LED shop lights?

[LCHIEN]

I see LED shop lights are selling for around $50. 4 ft specs like 4100 deg K and 3200 lumens for 38 Watts.

So T8 dual 4' fluorescent fixtures you get (2 bulbs) 64 Watts and about 5800 lumens
But the lumens are omnidirectional so the "reflectors" are no where near 100% so the effective downward illumination is a lot less. The LEDs however are directed downwards so more efficient.
I guess you would need to compare lux and even then the patterns would vary greatly.

Does that make LEDs roughly twice as efficient? effectively similar outputs for 38 Watts compared to 64 watts?

Anyone using 4 foot LED shop lights and can offer a comparison?

I have 6 dual T8 fixtures so when I run the lights I have about 500 Watts... Costs me about a nickel an hour. LEDs would save about 2.5 cents per hour.
Relamping would cost about $300 bucks so payback in 12,000 hours...
3000 days or about 8 years at 4 hours per day

T8 bulbs have a lifetime of more than 20,000 hours compared with 50,000 hours for LEDs so that's not an issue for 12,000 hours.

http://www.premierltg.com/should-you...8-led-tubes-2/

Apparently you can get LED tubes that fit T8 sockets and operate with the ballast output making it very easy to swap and upgrade bulbs, The downside is you still use the ballast and have its inefficiency and reliability to deal with.
But $7.49 per bulb, $15 per fixture.
Is 5000 degK too stark white to use in the shop?

[leehljp]

I have 2 two bulb sets now and really like the 5000K 4ft bulb lights. I have been using them for about 6 months for one and a year for the other, and I have some questions about them that have not been able to find a reasonable answer yet.

On to the question: these shop lights were advertised/listed at 5000K. When LED bulbs began coming out to home centers, I was in Japan and watched them closely. 5000K in bulbs over there and back here were "slightly but barely" on the bluish side. I tried some headlights on my car last year that were 5000K. Again bluish. However, I am finding the 5000K "color" has shifted to be more "white". My complaint is that the numbers designation does not seem to be standard. I have a couple of 4000K rated light bulbs that are slightly more "blue" than the 5000K of my shop lights. And as mentioned, my 5000K headlights are quite blue, way beyond the spectrum of my shop lights.

My complaint is that there is not the "color" standard that we expect.

As to the 5000K shop lights, I really like them over the fluorescent bulbs. I have them around my lathe where distinguishing wood color is a necessity. The 5000K shop lights render a very white light that does not seem to hinder the ability to distinguish contrasting colors.

Costco has 4000K LED shop lights for sale for $59.99 and that is for (2) two bulb sets, and without diffusers, only downward reflectors.

One advantage I am seeing among 4ft shop lights is that the tubes are not glass. I like that.

[LCHIEN]

Ugh, I took a closer look today, I have three T8 fixtures and three T12 fixtures. I'm not really unhappy, Nor is the electric bill killing me.
I think I'll just wait for a natural death of these lights.By then the LED shop lights will be cheaper, I imagine.

[mpc]

Lights now include a CRI value (Color Rendition Index or something like that) to describe how faithfully colors of objects lit by that light appear. A light source that appears white may not actually generate light wavelengths across the entire visible light spectrum, and could be generating wavelengths outside what the eye can perceive, so any missing (or at least reduced in magnitude) wavelengths (colors) will manifest themselves as inaccuracies (typically dark/muddy appearance) when viewing objects near those missing colors.

CRIs above 80 are pretty good, above 90 is great. Colors of objects lit by 90+ CRI lamps/LEDs/bulbs will look correct.

Color temperature means a light source might have an excess of red or blue wavelengths... but you still hope the light source generates all wavelengths in the visible spectrum.

mpc

[cwsmith]

Loring,

Thank you for the excellent and timely post.

I am in the midst of seriously thinking about installing LED shop lights to replace in temporary 4-ft florescents that I presently have in the new shed. I put two new florescents in back in August and already one of the tubes has gone bad. I bought the T8 bulbs at Home Depot and they just don't seem to last all that long (maybe 2 years), and this particular failure was no doubt a bit premature.

I've looked at HD and Lowes and I like the diffused units at Lowes. They're about $50 per fixture and, at least in the display, seem to be brighter than my current florescents, though having them side-by-side would offer a better evaluation.

Temperature-wise, I seem to recall that 5,000 K was what one would seek in a photographic situation. IIRC, that is the temperature of 'daylight', at least as the "Standard" for what is termed as "Daylight". (As I recall, it was the light temperature scientifically measured at the Washington Monument on a particular July 4th... or so the story goes! With all other light sources graded warmer or cooler based on that standard. So, a 5,000 K bulb is supposedly close to natural daylight and thus provide for best color rendition. ( https://en.wikipedia.org/wiki/Color_temperature )

The biggest concern I might have with LED light is possible glare. I know my local Lowes has some security/yard style llghts set up in their lighting aisle and they will practically blind you when you walk past that isle. (I actually complained to the manager, to have them positioned differently, as they were so blinding.)

The shop lights are more diffused and I would hope offer a pretty decent lighting situation for the shop. Sometime in the next two weeks I hope to buy a couple and then see for myself.

BTW, there are a few videos on YouTube that discuss this comparison.

Thanks again for the post,

CWS

[leehljp]

The biggest concern I might have with LED light is possible glare. I know my local Lowes has some security/yard style llghts set up in their lighting aisle and they will practically blind you when you walk past that isle. (I actually complained to the manager, to have them positioned differently, as they were so blinding.)

The shop lights are more diffused and I would hope offer a pretty decent lighting situation for the shop. Sometime in the next two weeks I hope to buy a couple and then see for myself.

BTW, there are a few videos on YouTube that discuss this comparison.

Thanks again for the post,

CWS

It may be just me, but, in pen turning, specifically in finishing, I find a direct overhead diffused light to be a big hindrance. Diffused light reflects off of the fine finish like a thousand points of light - when what is needed is for the light reflection to be continuous and smooth. Without the smooth reflection it is hard to tell if there are imperfections in the finish or if it is the multifaceted diffusion reflection. A smooth diffuser is OK.

[LCHIEN]

Loring,

Thank you for the excellent and timely post.

I am in the midst of seriously thinking about installing LED shop lights to replace in temporary 4-ft florescents that I presently have in the new shed. I put two new florescents in back in August and already one of the tubes has gone bad. I bought the T8 bulbs at Home Depot and they just don't seem to last all that long (maybe 2 years), and this particular failure was no doubt a bit premature.

...

Thanks again for the post,

CWS

Lifetime of T8 bulbs is claimed to be 20,000 and for some, 30,000 hours. There are about 8000 hours in a year, counting 24/7 operation so that is 2.5 - 3.5 years of 24/7 If you got 2 years of 4 hours a day that is only 3000 hours...
Was it the bulb or ballast?

[LCHIEN]

CW you can get T8 LED replacements that operate off the ballast outputs and basically plug into the T8 sockets. Two bulbs for $7.50 each, I saw.
Give you the advantage of LED light without making any physical changes (fixture), just plug and play. A little less efficient but cheaper and easier than 4' LED fixture.and still much more efficient than T8s.

[cwsmith]

Thanks.

I've got to go to Lowes this afternoon, so I'll check to see if either they or Home Depot have the individual LED replacement tubes. That would be significantly less costly.

CWS

[cwsmith]

Delayed with the snow storm on Monday, so finally made it yesterday. The bulbs at Lowes are 4300 K and a bit dimmer. Checked the online reviews and they didn't do well. Also checked my local Home Depot, and though listed online, they don't carry them in the local Binghamton, NY store.

Guess I'll buy one of the regular LED shop lights after Thanksgiving and see how it compares.

CWS

[capncarl]

We replaced the t8 bulbs in our laundry room fixture with led tube light that used the existing ballast. It seems like more and better light. After we did this I talked to several of the maintenance men on the base, they said that they had replaced 100s of t8 and t12 with this bulb and hadn't had to go back and replace any ballast. It seems that the led must be easier on the ballast or something.

[LCHIEN]

Yeah, the ballast only has to handle roughly half the power - less current, less heat, they should last forever.

[LCHIEN]

Color Temperature
5000°K is described as Stark White
4100°K is described as Daylight, slightly blue
3000°K is described as Warm, slightly yellow or amber

[leehljp]

Color Temperature
5000°K is described as Stark White
4100°K is described as Daylight, slightly blue
3000°K is described as Warm, slightly yellow or amber

The charts I use and see most often show the blue as 5000° and white at 4000°.
the higher the number, the more blue until past 6000 it begins to be purplish.

1900K Candle light or sunlight at sunrise or sunset
2000K - 2700K Often used as accent lighting to blend in with fluorescent 2700K applications.
3000K - 3200K Used as a primary light source for retail applications.
3700K Coated lamps. Used where a "softer" metal halide light source is desired.
4000K Used in general lighting; factories: parking lots, warehouses
5000K - 5500K Daylight lamps: horticulture, aquariums, high color definition.
5600K Nominal sunlight (mid day during mid summer)
6000K Starts to get a blue tint like some automotive headlights

On my car, I had 5000K headlights that were bluish and changed them back down to 4000K, which were more white, - i.e. "not" bluish.


This is why I say there is not a standard on the "K" number yet.

[cwsmith]

Apparently the lack of "Standard" enforcement allows these manufacturers to quote any light temperature number. One would think that a product giving such a specification would have been tested to verify such claims.

CWS

[cwsmith]

Back in the early 80's (ancient, I know), I bought an 'Acculight' light box used for sorting 35mm slides and also for photographic back lighting. It came with two B-Knox florescent bulbs which were rated at 5,000 K. At that time, the 5,000 Kelvin light value was considered the 'standard' for daylight photography. These bulbs were expensive and about the only source that I had was a couple of pro retailers in NYC. I did a quick search and I don't find those particular bulbs available anymore. I do have one bulb left that's pretty much dead now. I don't do any of that kind of photography anymore, as new technology has long since replaced the need. The old light box is still in use though as I sort through a few thousand old 35mm family slides.

CWS

[poolhound]

I have a few of the costco dual LED shop lights. I think they were approx $30 each. I also have a bunch of regular florescents in the shop and garage. Not considering changing them out until the tubes go and I have a box of spares to get through too.

[LCHIEN]

I ordered one of these for under $30 just to see what its all about.

https://www.amazon.com/LUCECO-3600-Lumen-LED-Shoplight/dp/B01H2LXB78/ref=pd_lutyp_simh_2_3?_encoding=UTF8&pd_rd_i=B01H2LXB78&pd_rd_r=GQYAB4KDWA04MNAF0M2X&pd_rd_w=cXSo6&pd_rd_wg=zCAUI&psc=1&refRID=GQYAB4KDWA04MNAF0M2X

[havighurst]

Loring,

I would be interested in your impressions after you try them out.

Mark

[atgcpaul]

I converted a couple of my T8 4' shoplights and our kitchen light to direct wire and installed some LED tubes for $20/fixture. I think they're brighter and now that it's a touch colder, the lights don't take any time to come to full brightness.

I also bought a couple of the FEIT LEDs from Costco when they were on sale for $25. They are nice but the tubes aren't replacable. Hopefully that won't be an issue. I just saw in the newest Costco ad that they'll be $20. I'm going to get some more.