Fluorescent lights; is 3100K too "warm"?

[Greg L. Brown]

I'm setting up my shop lighting and I need some advice on the "color temperature" of the fluorescent tubes. There are lots of choices, ranging from: 3000K - "Soft White" to 4100K - "Cool White" to 5000K+ "Natural Sunshine / Daylight."

I'm very much leaning towards the softer end of the spectrum, because I don't like the "bright white" industrial look of "Cool White." I like the natural yellow tint from incandescent lights.

I found 4' Phillips fluorescent tubes (maybe they were GE; can't remember) at Home Depot that are 85 CRI (color rendering) and 3100K color temperature. The chap at Home Depot talked me into the 3100K tubes because he said they would look great in a woodshop. He said he worked at Phillips for 10 years, so I assume he know what he was talking about. My other choices were higher "temps," say 5000K+, but the CRI was still 85. So I'm not loosing CRI by sticking with the 3100K "temp." I think 3100K will look nice and "warm" in a woodshop.

What do you guys think about 3100K for a color temp? Anyone using ~3000K fluorescent tubes in their shop? Any complaints? I was really impressed I could get 3100K and still get a 85CRI.

This is related to my post about general layout and number of fixtures, which I received many helpful replies: http://www.sawmillcreek.org/showthread.php?t=93901

Thanks,
Greg

[David G Baker]

In many cases color temperature is a personal preference. I personally like the higher color temperature light sources closer to 6400 degrees Kelvin is more to my liking. Over 90% of my household lighting is in the 5500-6500 degrees Kelvin and I love it. My shop on the other hand is the old T12 buzzers that are on my long list waiting for a change.
Once you get adjusted to the higher color temp it is hard to go back to the old yellow look. If the lower color temp lighting is bright enough I don't have any problem with it.

[Don Abele]

Greg, the information below is a cut and paste from this thread: http://www.sawmillcreek.org/showthread.php?t=86674 which was talking about lights for photography. This information may help you though.


Here's a graphic I found a while ago that always helped me with color temps:

http://www.sawmillcreek.org/attachment.php?attachmentid=90970&thumb=1&d=1213835475 (http://www.sawmillcreek.org/attachment.php?attachmentid=90970&d=1213835475)

If you notice, daylight is about 5500K, so a bulb at 6500K will have a bluish tone to it. The higher the number the cooler (bluer) the tone. Lower numbers are said to be warmer. I typically use CFL's at 5000K and find they are the most neutral in tone.

Be well,

Doc

[Denny Rice]

I'm setting up my shop lighting and I need some advice on the "color temperature" of the fluorescent tubes. There are lots of choices, ranging from: 3000K - "Soft White" to 4100K - "Cool White" to 5000K+ "Natural Sunshine / Daylight."

I'm very much leaning towards the softer end of the spectrum, because I don't like the "bright white" industrial look of "Cool White." I like the natural yellow tint from incandescent lights.

I found 4' Phillips fluorescent tubes (maybe they were GE; can't remember) at Home Depot that are 85 CRI (color rendering) and 3100K color temperature. The chap at Home Depot talked me into the 3100K tubes because he said they would look great in a woodshop. He said he worked at Phillips for 10 years, so I assume he know what he was talking about. My other choices were higher "temps," say 5000K+, but the CRI was still 85. So I'm not loosing CRI by sticking with the 3100K "temp." I think 3100K will look nice and "warm" in a woodshop.

What do you guys think about 3100K for a color temp? Anyone using ~3000K fluorescent tubes in their shop? Any complaints? I was really impressed I could get 3100K and still get a 85CRI.

This is related to my post about general layout and number of fixtures, which I received many helpful replies: http://www.sawmillcreek.org/showthread.php?t=93901

Thanks,
Greg

Greg if you want a light with a "warm" color you need something in the 3000K range. The closest thing to natrual daylight lighting is 5500K bulbs-these bulbs are used in the photography industry and can be expensive, a lot of photography color labs use these lights to judge print color, tone, and if prints need to be adjusted in any way, i.e :too much blue in a print,ect. The further you go past 5500K in a bulb the "cooler" the bulb will be (or more blue) things will look.

[Jim Becker]

Personally, I also prefer towards the upper end of the spectrum for lighting. While it's a little harsher at first, it doesn't tend to skew colors as much and that's important for the finishing process. You can always thrown in a few incandescents (which I have) when you want it warmer and turn them off when you need true color presentation.

[glenn bradley]

I run 5100 to 5500 (can't recall exactly) I believe it is GE's eco cool white. T-8's, electronic ballast. As Jim says, they are a little harsh at first but not as bad as "daylight" (6500k+) that make you look blue.

I find the 5000k range gets me the most light with the least lamps while keeping a neutral environment. I have other lamps and incandescents that I use if I am trying to color a finish for a specific environment. For general shop I like the 5000k+ lamps.

[Wilbur Pan]

One thing I've never understood about the "use higher color temps for better color rendition" thing is that the odds are that whatever piece you are working on is going to wind up under incandescent, or more likely these days, "soft white" compact fluorescent bulbs, which have a color temp in the 3000°K range, so if you have 5000°K bulbs in your shop, your workpiece won't look the same in your shop as it will in its intended destination.

The other thing to keep in mind is that the CRI is a different thing than the color temp of your lights. You can have bulbs of different temperatures with the same CRI, at least if you believe the manufacturer's specs.

If you like higher color temp bulbs because you like working in that light, that's another thing entirely.

[Chris Friesen]

The other thing to keep in mind is that the CRI is a different thing than the color temp of your lights. You can have bulbs of different temperatures with the same CRI, at least if you believe the manufacturer's specs.

That's correct. The CRI compares colour rendering to an ideal blackbody at the specified temperature. Incandescent light by definition has a CRI of 100. The best fluorescents have a CRI of 98 (Philips TL950) but they're expensive. CRI of 85-90 can be had reasonably, while your basic "cool white" has a CRI in the 60s.

I use 5000K bulbs with a CRI of 86. Looks great.

[Don Bullock]

Greg, in my current garage I have a mixture of both 3200 (designated for kitchen & bath) and 5000. I did this as an experiment for the shop I'm having built at our new house. While to some it may look strange I like the effect. I, however, will be going to the 5000 range for the new shop. They put out a lot more light and are closer to daylight than the "warmer" tubes. I also used my bathrooms as part of the experiment. In one bathroom I have the 3200 kitchen & bath tubes the 5000 in the other. I have to admit that the 5000 are much better for the bathroom than the 3200. Disclaimer -- The tubes I'm using are GE from the BORG. They may be different from tubes from other sources. I don't know what the CRI of them is.

[John Bush]

Hi Greg,
I use 5500K in my Dental operatories because it provides the most natural light range for choosing porcelain crown shades. I had tried a variety of other temps and the 5500's seem to be the best. As you can imagine, the extra tubes end up in my shop and I haven't missed a shade yet!!

[Peter Quadarella]

I feel more awake and seem to have an easier time focusing on detail with the cooler lights. I go cool in bathrooms, my kitchen and my shop - living room, dining room and other spaces which are less functional get warmer lights.

[Larry Conely]

In the printing industry where neutral color perception is critical, 5600 Kelvin is the standard. I believe this evolved from the color temperature of photographic film. Personally, I like warmer light. I think you should use whatever pleases you.

[David G Baker]

At one time I printed color portraits and could not believe the different color customers wanted. Most wanted the warmer colors but it would vary from peach to almost robin's egg blue. I would let them choose from proofs rather than finish an order and have it rejected.

[glenn bradley]

As Chris stated; most of my stuff ends up under incandescent lamps in living rooms, dining rooms and bedrooms. They rarely end up under regular shop lights or business office "blue" tubes. I picked the lamps that gave me the closest to "light-bulb-100-CRI" look that I could find for my finishing area.

With my semi-gloss painted walls and open rafter ceiling, a random group of victims I pulled into the shop to compare picked Sylvania Cool White Plus model 24400 (Lowe's part number 132452) for the non-electronic T-12 tubes as the close to incandescent winner. For the easy-on-the-eyes lamps over tools and the bench I run electronic ballast fixtures with GE F32T8-SP65-ECO lamps.

[Chris Padilla]

I think the borg had 4 different color temps for the T8s I picked up. I bought them all and evenly mixed them in throughout all my fixtures. I dunno...works fine for me.

[Don Abele]

I think the borg had 4 different color temps for the T8s I picked up. I bought them all and evenly mixed them in throughout all my fixtures. I dunno...works fine for me.

Chris, the real question though is how do THE curtains look under that cornucopia of colored tubes??? :p

Be well,

Doc

[Chris Padilla]

Good grief!! THE curtains are long, long, LONG gone!! They didn't survive one washing! :D