LED light bulb for Painting on sale

[Jay]

I just went by a big box DIY store and found they have LED light bulbs on sale ($20).

These bulbs work in existing lamps, don't require a warm up time, last a very long time, and are very efficient so they don't put out a lot of heat. The light is more white than the CFL and incandescent bulbs we used to use though. If you need details email or pm me and I'll send it to you. I don't want to spam the forum.

[WizardOne]

Home Depot? Menard's? FleetFarm? Lowes?

 

How many Lumens does $20 bucks get you? and about how many individual LEDs are arrayed together in this thing? (I think it's OK to review a product and say where you got it. People do that about paintbrushes, glues, and paint on these forums.)

[Jay]

Home Depot? Menard's? FleetFarm? Lowes?

 

How many Lumens does $20 bucks get you? and about how many individual LEDs are arrayed together in this thing? (I think it's OK to review a product and say where you got it. People do that about paintbrushes, glues, and paint on these forums.)

 

Home Despot.

Ecosmart brand

9 Watt power draw = 420 lumens = 40w regular bulb

3000 degrees K spectrum

It has a glass diffuser that makes it look like an incandescent so I can't tell how many LED's it has in it.

Rated life is 50,000 hours.

Runs much cooler to the touch than my CFL bulb does.

[morganm]

That's pretty weak for $20.

 

I use full spectrum CFLs that put out 1,300 lumen for less than $20. They are n:vision ESM27 27 watt 5500k (100 watt daylight or full spectrum I think the package said) Usually have 4 of them mounted in different positions. I get these at Home Depot and other big box stores.

[Hot Lead]

That's pretty weak for $20.

 

I use full spectrum CFLs that put out 1,300 lumen for less than $20. They are n:vision ESM27 27 watt 5500k (100 watt daylight or full spectrum I think the package said) Usually have 4 of them mounted in different positions. I get these at Home Depot and other big box stores.

 

Just a few things to consider when lighting your work area.

 

Color Spectrum:

 

Don't forget CFLs, even "daylight" ones, have a different spectrum output than incandescent bulbs. They tend to run "bluer" and have some pronounced spikes in the light wavelengths they output.

 

This site shows the spectrum for many CFLs, including an n:vision (about midway down the page):

CFL Spectrums

 

 

Compare that to the spectrum of full sunlight on this analysis page:

 

And "warm" LEDs here:

 

 

The fluorescent has a less complete spectrum and is very spikey in the orange, green and blue wavelengths. LEDs are spikey in blue, though with this warm one the manufacturer managed to minimize that. Overall the LEDs have a broader fill of the spectrum compared to CFLs, but I agree the technology vs. cost effectiveness isn't there yet.

 

I just wanted to point out that "sunlight" CFLs are not perfect either.

C.R.I.

 

Companies are using color temperature as a marketing touchstone, but really you can see that natural sunlight tops out in the 3500K range, not 5500K. Color rendering index (C.R.I.) is more important - this is an industry term for how close the light emitted comes to pure sunlight. The scale is 1-100, with 100 being natural sunlight. C.R.I.s in the mid to high 90's are closest to sunlight. Ott Lites, for example, have 90-93 C.R.I. Always look for the C.R.I. listing on the bulb! If they're shy about listing it, chances are it's not "full spectrum" enough...

 

 

Personally I run two 100wt equivalent "full spectrum" Feit CFL bulbs from the sides for fill light, but use a 35wt 4100K 98CRI Solux halogen bulb for the main middle light. This lets me see the mini in a close approximation to sunlight, while relieving eyestrain with the side lights.

 

Solux is NOT cheap ($15 a bulb), but I got a Solux lamp off eBay for a steal. Since it is incandescent (and will burn out) I only use it for painting, turning it off for assembly, prepping, etc. I've compared it to my wife's Ott Lite and the Feit "full spectrum" CFLs. The difference is less pronounced with the Ott Lite (though noticeable), but very obvious with the CFL's - they are much bluer.

 

Finally, both CFLs and Halogens emit UV light, which can damage the retinas and fade colors overtime. This isn't as important for short-term mini painting unless you're spending hours a day under the lamps. It can have detrimental effects when used as long-term display lighting, though. My Solux has a UV filter built in. It's not a bad idea to pick up some UV filters for CFL lights if you use them. You can use UV-resistant window-cling film or a UV-resistant softening cloth in a round embroidery frame attached to the desk lamp.

 

Sorry for going on a bit about this, but lighting is important to our hobby, so I err on the side of too much information more often than not.

 

Take care,

Laszlo

http://hot-lead.org

[Jay]

The LED bulb's spectrum is going to depend on the mix of light emitters they use within the bulb. So I would suspect the spectrum you show may not be accurate unless it's specific to a manufacturer. Thanks for the info!

 

Oh, and what SPF level sun screen do you use? ;)

[Hot Lead]

The LED bulb's spectrum is going to depend on the mix of light emitters they use within the bulb. So I would suspect the spectrum you show may not be accurate unless it's specific to a manufacturer. Thanks for the info!

 

Yes, LEDs vary widely. I got all of the spectra from the LED Museum site. The layout is very old school frames, but if you click in the left nav menu and search "Spectra" they have dozens of analysis for light sources, including LEDs, etc. I just picked one for a product advertised as a "warm white" LED desk lamp , which was the closest the site got to an LED bulb IIRC...

 

If you peruse the entries they actually have a review for a warm white LED bulb, which exhibits a similar, though even more complete, spectrum. It's $60 though...

 

Oh, and what SPF level sun screen do you use? ;)

 

What's that?!? Oh, and why is my skin itching and these lesions keep falling off?

 

Later,

Laszlo

[Doug Sundseth]

C.R.I.

 

Companies are using color temperature as a marketing touchstone, but really you can see that natural sunlight tops out in the 3500K range, not 5500K. Color rendering index (C.R.I.) is more important - this is an industry term for how close the light emitted comes to pure sunlight. The scale is 1-100, with 100 being natural sunlight. C.R.I.s in the mid to high 90's are closest to sunlight. Ott Lites, for example, have 90-93 C.R.I. Always look for the C.R.I. listing on the bulb! If they're shy about listing it, chances are it's not "full spectrum" enough...

 

That's not quite correct.

 

CRI is based on similarity to an idealized black-body radiator. The sun is (for our purposes) fairly close, but it has emission spikes and holes. A true black-body radiator has none of these; see, for instance, this graph that shows both solar output and a black-body spectrum. Further, the color temperature of unfiltered sunlight, as shown in that same graph, is pretty close to 5250K, not 3500K. (BTW, the light in shadows and on cloudy days has a much higher color temperature, up to about 10000K, because of frequency-specific scattering by the atmosphere.)

 

The cheapest sort of incandescent (clear bulb, not frosted) is actually closer to a CRI of 100, having fewer natural emission spikes and only a very few dropouts from the glass of the bulb. BTW, daylight incandescents are much worse on CRI, though better on color temperature, because they have bulb coatings that absorb lower frequencies and reradiate higher frequencies. (See this GE page for bulb spectra for their light bulbs, for example.)

[Hot Lead]

CRI is based on similarity to an idealized black-body radiator. The sun is (for our purposes) fairly close, but it has emission spikes and holes. A true black-body radiator has none of these; see, for instance, this graph that shows both solar output and a black-body spectrum. Further, the color temperature of unfiltered sunlight, as shown in that same graph, is pretty close to 5250K, not 3500K. (BTW, the light in shadows and on cloudy days has a much higher color temperature, up to about 10000K, because of frequency-specific scattering by the atmosphere.)

 

AH! Thanks for clarifying that. It's good to know where the CRI to color temperature relationship is. The sunlight samples on the LED page were from mornings, so that makes sense. I'm not a scientist by any means, just an enthusiastic amateur!

 

The cheapest sort of incandescent (clear bulb, not frosted) is actually closer to a CRI of 100, having fewer natural emission spikes and only a very few dropouts from the glass of the bulb. BTW, daylight incandescents are much worse on CRI, though better on color temperature, because they have bulb coatings that absorb lower frequencies and reradiate higher frequencies. (See this GE page for bulb spectra for their light bulbs, for example.)

 

Again, makes sense. The coatings minimizes yellow wavelengths, but stills yield a spectrum not as complete or as rich in greens as sunlight.

 

Later,

Laszlo

[Doug Sundseth]

No problem; it's an interesting question, important to both painters and photographers.

 

I are both, and trained as a physicist (I got better).

 

The LED spectra are very interesting; now if we can just start to see the prices of high-intensity LEDs start to drop, I'll be much happier. FWIW, Ott sells a battery-powered LED lamp that works pretty well for painting, and that's much lighter than their regular lamps. I bought mine from JoAnn fabrics on sale online for (IIRC) $19.95 and have been quite happy.

[morganm]

Interesting stuff here; thanks guys for taking the time to talk about this.

 

Where does the often praised OTT light fall in here? I was hoping to see a spectral analysis of that as well. So I dug around the interweb and here's what I found:

 

Discussion and comparison to other lights: http://photo.net/digital-darkroom-forum/007Ue2

Spectral analysis:

 

 

Seems the OTT-Lite TrueColor has some big spikes as well. Despite it's large spikes; does it seem like a great light because those spikes pop up at all different wavelengths (blue, teal, green, yellow, orange, and red) Where as the N:VISION 'full spectrums' really only spike up 3 or 4 times closer together in the spectrum?

 

Am I way off here? What say you light gurus?

[Doug Sundseth]

That's an interesting set of graphs.

 

To a large extent, the appearance of paint under that sort of light will depend on the specifics of the reflectivity of the paint at those frequencies. If you have a narrow reflectivity spike in the same places you have a light spike, you'll get what looks like a very saturated color. If that same narrow reflectivity spike falls in one of the valleys, you'll get a dull-looking color.

 

The big thing, though, is that there really aren't any major dropouts like many ordinary fluorescent bulbs have. You'll get light across the spectrum, so you'll see all the colors, though at somewhat different levels than in daylight.

 

One thing to consider, though, is whether you often see your figures in daylight. (I don't, and most people I know don't either.) If you're really worried about the effect of light on paint, you should probably paint under the same kind of light you will use to view the figure. Use nasty green fluorescents for gaming figures you'll be playing with under the nasty green fluorescents in the game store where you play. Use OTT or GE Reveals for competition figures, depending on what you expect the judges to use. And use whatever lights you have in your display case for display figures you paint for yourself.

 

(Not very satisfying for me, at least, but there you go.)

[Qukel]

Don't go for CFl they will rise your electricity bills. led lights are better efficient and bright then CFL

[ThornDJL7]

So...I'm confused. Apparently I'm "dense"...which bulbs do I want now? Or better yet, which will eliminate the color distortion or at least lessen it when I take a photo?

[Kay]

So...I'm confused. Apparently I'm "dense"...which bulbs do I want now?

 

I'm with you on that... I just use a light bulb and when I paint I can see all the pretty colors... is that good?