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Old December 1st 04, 10:26 PM
Alan Browne
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RSD99 wrote:

"... Reveal lamps have a color temperature
of approximately 2850 degrees Kelvin and a CRI of 75."

Does **not** sound good for use with Daylight balanced color film, or
Daylight white balance.

(1) The color temperature is very **low** ... standard photofloods are 3200
/ 3400 degrees Kelvin ... and they require substantial filtering to match
the daylight standard of 5500 degrees Kelvin.

(2) A "CRI" of 75 is very low for any photographic application. You should
be looking at something with a "CRI" in the 90%-plus range.


1) Don't top post.
2) Read the thread ... I was answering somebody else.

A: It's hard to read
Q: Why?
A: No
Q: Should I top post?











"Alan Browne" wrote in message
...

Viken Karaguesian wrote:

Hi all,

I've been wondering about these GE "Reveal" light bulbs. Can they be


used

indoors for photography or are they not correctly color balanced? Until


now,

I've been using an 81A (blue) filter when taking indoor pictures and
daylight balabced film.

Anyone know what color temp the lightbulbs are?

What happens if you use flash with these bulbs?

Thanks in advance for any replies.


From GE (by e-mail):

"Similar to other common household bulbs, Reveal products use
incandescent lamp technology. The quality of the Reveal light
is achieved by adding the element Neodymium to the glass. It
is what gives GE Reveal bulbs their distinctive powder-blue color
when not lit. When lit, the element provides a pure, true light
by filtering out much of the dulling yellow cast common from
ordinary light bulbs. Reveal lamps have a color temperature
of approximately 2850 degrees Kelvin and a CRI of 75."

2850K sounds pretty close to a regular incandescent bulb, so you might


not see

much difference at all (or the GE lady replying doesn't know what she's


talking

about). The CRI indicates a decent ability to light things in a manner


that

'reflects' (PNI) their true color under natural light.


http://www.google.ca/search?num=20&h...q=define :col
or+rendering+index

has many general defs of CRI that are not terribly coherent.

As they say, "go buy a couple and test it" (use a neutral slide film like


Sensia

100 or EliteChrome 100).

Cheers,
Alan


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-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: there's no such thing as a FreeLunch.