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We all want the best illumination with which to enjoy our epson prints!
So here is is my mini-tome and collection of links.
Part 3 of 3.
---- 10. UV Component of Full Spectrum Fluorescents: Brighteners, Fading
& Health -----
The spectral output of solar illumination (at 5000K) is fairly flat
throughout visible wavelengths, except that intensity starts to decline
at the violet edge of human vision.
The decline continues through near-UV (UVA) and Mid-UV (UVB) and reaches
zero near 300 nanometers. Far-UV (UVC) is completely filtered by the
ozone layer, and is absent from fluorescent lamps (except germicidal lamps).
Some manufacturers insist that "true" full spectrum bulbs must mimic the
UV output of solar illumination (missing UVC, appropriate levels of UVA
and UVB). Others use a looser definition of "full spectrum" in that all
(or nearly all) of the UV is filtered out by glass additives or coatings.
For epson prints, some UV output enhances the performance of optical
brighteners in the paper, which makes colors more vivid and text easier
to read. The downside is the potential for increased fading. The epson
list has had some discussion on the role of UV versus visible light in
fading. For example, R. Moyer cited Wilhelm's discovery that red light
fades (at least some types of) cyan dyes.
Philips has an interesting page on fading...
http://www.lighting.philips.com/nam/prodinfo/fluorescent/p5037_03.shtml
Some manufacturers claim health benefits of UV output. This is a known
fact for pet reptiles. Humans need UV for synthesis of the Vitamin D
series; but that is available in enriched milk. Is Vitamin D the tip of
the iceberg; are there unknown health benefits of UV? I suspect so. I do
believe that some manufactures are prematurely overstating health
benefits of UVA + UVB output (bordering on hype or even fraud). The
downside is that UVB causes cancer and sunburn. Some dermatologists
believe (given Vitamin D enriched milk) that there is no health benefit
to UV at all, only risk. I think that is hysteria. Oxygen, copper,
selenium, iron and many other nutrients are toxic at high doses but
absolutely essential in appropriate dosages; I predict that future
research will show that UVA and UVB will turn out to be the same.
Is a full spectrum better for treating seasonal depression; or is it
just a matter of intensity? Are full spectrum bulbs with UV better than
those that filter out UV? Are full spectrum bulbs with flat and
continuous spectra better than well balanced discontinuous triphosphor
bulbs (or hybrid bulbs)? Some manufacturers claim benefits for full
spectrum; most photobiologists claim that it is just a matter of
intensity. I do suffer from seasonal-independent depression. Although I
am slightly happier under Ecolume illumination, I doubt that it is
really reduces depression per se (as opposed to Paxil which really
works). I do vouch that Ecolume illumination reduces eyestrain and
related headaches and this probably accounts for most of the happy
effect, plus a placebo effect from all of my recent literature review.
---- 11. Electronic vs Magnetic Ballasts -----
Classical fluorescent ballasts are "magnetic" transformers which cycle
at 60hz. This can cause flicker, buzz, and radio interference. Newer
electronic ballasts cycle at about 20,000 Hz and do not flicker, buzz,
nor interfere with radios; they are also more efficient.
Some of the full spectrum non-compact tubes are only available as
"T-12s" and/or "T-10s" (1.5 and 1.25 inch diameter tubes) which only
work with magnetic ballasts. A few brands are also available as "T-8s"
(1 inch diameter tubes) which require electronic ballasts.
The most recent development in non-compact tubes are T-5s with matched
high efficiency electronic ballasts. For epson prints, the closest
product of interest would be the 4100K/82CR1 triphosphor Pentron from
Sylvania (but these are hard to get)...
http://www.sylvania.com/prodinfo/business/fluorescent/t5.htm
---- 12. Polarized Lighting -----
Polarizing the illumination cuts down glare (at least under some
conditions). Old style polarizing film (gray or amber stuff) absorbs too
much of the light, but there are new developments in almost-practical
polarizing technology...
http://www.mmm.com/cws/lighting.html
https://www.mmmdirect.com/mousepad/catalog.cfm
http://www.virtualdaylight.com/frames.html
http://www.polarizedlighting.com/
... I don't see how 3M polarizing sleeves for 4 foot tubes (2nd link)
could remain polarized once placed behind a diffuser, the 3rd link
interests me the most but may not be available in the USA, the 4th link
stinks of "multi-level marketing" recruitment hype.
---- 13. CRI versus other color quality measures -----
"True" color temperature ratings only apply to incadescents (including
halogens). Fluorescents with identical "correlated" color temperature
ratings may possess drastically different spectra (eg., continuous flat
vs triphosphor) and drastically different CRI ( or related) ratings.
I would have assumes that full spectrum bulbs with continuous and flat
spectra would have superior CRI ratings than discontinuous triphosphors
or hybrids, but this is not necessarily true, as can be seen with the
comparison between a "full spectrum" Philips Colortone 50 versus a
"hybrid" Philips 950...
http://www.lighting.philips.com/nam/prodinfo/fluorescent/p5037_02.shtml
... but at least the C50 beats the triphosphor Ultralume 50. This page
also discuses the limitations of "CRI" as a measure for illumination quality.
More on light quality and the human visual system, including limitations
of the "lumen" and "foot-candle" units of intensity...
http://www.taiowa.com/dtbsof.htm
http://www.soluxtli.com/edu13.htm
---- 14. more compact fluorescents: intro & integral -----
Compacts which screw into regular incadescent sockets may be either
"integral", in which case the fluorescent tube and adapter ballast are
fused into a single unit, or "modular", in which the tube plugs into a
separable adapter ballast. The integral or modular adapter may be either
a magnetic or electronic ballast. A fifth option are fixtures into which
a compact is plugged in; some of the previously listed aquarium lighting
links offer some exotic examples of these. I'm only going to cover
compact screw ins with integral or modular electronic adapters, with
color temperatures above 2700K.
I don't have spectra for any compacts.
Vita-Lite Spiralux 5500K/9xCRI (I assume that their spectra are similar
to other Vita-Lites; these are too expensive)...
http://www.taiowa.com/dtsp1.htm
http://jademountain.com/compactfluorescents.html
Verilux 6500K/85CRI integral compacts (full spectrum, triphosphor,
hybrid???; these are too expensive)...
http://www.ergolight.com/products8.html
Philips 17W 5000K (?) integral compact that I saw at Home Depot (white
color looks nice in store, but too expensive per lumen)...
http://www.I-can't-find-at-Philips-website.com/
Let me repeat the Lumiram Ecolumes which I have tried and loved
("3500K", no spectra)...
http://www.lumiram.com/html/LRBEcolu.html
http://store.yahoo.com/comfort/comfluorligb.html
5000K/85CRI integral compacts, 23W & 26W (price per lumen is good, I'll
get a couple)...
http://www.fullspectrumsolutions.com/Fluorescent.htm
USPAR 4100K/80CRI integral compacts (price per lumen is good, CRI quoted
from personal communication with USPAR, probably a triphosphor)...
http://www.colehardware.com/hotline/99/02/ecosaver.htm
5000K/84CRI Sun-A-Lite integral compacts (way too expensive!)...
http://www.sunalite.com/s_lightbulbs.html
http://jademountain.com/compactfluorescents.html
5000K/82CRI Ott integral compacts (way too expensive, possibly available
at Home Depot)...
http://www.ottbiolight.com/Compact.htm
Triten 50 Compacts (way too expensive locally, second link stinks of
multi-level marketing scheme)...
5000K/88CRI Panasonic triphosphor (or hybrid?) integral compacts...
http://www.panasonic.com/MHCC/pl/capsu.htm
http://www.panasonic.com/MHCC/pl/technoi.htm
http://www.efficienthome.com/index2.htm
6500K integral compacts (CRI not listed, electronic vs magnetic adapter
not listed)...
http://www.amazinglightbulbs.com/fullspectrum.html
4100K & 6500K (82CRI?) Mitor integral compact fluorescents
http://www.mitor.com/catalog/mtl20f.html
3000K (82CRI?) Sylvania integral compact fluorescents (is the color
temperature too close to the ugly 2700K compacts???)...
http://www.sylvania.com/prodinfo/business/fluorescent/swdxel.htm
http://www.sylvania.com/prodinfo/business/fluorescent/specs.htm
A truly novel 3000K/82CRI GE "Genura" integral compact "fluorescent" (is
the color temperature too close to the ugly 2700K compacts???)...
http://www.gespectrum.com/inet/business/products/genura.htm
http://www.gespectrum.com/inet/business/products/genurab.htm
---- 15. more compact fluorescents: modular -----
3500K/82CRI modular GE 2D lamps...
http://www.gespectrum.com/inet/business/products/2d.htm
http://www.gespectrum.com/inet/business/products/2db.htm
Screwin electronic ballast adapters for plugin compacts...
http://www.mitor.com/catalog/mpcen26-32tf.html
http://www.mitor.com/catalog/mpcen26-32tb.html
http://www.mitor.com/catalog/mpcen42tf.html
http://www.mitor.com/catalog/mpcen42tb.html
http://store.yahoo.com/springlamp/modsprin.html
http://store.yahoo.com/springlamp/elbalad4pins1.html
http://store.yahoo.com/springlamp/elbalad4pins.html
4100K/84CRI and 5000K/88CRI Panasonic plugin fluorescent tubes...
http://www.panasonic.com/MHCC/pl/compac.htm
3500, 4100 & 6500K (all 82CRI) Mitor plugin fluorescent tubes...
http://www.mitor.com/catalog/mte18f.html
http://www.mitor.com/catalog/mte18b.html
3500 & 4100 (all 82CRI) GE & Sylvania plugin fluorescent tubes...
http://www.gespectrum.com/inet/business/products/biax.htm
http://www.gespectrum.com/inet/business/products/biaxb.htm
http://www.sylvania.com/prodinfo/business/fluorescent/dultein.htm
http://www.sylvania.com/prodinfo/business/fluorescent/specs.htm
---- 16. Added in proof -----
Yet another Vita-Lite spectrum ("doctored" but not "deceptive")...
http://www.taiowa.com/dtguide.htm
GE ecolux 3500 & 4100K at 86CRI T8 specs (no spectra, probably
triphosphor or hybrid)...
http://www.gespectrum.com/inet/business/products/ecoluxb.htm
http://www.gespectrum.com/inet/business/quality.htm
-- Ben Haskell
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