fluorescent lights

I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.


--
RIch

On 19/09/2012 20:30, RichD wrote:
I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

Depends what you are photographing but you can get standard filters that
roughly correct fluorescent light to approximately daylight.

Mostly the problem comes from too much green so digitally a tweak of the
green channel and auto white balance will get you something like.

--
Regards,
Martin Brown

On Wed, 19 Sep 2012 12:30:51 -0700 (PDT), RichD
wrote:

I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

The problem is that no specific light spectra are associated with all
fluorescent lamps. They vary from make to make: many manufacurers
offer several different types and they all can suffer from changes as
they age. See http://en.wikipedia.org/wiki/Fluorescent_lamp

"Color rendering index (CRI) is a measure of how well colors can be
perceived using light from a source, relative to light from a
reference source such as daylight or a blackbody of the same color
temperature. By definition, an incandescent lamp has a CRI of 100.
Real-life fluorescent tubes achieve CRIs of anywhere from 50 to 99.
Fluorescent lamps with low CRI have phosphors that emit too little
red light. Skin appears less pink, and hence "unhealthy" compared
with incandescent lighting. Colored objects appear muted. For
example, a low CRI 6800 K halophosphate tube (an extreme example)
will make reds appear dull red or even brown. Since the eye is
relatively less efficient at detecting red light, an improvement in
color rendering index, with increased energy in the red part of the
spectrum, may reduce the overall luminous efficacy.[19]

Lighting arrangements use fluorescent tubes in an assortment of
tints of white. Sometimes[weasel words] this is because of the lack
of appreciation for the difference or importance of differing tube
types.[citation needed] Mixing tube types within fittings can
improve the color reproduction of lower quality tubes.

Depending on your camera, you may get fairly close to a good
adjustment. Otherwise you have to deal with it in post processing.

It can't be too difficult. You are not the first person to be faced
with this problem. :-)
--

Regards,

Eric Stevens

Eric Stevens wrote:
On Wed, 19 Sep 2012 12:30:51 -0700 (PDT), RichD
wrote:

I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

The problem is that no specific light spectra are associated with all
fluorescent lamps. They vary from make to make: many manufacurers
offer several different types and they all can suffer from changes as
they age. See http://en.wikipedia.org/wiki/Fluorescent_lamp

"Color rendering index (CRI) is a measure of how well colors can be
perceived using light from a source, relative to light from a
reference source such as daylight or a blackbody of the same color
temperature. By definition, an incandescent lamp has a CRI of 100.
Real-life fluorescent tubes achieve CRIs of anywhere from 50 to 99.
Fluorescent lamps with low CRI have phosphors that emit too little
red light. Skin appears less pink, and hence "unhealthy" compared
with incandescent lighting. Colored objects appear muted. For
example, a low CRI 6800 K halophosphate tube (an extreme example)
will make reds appear dull red or even brown. Since the eye is
relatively less efficient at detecting red light, an improvement in
color rendering index, with increased energy in the red part of the
spectrum, may reduce the overall luminous efficacy.[19]

Lighting arrangements use fluorescent tubes in an assortment of
tints of white. Sometimes[weasel words] this is because of the lack
of appreciation for the difference or importance of differing tube
types.[citation needed] Mixing tube types within fittings can
improve the color reproduction of lower quality tubes.

Depending on your camera, you may get fairly close to a good
adjustment. Otherwise you have to deal with it in post processing.

It can't be too difficult. You are not the first person to be faced
with this problem. :-)

Hi,

Some cameras have built-in fluorescent tube correction factors that can
be turned on. Take test pix with the various correction factors, then
see which please you.

Mort Linder

On 2012.09.19 15:30 , RichD wrote:
I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

Read the manual for your camera where it pertains to White Balance.

And/or Consider adding appropriate magenta filters to your lens
(shooting "daylight" WB). If you're using magenta _and_ flash (for
fill), then the appropriate green filter needs to be added to the flash.

If you shoot raw you can also correct later when importing into
photoshop (or other editors). But if shooting only JPG, then WB or
magenta filters are the way to go.

--
"C'mon boys, you're not laying pipe!".
-John Keating.

On 2012-09-19 14:25:23 -0700, Mort said:

Eric Stevens wrote:
On Wed, 19 Sep 2012 12:30:51 -0700 (PDT), RichD
wrote:

I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

The problem is that no specific light spectra are associated with all
fluorescent lamps. They vary from make to make: many manufacurers
offer several different types and they all can suffer from changes as
they age. See http://en.wikipedia.org/wiki/Fluorescent_lamp

"Color rendering index (CRI) is a measure of how well colors can be
perceived using light from a source, relative to light from a
reference source such as daylight or a blackbody of the same color
temperature. By definition, an incandescent lamp has a CRI of 100.
Real-life fluorescent tubes achieve CRIs of anywhere from 50 to 99.
Fluorescent lamps with low CRI have phosphors that emit too little
red light. Skin appears less pink, and hence "unhealthy" compared
with incandescent lighting. Colored objects appear muted. For
example, a low CRI 6800 K halophosphate tube (an extreme example)
will make reds appear dull red or even brown. Since the eye is
relatively less efficient at detecting red light, an improvement in
color rendering index, with increased energy in the red part of the
spectrum, may reduce the overall luminous efficacy.[19]

Lighting arrangements use fluorescent tubes in an assortment of
tints of white. Sometimes[weasel words] this is because of the lack
of appreciation for the difference or importance of differing tube
types.[citation needed] Mixing tube types within fittings can
improve the color reproduction of lower quality tubes.

Depending on your camera, you may get fairly close to a good
adjustment. Otherwise you have to deal with it in post processing.

It can't be too difficult. You are not the first person to be faced
with this problem. :-)

Hi,

Some cameras have built-in fluorescent tube correction factors that can
be turned on. Take test pix with the various correction factors, then
see which please you.

Mort Linder

Better; Shoot RAW. Adjust WB temperature and tint/hue in ACR.

Best; Shoot a RAW calibration/reference shot with a WhiBal card under
the Fluorescent light. Set WB in ACR.
http://michaeltapesdesign.com/whibal.html
Take a look at some of the videos.

Compromise #1; If you must shoot JPEG set WB to Fluorescent.
Compromise #2; Use a WhiBal card. It will help, but not as much as
shooting RAW.



--
Regards,

Savageduck

RichD writes:

I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

Some modern cameras have seven different "fluorescent" white-balance
presets. But if color is important, then I *strongly* suggest you just
set a custom white-balance. That will take care of the cases where the
lights in use don't exactly match any of your presets, and will do about
the best possible with the case where the lights don't actually all give
out the same color (different brands of bulbs and such).

Also, shoot raw, so you can sort it out later if you absolutely have
to. But doing a white balance in the camera is going to help in that
situation, so do that even if you're shooting raw.
--
Googleproofaddress(account:dd-b provider:dd-b domain:net)
Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/
Photos: http://dd-b.net/photography/gallery/
Dragaera: http://dragaera.info

On 9/19/12 2:30 PM, in article
, "RichD"
wrote:

I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.


--
RIch

You really gotta watch out for 'raccoon eyes" with overhead flu sources as
well as CB. I would suggest using an 18% grey card to get started.

On 9/19/12 4:46 PM, in article
, "Alan Browne"
wrote:

On 2012.09.19 15:30 , RichD wrote:
I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

Read the manual for your camera where it pertains to White Balance.

And/or Consider adding appropriate magenta filters to your lens
(shooting "daylight" WB). If you're using magenta _and_ flash (for
fill), then the appropriate green filter needs to be added to the flash.

If you shoot raw you can also correct later when importing into
photoshop (or other editors). But if shooting only JPG, then WB or
magenta filters are the way to go.

There ARE gels for Cool White and other types of flu bulbs available from a
pro camera store or theatrical supply house, BTW. Use those to cover your
fill flash source.

On 9/19/12 4:52 PM, in article
2012091914524850878-savageduck1@REMOVESPAMmecom, "Savageduck"
wrote:

On 2012-09-19 14:25:23 -0700, Mort said:

Eric Stevens wrote:
On Wed, 19 Sep 2012 12:30:51 -0700 (PDT), RichD
wrote:

I have to do some camera work under indoor
fluorescent light. It's bright, no flash needed,
but I'd like to know what adjustments to
ameliorate color distortion.

The problem is that no specific light spectra are associated with all
fluorescent lamps. They vary from make to make: many manufacurers
offer several different types and they all can suffer from changes as
they age. See http://en.wikipedia.org/wiki/Fluorescent_lamp

"Color rendering index (CRI) is a measure of how well colors can be
perceived using light from a source, relative to light from a
reference source such as daylight or a blackbody of the same color
temperature. By definition, an incandescent lamp has a CRI of 100.
Real-life fluorescent tubes achieve CRIs of anywhere from 50 to 99.
Fluorescent lamps with low CRI have phosphors that emit too little
red light. Skin appears less pink, and hence "unhealthy" compared
with incandescent lighting. Colored objects appear muted. For
example, a low CRI 6800 K halophosphate tube (an extreme example)
will make reds appear dull red or even brown. Since the eye is
relatively less efficient at detecting red light, an improvement in
color rendering index, with increased energy in the red part of the
spectrum, may reduce the overall luminous efficacy.[19]

Lighting arrangements use fluorescent tubes in an assortment of
tints of white. Sometimes[weasel words] this is because of the lack
of appreciation for the difference or importance of differing tube
types.[citation needed] Mixing tube types within fittings can
improve the color reproduction of lower quality tubes.

Depending on your camera, you may get fairly close to a good
adjustment. Otherwise you have to deal with it in post processing.

It can't be too difficult. You are not the first person to be faced
with this problem. :-)

Hi,

Some cameras have built-in fluorescent tube correction factors that can
be turned on. Take test pix with the various correction factors, then
see which please you.

Mort Linder

Better; Shoot RAW. Adjust WB temperature and tint/hue in ACR.

Best; Shoot a RAW calibration/reference shot with a WhiBal card under
the Fluorescent light. Set WB in ACR.
http://michaeltapesdesign.com/whibal.html
Take a look at some of the videos.

Compromise #1; If you must shoot JPEG set WB to Fluorescent.
Compromise #2; Use a WhiBal card. It will help, but not as much as
shooting RAW.


True that. Good info, Duck!