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Don Klipstein Don Klipstein is offline
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Default Florescent Tube Lights which to buy?? Hello??

In article , bud-- wrote:
Crackles McFarly wrote:
Maybe the server lost this post on some other servers.
Here is my question again....


Your first post made it. Not obvious what you are doing and what the
problem is from your post.

Lumens=1200 on first 2 lights I bought and they were really dim.
LOWES,HOME DEPOT I couldn't find one higher than 1250 Lumens?

I decided to pick one based on CRI. The higher number was suppose to
be the most bright...

I picked two lights that had LOWER Lumens but HIGHER CRI.

Did I make the right choice, if NO please tell me how to identify
these.


CRI is color rendering index and indicates how the lamp compares to
natural light (not an exact definition). 100 is maximum. If the light
was very green the CRI would be low. CRI measures color 'quality'.

Brightness is measured by Lumens.


The color can match that of daylight or of sunlight or of incandescent
light and the color rendering index can still be anywhere as high as 100
or abysmal, depending on what the spectrum looks like.

Even knowing both CRI and color temperature won't tell the whole story.
For example, upper-grade-triphosphor fluorescents (with CRI in the range
of 82-86) tend to have most of their color distortions in the direction of
colors being "brighter and more vivid than proper", although reds can
appear orangish.
Most non-triphosphor fluorescents (that is, most fluorescents with CRI
above 86 or below 82) have their color distortions mostly in the direction
of "darker and duller than proper". Of course, the distortions should be
minimal if CRI is above 90.

Another thing: Light output is usually compromised if CRI is above 86
or color temperature is above about 4300-5000 K or so.

Keep in mind that there are a few different color rendering indices, and
it appears to me that the usaul one is Ra8 - which only tests 8 colors.
Another tests 14 or 15 (I forget for now). As a result, CRI as used now
only roughly indicates color rendition accuracy.

- Don Klipstein )