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View Full Version : Fluorescents are a bad way to light a woodshop



Jamie Buxton
10-17-2005, 1:19 AM
I’ve recently been teaching in a shop which is lighted with fluorescents, and it reminds that they’re a terrible way to light a woodshop. They have two bad characteristics:


1) Bad color

I love wood. Among other things, I love it for its color. Almost all the standard cabinet woods turn weird ugly colors under fluorescents. That rich red cherry turns ugly brown, maple turns kinda green, walnut just goes flat, and the list goes on. It is just lots less fun to work with wood under that light.

In addition, any part of the job which requires color sensitivity --- for instance deciding which planks to use near each other --– is difficult to do under fluorescents. And don’t even think about stains or dyes; they often look way different under fluorescents.

(And oh by the way, the color rendering index which fluorescent manufacturers push is hogwash. While it is true that a lamp with a CRI of 92 is better than one with a CRI of 60, it is still bad. For a while, I had a shop lighted with the highest CRI lamps I could buy, but they were still a very different color from sunlight.)



2) Diffuse light

The large size of fluorescents naturally produces diffuse, even, lighting. That’s a bad thing in many woodshop operations. A point source like an incandescent is much better. Here’s some examples of where a point source is good:

Edge-gluing planks. With a point source at a nice flat angle, misalignment of the planks is easily seen by the shadow at the edge of the plank. Triming solid edgebanding is similar.
Jointing. You want to make passes on a jointer until the jointer hits everyplace along the edge. This is easy to see if you hold the plank up so that the light glances along it, and unreliable under fluorescent.
Sanding. With a point source at a low angle, it is very easy to see sanding scratches. Under a diffuse light they often escape –-- until the furniture goes into a home someplace where sunlight or a lamp exposes the mistake.


Another bad effect from diffuse lighting is that chatoyance is greatly diminished. Chatoyance really wants a light which is a point source, so that the reflection changes when you move your eye. With a diffuse light source, there’s no change when you move your eye. The result is all that beautiful curl disappears under fluorescents, and again some of the pleasure goes out of woodworking.

The better way to light a shop is halogen floods. They provide better color and chatoyance, and help you do better work.

Jamie Buxton
10-17-2005, 1:49 AM
Utilities strongly push fluorescents because “they are much more efficient” --– that is, they’ll cost you less to light your shop. Let’s run the numbers on two cases…

1) A two-car garage lit with 12 65-watt halogen floods. That’s a lot of light. The light is consuming 780 watts of electricity. The average cost of electricity in the US is about 8 cents per kilowatt hour. That is, this lighting costs 6 cents per hour of operation.
2) The same two-car garage lit with the same amount of light from fluorescents which have a high color rendition index (90 or better). High-CRI fluorescents are about three times as efficient as halogens, so this lighting would cost about 2 cents per hour of operation. Put a different way, the halogens cost 4 cents more per hour of operation.

Let’s say the shop lights are on 500 hours in a year. The annual extra cost for the halogens is $20. That’s darn puny in return for a big improvement in darn near everything we do in a shop.

Dan Forman
10-17-2005, 4:39 AM
Jamie---I agree that high CRI readings are deceptive, the higher numbers give a distinctively cold (blue cast) light. That's why I've been cautioning those who are talking about T-8 lighting. But you can get pretty close with a combination of T-12 "warm"(yellow cast) and "cool" bulbs, one of each per fixture. They really balance each other out, filling in the deficiencies of each individual bulb. I'm an artist, and that combination is the best I've found to date as far as color accuracy goes.

I also agree with you that it is good to have at least some point source lighting too for the sort of tasks you mentioned. But often times for other activities that can be distracting as well, especially if one has low ceilings such as in a basement. It can lead to unwanted glare.

Halogens give off much more heat than flourescents, which can be a blessing or a curse, depending on the season and shop location. Interesting figures on the cost element, the extra energy must be converted to heat, but it doesn't seem to put much of a dent in the wallet.

Probably the best solution would be a combination of sources to suit the task at hand. I have been very happy since adding five flourescent fixtures to my basement shop, each equipped with one warm and one cool high output T12 bulbs. I have a couple of incandescent ceiling fixtures which were there to begin with, as well as a portable clip-on lamp for when a point source is needed. I may try adding a halogen flood or two just to see what will happen, but the combo of warm and cool bulbs works well for most things, and is much easier on the eyes than standard flourescent lighting.

Just offering this as something for people to think about, not trying to convert you! :eek: :D

Dan

Jeff Sudmeier
10-17-2005, 8:49 AM
:) Wow I never knew I wasn't having fun in the shop!!

That said, I use florecents, incandesents and a hallogen lamp. I set up the hallogen lamp when I am sanding or other fine work. For the rest, the florecents work just fine.

lloyd morris
10-17-2005, 9:36 AM
Jamie,Thanks for the information regarding fluorescent lighting. My wife is a physician who sees and treats a lot of people who experience the negative physical effects of fluorescent lighting in the workplace. By far the most common problems she sees with fluorescent lighting is eye strain and migraine headaches. The problem is much more common is in environments where the only light source is fluorescent lighting as opposed to several light sources including natural light.While I have not had any physical problems from fluorescent lights in my small shop, I switched over to a combination of incandesents and a halogen lamps last year and noticed a big difference all the areas you mentioned. Thanks,Lloyd Morris

Larry Browning
10-17-2005, 10:06 AM
I have nothing but T8s in my shop. I never knew that I was unhappy with them. As far as I was aware they worked great. I guess I just don't know any better. All I know is that I used to have 2 8ft T12 fixtures in my 2 car garage "workshop" which produced terrible lighting. When I built my new 30X30 workshop i installed 12 8ft T8 fixtures. And up untill I read this post I had perfect lighting. There are no shadows no matter where I am in the room and they don't hum at all. The don't produce much heat, which for the most part here in Arkansas is a good thing. And the best part is I can actually SEE what I am doing. My projects seem to come out of my shop looking the same color as they were in my shop.
This post makes me think that sometimes I might be better off not knowing negative things about stuff I thought was as good as it could get.

lloyd morris
10-17-2005, 10:44 AM
Larry,I think you raise a good point. You probably do have perfect lighting for you and your shop. Everyone's eyes are different and many, possibly even most people get a very good result with fluorescent lighting. I did not have T8s in my shop and am glad to hear the work well for you.Lloyd Morris

Tim Sproul
10-17-2005, 12:36 PM
Let’s say the shop lights are on 500 hours in a year. The annual extra cost for the halogens is $20. That’s darn puny in return for a big improvement in darn near everything we do in a shop.

Conservation is more than just what you, as an individual, save. If every customer of the electric grid didn't give a hoot about $20 savings here and there......we'd not have an electrical grid anymore. Heck....think about how bad the oil situation would be if we all drove vehicles that only got 10 mpg because going to 30 mpg would only save us a few hundred a year......


I agree that fluorescent lighting isn't ideal for everything. I disagree that it is unworkable. Fluorescent lighting works well for ambient lighting and should be supplemented with task lighting as needed. Those $20, 500 watt halogen work lights are great for finishing. Get the $40 version and they come with a stand......I'd also wager that fluorescent lighting is the preferred alternative for hobbyists because you can easily surface mount fluorescents. It is a much more involved task to install can lighting in an existing structure - especially if you don't have attic access.

Larry Browning
10-17-2005, 12:40 PM
Sometimes this forum is very frustrating to me. It seems that no matter how much research I do and how hard I try to do things the proper way and to make good decisions on how to spend my time and money, there is something I didn't consider or some better "thing" I should have bought instead of the one I did. Sometimes I think that maybe I'm just better off not knowing I screwed up. The saying "ingorance is bliss" is really true.
But, even with that said, The information here is truly outstanding and the quality of the projects I turn out is much better because of this forum.

Larry

Dick Heifner
10-17-2005, 12:54 PM
Hello all,
What is the difference between t-12 and t-8 fluorescent lighting ? I seem to be in the dark about half of the time in my shop and have 2- 8 ft, t-12 fluorescent lighting fixtures.
Thanks ,
Dick

John Bush
10-17-2005, 1:21 PM
Hi All,
We use "color corrected" fluorescent bulbs that seem to eliminate the green and blue cast found in conventional fluorescents. We are able to match natural colors well and the illumination is good. I think the bulbs are classified as 5500K and are manufacured by Durotest. Kind of spendy compared to the conventionals but appropriate for us. Good luck, John.

Tom Hintz
10-17-2005, 1:42 PM
When I first built my current shop (converted the garage when the wife was away) I began by lining the ceiling with flourescent fixtures. Two years later, after fighting with them non-stop, changing builbs, ballasts and the occasioanly fixture I outright assasinated, I ripped them all down and tossed em. Now I have incandescent lighting throughout, I can see better than ever and if it is costing me .04 or .05-cents per hour more, so be it. I can die poor but happy.

Joe Pelonio
10-17-2005, 1:46 PM
Another disadvantage to flourescents is that they have the additional maintenance cost/time for the ballasts and starters. My inside shop and showroom are 4 bulb 4' fixtures (suspended ceiling) and out in the warehouse/woodworking part is dual bulb 8' flourescent that
are 16' up. Not easy when you can't tell which bulb is bad or if it's the starter or the balast. I use halogen floods on a stand for supplemental
light as needed and when dealing with a customer on color often step outside into the natural light. For a computer area the Ikea hanging
halogens are great.

Kevin Post
10-17-2005, 2:18 PM
I have a combination of fluorescent and incandescent lights in my shop. I'd rather have windows but...

One thing that hasn't been mentioned is how cool it is when the tablesaw blade grabs a hold of a tiny, offcut piece of wood and fires it at the ceiling where the 8 ft fluorescent fixtures live - *PINGGGG* - *CRASH*. :eek:

DAMHIKT

Roger Myers
10-17-2005, 2:19 PM
I always try to stay out of these lighting threads...but....

Some basics... (maybe more than you want to know, but not as much as you need to know)

Bulb sizes/shapes are generally designated with a letter and a number - in the case of linear fluorescent lamps, this is a T (for tubular) plus a number which designates the size in 1/8's of an inch. Hence, T-12 is a tubular bulb that is 12/8's of an inch in diameter and a T-8 is the same shape but only 8/8's of an inch (or 1") in diameter {you thought lumber yards were the only ones to mess with things like 5/4 :) }. There are also newer (becoming very popular in industrial and commercial applications) T-5 bulbs (yes, 5/8" in diameter) and there are also special purpose T-2 fluorescent lamps (display cases, etc). By contrast, the traditional automotive tail lamp bulb is referred to as a S-8 lamp (spherical shape, 1" in diameter). Length of fluorescent lamps in the US is generally 4' or 8', but there are other sizes as well.

Ballasts - T-12 utilize magnetic ballasts. T-8's and T-5's use electronic ballasts (there are exceptions, but not for the most part.) T-8's are lower wattage and more efficient lamps. With the right ballast and controls they can also be dimmed if needed. T-12 lamps and magnetic ballasts WILL be going away. They are already gone (by legislation, due to energy efficiency) for new commercial installations, and will continue to disappear from the lighting landscape, replaced by T-8 and T-5 lamps and ballasts. "Shop lights" sold at low prices with T-12 lamps are generally very poor performing magnetic ballasts. Electronic ballasts for the most part are high quality, flicker free, very efficient power supplies.

Different colors of light (think warm white, cool white, daylight, etc.) are available in both T-12 and T-8 and are a function of the phosphors used in the lamp. This is the color temperature you will see referenced....lower number is "warmer", higher number is "cooler". CRI is the all important color rendering index... higher number brings you closer to natural light, or full spectrum. All lamps will favor some part of the spectrum more than others... incandescent (think 60 watt screw in bulb), halogen (still an incandescent but operating at a much higher color temperature ) fluorescent (available in different many different "colors") discharge lighting (HID, including sodium, mercury, metal halide)....

Energy savings... think first in lumens/watt... all lamps consume energy to illuminate and that will be the wattage of the bulb. However, only part of that energy is converted in light... the rest is heat. Not only do you need to think of energy savings in terms of watts used to create light, you must also consider the energy it takes to eliminate the heat... (and yes in the winter, the heat is nice, but it is not an efficient heat source).

Life... Look at the life ratings for the products and factor that into your cost base, if you want to see the full impact... halogens generally have much lower life ratings and the replacement costs can be high.... (bear in mind that life ratings are average life, not minimum life).

Diffuse vs raking light.... I like even workshop illumination for general workshop conditions.. few shadows, high illumination. For some tasks, especially carving, raking light is very very valuable. I have track fixtures mounted over my workbench and next to my lathe with adjustable halogen fixtures on them that I use when I need this additional light or raking light. I do not leave them on all the time.

So what color temp and CRI?? The higher color temp fluorescent and higer CRI bulbs will give you light most closely simulating daylight....Better than incandescent and better than just halogen. That said, nothing beats natural light.... As many windows and skylights as you can have, along with light painted walls and ceilings. I do have a few halogens that I turn on if I need spot illumination.

Next time you are in a grocery store, especially a large chain...look at the lighting... will normally be different over the produce aisle... They are using lights which make the fruits and vegtables look their best. In a good jewlery or furniture store, they will select very specific lighting to make the best advantage of the colors in their products (diamonds like brilliant white light...but that isn't the best for gold...)

There is a great deal more to the science of lighting and I have yet to see a really good article (some have come close - the last FWW article wasn't bad) on the subject of lighting in woodworking shops and schools.... One of these days I may find the time to consult with our experts and create a definitive article... In the meantime, there is good information on the sights of the major lighting companies, including the one I work for.

Find what works for you...very few absolutes... more light is better.... natural light is best....

And fret less about the lighting and enjoy woodworking!

Roger

disclaimer - I do work for a major lighting company that makes the bulbs (incandescent, fluorescent, hlaogen, discharge, LED), as well as the glass, the phosphors, the ballasts, the bases...... We make all of the different types of lighting, so I am not swayed by what we produce... only the science of lighting.

Aaron Koehl
10-17-2005, 3:22 PM
I always try to stay out of these lighting threads...but....


I was actually waiting for you to chime in! ;) Very informative, thanks again!

Dan Forman
10-17-2005, 3:30 PM
Roger---Thanks for your info. I had looked locally for different color casts in the T-8's, but could only find "cool", so assumed that was all that was being made at this time. Still, for those on a budget and not adept at wiring, the low-tech "shop lights" are cheap, easy to hang, and only need to be plugged in.

Dan

Roger Myers
10-17-2005, 3:41 PM
Aaron - As I've said before.... I hate going there but.... :)

Dan - As I finished my post with...do what works and be happy & be woodworking :)
Also, check at any good lighting or electrical supply (like a CED), or even on line for different bulb types...they do exist..they can also be pricey..

By the way, those 18th century cabinetmakers made some pretty fine pieces of furniture without all this newfangled stuff we obsess about :) Couple of guys named Goddard and Townsend and many others did superb work that I'd be very proud to call my own... Wonder if they had these same discussions but were debating hurricane style lamps compared to candles, compared to whale oil...well, you get my point :)

CPeter James
10-17-2005, 4:07 PM
I have just converted almost all of my house and shop lighting to T8 type and the savings is paying to run the electric hot water heater that I use in the summer so I don't have to run my oil boiler from May until November. To date they have been quite satisfactory.

CPeter

John Gornall
10-17-2005, 4:34 PM
I'm one of those odd fellows that actually reads the instruction sheets.

18 years ago I relit my shop and the instructions for the lights, T12 - 8 foot, suggested that the lights should not be switched off for the first 48 hours to avoid humming and short life. I did this and after 18 years no ballast has failed but I now have a bit of a hum from a couple.

I relit the showroom area last year with T8 - 4 foot and electronic ballast using "Daylight" tubes. No heat, no hum, and with a few added halogens the color suits me fine.

Using a light meter I found that 3 - T8 tubes give me the same light as 4 - T12 tubes - along with the electronic ballast it's a good energy savings.

Jim O'Dell
10-17-2005, 4:40 PM
Roger, thanks for the info. I for one am ready for the full article!!! I'm in the middle of my lighting set up right now, and the more information I can get, the better decisions I'll be able to make. Jim.

John Bailey
10-17-2005, 4:48 PM
Roger,

I second the motion of the full article. I'm building my shop, just getting ready to have the electric hooked-up, and I'm starting to look for lighting. I spent about an hour at Home Depot the other day and got confused as heck. So, any info will be good.

John

lou sansone
10-17-2005, 5:05 PM
Roger
thanks for weighing in on this. I was also going to take a stab at clearing some of this up, but you have done a good job.



I would like to ask jamie what facts he could provide to support his claim the "CRI is hogwash".

lou

Dave Lehnert
10-17-2005, 5:14 PM
Not too long ago I read a report that Florissant lighting in a wood shop could be dangerous. Something about how a Florissant light flickers at a fast rate and a saw blade turning at 4,000rpm’s can make the saw blade look like it is standing still and not spinning. This was in one of the woodworking magazines. Maybe someone knows more about it.

Frank Pellow
10-17-2005, 5:43 PM
Roger, I really appreciate the "tutorial" and would be happy to see a lot more from you on the subject.

My shop has lots of daylight in the daytime but, at night, I am VERY HAPPY with my T8 C-50 lights. They are quiet, light instantly at very low temperatures, don't cost much to run, and are close enough to daylight for me.

JayStPeter
10-17-2005, 5:47 PM
I use some bulbs with (I'm trying to do this from memory) 92CRI and 6000K. They are made by Sylvania and are easily ordered at my local electrical/lighting place. They are significantly more expensive than std cool white bulbs, but not real bad (around 2.5x cool white if I remember right). Both HD and Lowes sell a T-12 bulb that is close, but usually not stocked in large quantity. Mine are T-8 and I have to buy them in qty 25+. Since I have ~20 2-bulb fixtures this isn't a real burden. Surprisingly, my local joint charges significantly less for these bulbs than any of the "discount" bulb places on the 'net I could find.

Fortunately, I did my homework before building my shop. I bought 4' fixtures instead of 8' because I couldn't find a reasonably priced supplier of "daylight" bulbs in 8' lengths. The only ones I could find on the 'net charged more for shipping than the bulbs themselves. Unfortunately, I had to go to cheap buzzing fixtures to stay even close to the budget that was originally planned with 8' fixtures. I do have some incandescent fixtures placed over my large worktables as well as some smaller task lights.

Jay

Randy Meijer
10-17-2005, 5:50 PM
Roger: I spent several hours, last night, searching the Internet for some simple numbers that seem to be necessary to use the various lighting design calculators that are around. I understand that lighting is a very sophisticated subject with lots of variables to complicate the issue. What i am looking for are some "ballpark figures" to get me in the range as far as my light requirements. Can you suggest a good web site that will help?? Seems that all of these calculators want to know how much light is need at the work site. They ask for it in different units...lumens, candle ft, etc; but I have yet to find a site that will tell me the recommended lighting level for a shop or a kitchen or for reading or for sewing or other close work. I assume these numbers vary somewhat depending upon personal preference; but I sure would like to find some numbers to use as a starting point. Thanks,

Chris Fite
10-17-2005, 6:04 PM
Not too long ago I read a report that Florissant lighting in a wood shop could be dangerous. Something about how a Florissant light flickers at a fast rate and a saw blade turning at 4,000rpm’s can make the saw blade look like it is standing still and not spinning. This was in one of the woodworking magazines. Maybe someone knows more about it.

I have never experienced the strobe effect making a spinning bit or blade appear to stand still. I have noticed that no light source prevents the tool from making noise.

I have often wondered where the break-point is in the balance between windows and sunlight for a shop and the cost of heating with the low insulative ability of windows. Of course, windows provide nothing in the way of light when it is night.

This forum always provides more food for thought. I started with the high bay lights in my new shop. I found that there was lots of light but it seemed diffuse everywhere. I get the constant sensation of being in a shadow under these lights. Two of the four have failed, the transformers died. I think that I may be better off now that I can try some of the newer T-8 fixtures and perhaps some halogen. I have a ways to go on the learning curve dealing with ceilings at 12 feet. Do I mount the lights below the ductwork for the dust collector or will the ductwork present a problematic shadow with the fixtures mounted on the ceiling above the ductwork?

When I wired the shop, I provided for several individual task lighting areas. It may be that varying the types of lighting by area will provide the benefits that I need.

Jim O'Dell
10-17-2005, 6:08 PM
For those interested, I have found a site that has the 95 CRI 4' T8's for 97.50 for a case of 25. Shipping to me was another 15.00 or so. This put them just a little over the price of the HD cool white T8 2 packs at 6.97 plus tax. They also have the 86 CRI at just under 50.00 per case of 25. I'm at work now, but let me know and I'll send you the website addy. I've never ordered from them, so take the info at your own risk. Jim.

Jeff Fritzson
10-17-2005, 6:27 PM
Randy,

Try Googling with the following - "foot candles" workbench height woodworking - and you should see some interesting reading about the number of "foot-candles" desired at a workbench height for a number of applications. Using this research is where I came up with 100 foot-candles for my preference. I used that and a lighting estimator to put 6- 8 foot fixtures with 4 - 4' T8 bulbs 86 CRI in my 22 x 22 shop with 10' ceilings.

I have not had any issues with "blue" coloring, chadows, flickering, slow starts, or anything else previously mentioned. I am open to spotlighting certain areas if I ever feel the need but so far none has occured. This works for me but may not for everyone else. I have not yet done any specific finishing, or detailed coloring so I cannot attest to how my lighting will work under those requirements yet.

Jeff

Sam Blasco
10-17-2005, 6:46 PM
I switched to the daylight bulbs several years ago and I'll rave about them. It's almost like working on the patio. I still, and always have, use task lighting too, both standard bulbs and halogen. Whatever works, I just make the dust and ask questions later.

Aaron Koehl
10-17-2005, 8:26 PM
Aaron - As I've said before.... I hate going there but.... :)


Well, you're certainly one of the experts! So when are you going to be in Williamsburg again?

Roger Myers
10-17-2005, 8:46 PM
Well, you're certainly one of the experts! So when are you going to be in Williamsburg again?

Aaron - I'm not making the SAPFM conference in January because I've simply got too much on the plate but I hope to come down in the spring with SWMBO and just enjoy Williamsburg and the area. I'll be sure to be in touch when we visit.

Dave, fluorescent lamps on electronic ballasts operate at a high frequency..on the order of 25,000hz or more, depending on the ballast. There is no strobe effect that I have ever observed, or heard factually reported, but remains one of those urban legends... Probably dates back to the magnetic ballast/early flourescent days when flickering was more of an issue, and there were concerns with headaches, etc. Lighting in grade school was horrible...and yes, that was a long time ago ;)

As to an article, as time permits I'll try to cobble one together, but frankly time is a very precious commodity at the moment, so don't look for anything in the next few weeks.

Jay - an excellent choice on the bulbs ;)

Roger

David Pettibone
10-17-2005, 8:47 PM
Hello

If I have 4 foot fixtures, can I find daylight bulbs to fit in them and can I only find them at a fine lighting store versus a Home Center??? I have the regular Home Depot shop fixtures from 1999:eek: and my shop is heated. I just buy the regular 40 watt light bulbs to go in them, cool white I believe. So again if you would, where do I find 4 foot daylight tubes to go in my fixtures? Thanks a jillion!!!!!!!!:) :) :)

Gratefully, David

David Klear
10-17-2005, 9:21 PM
I've been considering this same thing but don't like to use the halogens because of cost and fear of fire hazard.(They get hot!!) Is there another kind of task lighting that can be used instead of the halogen. Could you sue some of those outdoor lights that they use for area lighting at night. Or Floods and spots Just wondering???

Randy Meijer
10-17-2005, 9:23 PM
Jeff: I googled until I was Ga-Ga!!:D I searched all of those terms and more and probably looked at over a hundred sites and never found what I was looking for. That 100 ft-candle figure will be very helpful. Thanks. Was that a high figure, low or about mid range??

Roy Wall
10-17-2005, 9:24 PM
Hello

If I have 4 foot fixtures, can I find daylight bulbs to fit in them and can I only find them at a fine lighting store versus a Home Center??? I have the regular Home Depot shop fixtures from 1999:eek: and my shop is heated. I just buy the regular 40 watt light bulbs to go in them, cool white I believe. So again if you would, where do I find 4 foot daylight tubes to go in my fixtures? Thanks a jillion!!!!!!!!:) :) :)

Gratefully, David

David,

I just saw T-12 lamps in various "colors" (3500k to 5500k) 5500 k is daylight approx.---------this was a Lowes store...

I bought T-8 lamps; my only choice was 4100K lamps......they'll do....

Jamie Buxton
10-17-2005, 9:37 PM
I would like to ask jamie what facts he could provide to support his claim the "CRI is hogwash".

lou

Lou, that assertion is based on what I see with my own eyes. The manufacturers say "CRI=100 is sunlight", and the implication of a CRI of, say, 92, is that it is darn near as good as sunlight. The manufacturers want to foster that belief because they think it will sell more bulbs, or make people happier with their product. However, as I look at CRI=92 bulbs, their effect is quite different from sunlight.

Jamie

lou sansone
10-17-2005, 9:56 PM
hi jamie
fair enough, you don't feel that what you see under the lights with a CRI of 92 is
as decent as sunlight. I don't think that it is real clear if this CRI scale is linear or some logarithmic or other type of scale. If for example is was "log like" then for each 3 units from 100 you would have a sensation of 1/2 of the original color quality, this would be in contrast to a linear scale that would require 50 units to become 1/2 the color quality.

These couple of web sites should at least show that trying to determine CRI is not just some dorkey guy sitting at a table making up stuff in order to sell light bulbs. It does look like there are some real metrics behind the process. the second web site is interesting in that it shows that CRI has to be matched to the color temperature of the bulb and the solar condition in question.

As others have said, a combination of lighting technologies seems to be most usefull overall. I would agree that low CRI bulbs leave much to be desired, but I have found that high quality CRI bulbs do a pretty decent job. I would also highly recommend adding as much north facing sunlight in a shop as possible.


http://www.kruschwitz.com/cri.htm

http://www.scsolar.com/PDF_Files/Color_Temperature_and_Color_Rendering_Index.pdf

enjoy
lou

Kelly C. Hanna
10-17-2005, 10:10 PM
I completely agree...I have but one reason.

Very few view fine woodworking in flourescent light at home....why use that light to build anything?

I prefer the warm lighting of incandescant bulbs...in the other lights I feel like Joe in Joe versus the Volcano....brain clouds.....

Allen Bookout
10-17-2005, 10:13 PM
I agree with Larry Browning and Sam Blasco. I have eight foot t8s (4 48" bulbs per fixture) with electronic ballast and daylight bulbs wall to wall. If you use the right fixture one bulb being inoperative will not shut down any others. Great light with good color and no shadows. They are instant on and no noise and they also do not create any heat which is a blessing anywhere air conditioning might be desirable. It feels like I am outside in bright daylight when I am using them. I had some halogen lights and threw them away because I hated them.

If you want to color match something just take it to another room or outside if you are not able to see with the flourescents. Does not sound too hard to me.

As for headaches, I am sixty three and worked in the sun and under lights for years and have never had any problems in that area. Sounds like the headache thing is some sort of medical problem. Take two asprins and see your doctor.

The point is if you are going to light or relight your shop do not take the word of one person. Either go to a shop or room and take a look for yourself. Or, better yet, try just one of two of each kind of light and see for yourself. If I were a betting man I would bet ten to one that you would come away with quality flourescent fixtures with electronic ballast and daylight bulbs.

Allen

Allen Bookout
10-17-2005, 10:21 PM
Hello

If I have 4 foot fixtures, can I find daylight bulbs to fit in them and can I only find them at a fine lighting store versus a Home Center??? I have the regular Home Depot shop fixtures from 1999:eek: and my shop is heated. I just buy the regular 40 watt light bulbs to go in them, cool white I believe. So again if you would, where do I find 4 foot daylight tubes to go in my fixtures? Thanks a jillion!!!!!!!!:) :) :)

Gratefully, David

David, I found some at my Home Depot and are listed as daylight. They just showed up a few weeks ago.
You might check with the manager at your store or look at their internet site. Allen

David Pettibone
10-17-2005, 10:32 PM
Thanks a lot. I am going tomorrow to check out what they have in stock at both Home Depot and Lowes. Thanks for the info on what temp.(5500k) defines a daylight tube. That's what I will be looking for.:)

David

Roger Myers
10-17-2005, 10:36 PM
Okay folks....
This is why I hate going into these topics......

CRI is NOT some manufacturers devious marketing technique, but is actually a very definitive measurement and of significant value to lighting designers, architects, and lighting engineers.

For more information on lighting topics in general, without a focus on any one manufacturer, I might suggest you start with the Lighting Research Center at Rensselaer

http://www.lrc.rpi.edu/

There is a ton of information there.

I'm done with the subject..if you have serious questions, feel free to PM me and I'll attempt to answer them factually or point you to a source that will have answers.

Roger

Dan Forman
10-18-2005, 3:07 AM
Some of you might find find this site interesting. I was looking into these for painting a while back, but they only had the low voltage bulbs at the time. Probably not a necessity, but interesting none the less. Check out their list of customers.

http://www.solux.net/

Dan

John Bailey
10-18-2005, 6:09 AM
Lou,

Lotsa' northern light is why I made my entire northern roof plastic. It's great. Terrible for insulation, but great for the eyes. I don't have any lighting right now. I've been working out there for two months and the natural light is terrific, even on cloudy days. Of course, work stops when the sun goes down.

Roger,

Thanks for all the info. Like most, I take into account all suggestions, pro and non-pro, from this site, then, make up my own mind what's best for me. After all, I'm the one who has to work and play in the shop.

The best advice so far has been "I'm one of the odd fellows who actually reads the instruction sheets." Thanks John, for reminding me. I'm one of the regular guys that needs to be reminded by one of the "odd" guys.

John

Dave Anderson NH
10-18-2005, 12:49 PM
My buddy Roger Myers has at every opportunity over the years mentioned over and over how he refuses to get involved in any discussion on lighting. I just had to take this opportunity to bust his chops and observe that you should never say never. For those of you who think I might be a bit on the harsh side, you have to understand a little bit. He has busted MY chops for years about the cleanliness level of my shop and about whether or not I ever do any woodworking in that "pristine atmosphere". I figure that turnabout is fairplay.

As for Roger's credentials. He has been in the lighting business for well over 20 years at every level from quality engineeer to plant manager. He is currently the VP of Quality at one of the 2 or 3 largest manufacturers of lighting in the world. In deference to his sense of propriety, we won't mention which one.

Finally, it's bust 'em time again. Gotcha Roger!!!!!!!!!!!!!!!!

Roger Myers
10-18-2005, 1:45 PM
Finally, it's bust 'em time again. Gotcha Roger!!!!!!!!!!!!!!!!


Thanks Good Buddy.... There will be payback!

By the way Dave, I know you said that during Sue's unexpected time off she hemmed the curtains in your shop, but I don't think that I or my fellow creekers have seen pictures of them yet :)

John Bailey
10-18-2005, 2:35 PM
What's a hem? Come to think of it, what's a curtain?

John

Andrew Ault
10-18-2005, 3:19 PM
John,

I think "Hem" is as in "hem and haw", like when I hem and haw about when I'm going to get the nightstand I'm working on completed. "Curtains" is me if I don't get it done soon.

- Andy

Lee DeRaud
10-18-2005, 3:32 PM
John,

I think "Hem" is as in "hem and haw", like when I hem and haw about when I'm going to get the nightstand I'm working on completed. "Curtains" is me if I don't get it done soon.What is this "done" you speak of? It is a concept totally unfamiliar to me...:eek:

John Bailey
10-18-2005, 3:55 PM
"Done" as in "Done for!" I am familiar with that one.

John

Dan Forman
10-18-2005, 4:02 PM
Haw Haw Haw!!!

Dan

Aaron Koehl
10-19-2005, 12:54 PM
Thanks Good Buddy.... There will be payback!

By the way Dave, I know you said that during Sue's unexpected time off she hemmed the curtains in your shop, but I don't think that I or my fellow creekers have seen pictures of them yet :)


Hahaha! That's hilarious!

Alan Turner
10-19-2005, 11:40 PM
Come on Dave, I can't help but think that, given that you are such a sensitive guy, you would truly appreciate a fine set of shop curtains. And, I find it even harder to think that you would not want to share with us a pix or two of these fine shop additions. Roger, I didn't find you edgy when when we met, but apparently you and Dave have a unique relationship. Maybe if Dave is shy, you might have a shot of these hand crafted textiles?

Byron Trantham
10-20-2005, 8:45 AM
One thing that hasn't been mentioned is how cool it is when the tablesaw blade grabs a hold of a tiny, offcut piece of wood and fires it at the ceiling where the 8 ft fluorescent fixtures live - *PINGGGG* - *CRASH*. :eek:

DAMHIKT

Kevin, I know about that problem. It's happened to me TWICE! I finally went to the Borg and bought those clear plastic sleeves that contain the glass if they break. Of course since I have installed them, about two years ago, I haven't broken another one:rolleyes:

Dave Anderson NH
10-20-2005, 12:34 PM
Since it's my turn to get ragged on I'll start another thread either tonite or tomorrow and post a picture or two of my bench room complete with curtains.:p Maybe Roger Myers and Alan Turner will be kind enough to chip in the funds necessary for me to add the finishing touches such as a nice braided rug and a Queen Anne high back padded armchair so I can comfortably read my woodworking books.:rolleyes:

Stay tuned for the next installment in this continuing saga.:D

Robert Brandt2
10-25-2008, 7:11 PM
Roger - one of the best posts I've found, but still doesn't cover my problem, so maybe you can help!

My shop is a 20 x 20 garage. No windows and unpainted sheetrock ceiling, 8' high. I have a combination of 4' and 8' flourescent lights, supplemented with incandescents mounted on tools or clamped here and there. My problem is that the average life of t8's the 4' ceiling mounted $10 fixtures seems to be 6-8 weeks. The 8' seem to last much longer. Over the past year or so I've tried leaving all the flourescents on all the time. It doesn't seem to make any difference.

I've even changed fixtures. They have all come from a big box and all have starters, not ballasts. (The last time I replaced the ballast in the 8' fixture, I decided I didn't want to do that again.) One of the 4' fixtures (that has stayed on for several years) actually melted the transformer. It almost fell out of the fixture, but by the time I discovered it, everything was cool and seemed to still be working fine - but it still burns out tubes as fast as the other units.

I'm still using "economy" grade lights, rated at 2,000 hrs. If I can't get more than several hundred from these, I don't know what a "better" light whou do, other than cost more.

What am I missing?

Thanks,
Robert

Tom Adger
10-25-2008, 7:45 PM
I cannot believe the number of post on this subject. If you want accurate color rendition, move your work out into the sunlight. Artificial lighting, no matter which kind, is not going to be the same. As far as flourescent, cool white(cw, the most common kind,) is not going to give you accurate colors. The best you can get with fluorescent, is ww(warm white), which gives you the closest approximation to incandescent lighting. even those are different. lots of luck.

JohnT Fitzgerald
10-25-2008, 8:23 PM
Who here gets power for $.08/kwH???

Peter Quadarella
10-25-2008, 9:07 PM
I have fairly new T8's in my garage and I work half in and half out of it. There is very little difference between the lighting in and outside of my garage. How someone could say that incandecents are more similar to daylight than the new flourescents is beyond me - if you stand outside and look into a room with incandecents you can see that the lighting is yellow (for contast, when you look in my garage you would think there was no roof).

There is no flicker with these new bulbs, and I never got a headache in the garage (actually due to the lower level of stress in there my headaches usually go away ;) ).

As for building in the light that the furniture will end up in - I am currently building a hall tree that will go in a sun room :). It's much easier for me to introduce an incandecent when I need it than to try to get actual colors in a room filled with them.

OK, there's my cheerleading for the new T8's. As you can tell I'm quite enamored of them ;).

John Bailey
10-25-2008, 9:32 PM
I have T-8's in my shop along with my north facing roof being clear. I use the sunlite version. I don't know if they are good or not, I just know I like them.

Oops!! Just noticed how old this thread is - I remember it now.

John

Rick Potter
10-25-2008, 9:46 PM
I am not trying to start an argument, but I would like to point out a couple things.

My current house was built in 1978, my previous house in 1973, previous to that one was 1964. ALL of them came built with built in flourescent lights in the kitchen.

Thursday, I picked up the plans from the city for my remodel.....the plans REQUIRE flourescent lights in the kitchen, bathrooms, and laundry room.....which just happen to be the next areas I am going to build nice cabinets for. No medium base bulbs allowed either, you might put other bulbs in them. I can use 'non high efficiency lighting' in the kitchen, but only half the lumens of the main area, and it must be on a separate switch, with a dimmer.

Most people around here, updating kitchens and baths, are eliminating the built in areas with flourescent tubes, but they are being replaced with flourescent can lights, not halogen.

A lighting store told me that ceiling fans with medium bulb bases are no longer made, they come with a small base socket, that only takes low watt bulbs. I got lucky, and got two of the last ones with medium bulb sockets. I put screw in flourescents in them anyway.

My entire house has flourescents, as well as the homes of my entire family. My son saved something over $100 a month on his house out in the high desert (big house, lots of kids).

As you can see, anything I build for my house will be lighted by flourescents. My new shop has six big skylights, and T-8-5000 lighting, but I have to admit that my reasoning was to save electricity, not the color of the lights.

Again...please....I am not trying to start an argument, just stating what our reality is.

Rick Potter

Bruce Page
10-25-2008, 9:58 PM
:) Wow I never knew I wasn't having fun in the shop!!

That said, I use florecents, incandesents and a hallogen lamp. I set up the hallogen lamp when I am sanding or other fine work. For the rest, the florecents work just fine.

Ditto what Jeff said. I have 32 4’ Sylvania “Sun Sticks” in my garage shop. The Sun Sticks give me ample lighting and have a CRI of about 92. I love the slight warming they give to the 5600k daylight color balance setting. I also have Halogen & incandescent lighting that I use at the workbench and on some of my machines.
The Sun Sticks cost more than the bargain borg fluorescents but the cost is offset by their long life and realistic color.

Al Navas
10-25-2008, 10:15 PM
Bruce,

Where do you buy the Sylvania Sun Sticks? I have T-8s in the shop, and have never heard of these. Now I am interested, although I am happy with the T-8s. Most have lasted well over 4 years now.



.

Ken Fitzgerald
10-25-2008, 10:27 PM
I have 44 T-8's in my shop. I also have some halogen lights on my lathe and on my drill press. The T-8s have been rock solid.

Bruce Page
10-25-2008, 10:38 PM
Al, I bought them at a local lighting store (Albuquerque Lighting) along with the fixtures but I have seen the Sun Sticks at Lowes.

D-Alan Grogg
10-26-2008, 1:07 PM
The OP is a somewhat misleading post. I've used T8's with electronic ballasts for years. I've never had headaches, BTW. And, almost every office is using fluorescent lights. To suggest throwing out all your fluorescent light in favor of halogens is a bit extreme. I have far more efficient and better lighting with my fluorescent and some individual task lights than I would if I was using halogen. If I need a "natural" light source to check appearance, then I pull out a natural light task light. It's as simple as that. Don't let the OP scare you from using common sense.

John Schreiber
10-27-2008, 10:34 AM
I always try to stay out of these lighting threads...but....
Thanks for putting your oar in here Roger. Personal impressions are valuable, but I really appreciate hearing from an expert. Facts aren't flexible and some people sometimes don't like that, but it really helps decision making for the rest of it.

I never knew the code. T=tubular, 12= 12/8ths. I always wondered.

Rob Damon
10-27-2008, 12:57 PM
Roger,

Good post. Perhaps if you do write a full article, you can address where lighting is really going....i.e. LED

They started by replacing incandescents in Exit lights, and now gradually replacing spots/downlights and are gearing up to replace the venerable 48" fluorecent lamps.

http://www.everled.com/

As an example these are available in various color temperatures, including near incandescent. Yes, they are very expensive now, but T-8's were more expensive when they first came out many years ago.

Here are some more applications:

http://www.ledwaves.com/


It may take 10 years or longer for major acceptances, but they are coming. You see their use in more and more applications. They have a much longer life and use a fraction of the energy usage.

So if you are an old dude like me, you may never see them in your shop, but some of you young-uns can certainly look forward to them.

Rob

Peter Quadarella
10-27-2008, 1:21 PM
I wouyld love some LED lights. Hopefully some day they won't cost an arm and a leg.

Chris Padilla
10-28-2008, 6:50 PM
Wow...this thread was dug up from the grave!! Still good stuff.... :)

andy Jendrzejewski
12-17-2012, 5:28 PM
I also am an artist, color is important to me on any material and I often work with fine items, drawing, carving and very precise color work. I have researched for a gallery and a workshop lighting, with color as the most important aspect to consider, as well as seeing precisely the details that a wood worker might need to see. I concluded that Solux lighting (Solux.com) is the finest light for color one can buy. They come in tracks or cans or insets. The web site has great information and test results about spectral emittance of different kinds of light and testimonials from museums that are impressive. I agree with others that you can use them only when color and point source illumination is most important and use fluorescents at other times for general tasks like sweeping the floor. We tested the lights with many different types of illumination and found that the Solux brand of bulb, was the most color balancing the warmer and cooler colors of objects (paintings) and overall gave a much richer rendition of that which was illuminated. Jamie's contention above is correct, and counters assumptions made by Jack Linsey's otherwise excellent and informative article that concentrates on fluorescents. He too suggested that one can get a balanced color temperature around where we found it balanced (3500K degrees), but he minimized the importance of CRIs (Color Rendition Index) that halogen can provide, with a comfortable amount of illumination at only 35 watts a bulb. Fluorescents don't come near the color balance across the spectrum that these halogen lights provide. It would be worth the extra study and testing to see what Jamie has proposed here.

Dan Hintz
12-17-2012, 7:37 PM
Holy resurrected threads, Batman! 7+ years old...

Jack Lemley
12-17-2012, 9:42 PM
I’ve recently been teaching in a shop which is lighted with fluorescents, and it reminds that they’re a terrible way to light a woodshop. They have two bad characteristics:


1) Bad color

I love wood. Among other things, I love it for its color. Almost all the standard cabinet woods turn weird ugly colors under fluorescents. That rich red cherry turns ugly brown, maple turns kinda green, walnut just goes flat, and the list goes on. It is just lots less fun to work with wood under that light.

In addition, any part of the job which requires color sensitivity --- for instance deciding which planks to use near each other --– is difficult to do under fluorescents. And don’t even think about stains or dyes; they often look way different under fluorescents.

(And oh by the way, the color rendering index which fluorescent manufacturers push is hogwash. While it is true that a lamp with a CRI of 92 is better than one with a CRI of 60, it is still bad. For a while, I had a shop lighted with the highest CRI lamps I could buy, but they were still a very different color from sunlight.)



2) Diffuse light

The large size of fluorescents naturally produces diffuse, even, lighting. That’s a bad thing in many woodshop operations. A point source like an incandescent is much better. Here’s some examples of where a point source is good:

Edge-gluing planks. With a point source at a nice flat angle, misalignment of the planks is easily seen by the shadow at the edge of the plank. Triming solid edgebanding is similar.
Jointing. You want to make passes on a jointer until the jointer hits everyplace along the edge. This is easy to see if you hold the plank up so that the light glances along it, and unreliable under fluorescent.
Sanding. With a point source at a low angle, it is very easy to see sanding scratches. Under a diffuse light they often escape –-- until the furniture goes into a home someplace where sunlight or a lamp exposes the mistake.


Another bad effect from diffuse lighting is that chatoyance is greatly diminished. Chatoyance really wants a light which is a point source, so that the reflection changes when you move your eye. With a diffuse light source, there’s no change when you move your eye. The result is all that beautiful curl disappears under fluorescents, and again some of the pleasure goes out of woodworking.

The better way to light a shop is halogen floods. They provide better color and chatoyance, and help you do better work.

I am very happy with my daylight T8 fixtures.

Jack

Rick Potter
12-18-2012, 1:53 AM
7 years.......that's gotta be a record.

Rick Potter

Joe Angrisani
12-18-2012, 8:52 AM
Easy on the new guy, everyone....Welcome to The Creek, Andy.

Joe Jensen
01-05-2013, 1:51 AM
Just read the whole thread, good info. I just converted nine four tube T12 fixtures to T8. I used high efficiency Sylvania ballasts and the highest efficiency Sylvania T8 bulbs. I live in AZ and my garage is air conditioned but when over 108 or so the AC has trouble keeping up. I measured the power with an RMS meter at 1920 watts and the new setup is 670 watts. It did help with the heat too. That said, I had a mix of warm and cold bulbs in T12 and liked the light better than with the high efficiency T8s which I think are 4200K. I am loving the electronic ballasts. The list price was quite high but I scored a boxof 10 on ebay for $126 delivered.

Having said all that, I've learned that the best way to judge colors is to use the light that the piece will end up in. We just remodeled a bathroom and we are using halogen bulbs in that room. I did the color matching for the dye on the walnut to the limestone under halogen lights. Nice warm walnut. In the shop it looks cool and a little blue. Outdoors it's very neutral, not warm or cool. If I used daylight bulbs in the shop I'd have ended up with something way too warm in the bath.

Lastly, I have no data to back it up, but it seems to me that the color of light changes different materials slightly differently. The stone in the bath versus outdoors has less of a color shift than the walnut. I think this has to do with the chatoyance or depth in wood grain.

thoughts?...joe