ilfochrome if you can get it). Different print technologies have different ink spectral responses, so while one kind of print might look OK under a bulb with poor CRI, a different kind of print might look quite inaccurate due to different dye selections.

[Amedeus]

I second polyglot on the CRI ... higher is better and preferably over 90 since that is where the reputable, more expensive brands are. Some of these LED lamps put out less light compare to the lower CRI lamps ... so look for the compromise.

[Darin Boville]

I second polyglot on the CRI ... higher is better and preferably over 90 since that is where the reputable, more expensive brands are. Some of these LED lamps put out less light compare to the lower CRI lamps ... so look for the compromise.

And brand recommendations (or better, links?). I know the quality of lighting is important but I'm also very conscious of price.

--Darin

[Darin Boville]

Make sure the CRI of the bulbs is over 90 otherwise things can look wrong.

Can I trust the CRI of the no-name brands? The big names are sooo much more expensive...

--Darin

[Amedeus]

No, you can not in my experience ... I do lighting development for a living and can measure all parameters around light bulbs. There's a difference and you pay for it.

No different than buying fluorescent tubes ... KinoFlo over residential tubes ... way different in performance ...

YMMV ... what is not good enough for one, is perfect for the other.

Can I trust the CRI of the no-name brands? The big names are sooo much more expensive...

--Darin

[Darin Boville]

No, you can not in my experience ... I do lighting development for a living and can measure all parameters around light bulbs. There's a difference and you pay for it.

No different than buying fluorescent tubes ... KinoFlo over residential tubes ... way different in performance ...

YMMV ... what is not good enough for one, is perfect for the other.

What brands should I look at that are not quite good enough for a pro like you but probably not absolute junk? I see a big difference in LED prices....

--Darin

[Nathan Potter]

The differences in LED lighting prices result from the CRI values and the efficiency of the heat sinking. The CRI value derives from the particular mix of RGB emitters that are used. To best match a true black body radiator requires a lot of work optimizing the mix of RGB diodes at the factory. The best now can achieve a CRI of 100 (a near perfect match). From what I've seen a CRI of 90 is adequate for the faithful viewing of color prints and is nearly irrelevant for black and white prints. But ultimately the CRI one uses depends on how fussy you are.

Heat sinking costs money and bulk around the bulb but is essential for long life.

I've always thought there should be a disclaimer in galleries about the lighting, stating what the gallery lighting is and that prints, especially color, will look much different in home lighting if the spectral output at the home is materially different than that in the gallery.

There is a wealth of stuff on the web about CRI values and heat sinking. The best advice is to pick up some likely candidates and try them out, particularly to evaluate the angle of spread. The historic intensity at the print for critical viewing is at least 100 FC but some galleries can and do vary this for print preservation purposes.

Nate Potter, Austin TX.