[Coral-List] color balance in underwater photos

Larry Gatz larry at larrygatz.com
Mon Sep 8 15:08:39 EDT 2003

Above water color balance is assured by placing an 18% Gray Card (Readily
available from Kodak) in the scene, making an exposure and then correcting
the image file in Photoshop...simply apply an over all correction to bring
the Gray Card into correct balance.  The standard is easily read using the
eyedropper tool available within Photoshop.

Under water I would suggest obtaining a water proof gray standard and
include it in the scene.  This could be as simple as painting a sheet of
plastic to carry along under water and placing it near the subject...to be
cropped out of the final image file. A known color standard is all that is
needed and gray is the normal color.  You could use any solid color.

Sounds like you have already amassed images that you now wish to "correct".
In that case, with no known standard, you can apply what you consider
"correct"...(IE. X amount of Red)...make an action in Photoshop and apply to
all your images. The problem here is that the same amount of correction
might be too much or not enough for some images. The correction will vary
depending on depth, surface lighting conditions, water surface conditions,
distance of your UW lighting source from subject, film type, film emulsion,
accuracy of exposure, lens manufacturer, etc.  Obviously, there are more
than just a few qualities to control here.

Larry Gatz

Miami/Ft. Lauderdale

Larry Gatz captures directed, spontaneous moments of life for advertising
and promotional imagery.

Online Portfolios:  www.larrygatzphotography.com,
www.photoserve.com/portfolio/gatz_larry and now

-----Original Message-----
From: Burnside, Jeff (NBC, WTVJ) [mailto:Jeff.Burnside at nbc.com]
Sent: Monday, September 08, 2003 10:00 AM
To: 'larry at larrygatz.com'
Subject: Larry: Want to take a crack at Question 1?

This is a global listserv for coral experts.

If you have time, email your answer to coral-list at coral.aoml.noaa.gov

Jeff Burnside

-----Original Message-----
From: coral-list-request at coral.aoml.noaa.gov
[mailto:coral-list-request at coral.aoml.noaa.gov]
Sent: Sunday, September 07, 2003 12:00 PM
To: coral-list at coral.aoml.noaa.gov
Subject: Coral-List Digest, Vol 3, Issue 5

Send Coral-List mailing list submissions to
	coral-list at coral.aoml.noaa.gov

To subscribe or unsubscribe via the World Wide Web, visit
or, via email, send a message with subject or body 'help' to
	coral-list-request at coral.aoml.noaa.gov

You can reach the person managing the list at
	coral-list-owner at coral.aoml.noaa.gov

When replying, please edit your Subject line so it is more specific
than "Re: Contents of Coral-List digest..."

Today's Topics:

   1. color balance in underwater photos (Ivor D Williams)
   2. question regarding importation of red coral to the USA
      (Anne Cohen)


Message: 1
Date: Fri, 05 Sep 2003 10:18:10 -1000
From: Ivor D Williams <ivor at hawaii.edu>
Subject: [Coral-List] color balance in underwater photos
To: coral-list at coral.aoml.noaa.gov
Message-ID: <7991f7afff.7afff7991f at hawaii.edu>
Content-Type: text/plain; charset=us-ascii

I'd very much appreciate some advice on applying color balance
correction to underwater photos - in our case taken in very clear
Hawaiian water at 40' deep. There seem to be a number of programs
which can handle that kind of thing (iCorrect, Color Pilot) and
presumably it can be done with Photoshop. Some informed advice on
which of methods work best (especially whether one of them can correct
multiple images as a batch job) and what specific adjustments we
should make, would be a great help.



Dr Ivor D Williams
Honokohau Marina
74-381 Kealakehe Pkwy, Suite L
Kailua-Kona, HI 96740
(808) 327 6231 office
(808) 987 4154 cell


Message: 2
Date: Sat, 06 Sep 2003 10:38:16 -0700
From: Anne Cohen <acohen at whoi.edu>
Subject: [Coral-List] question regarding importation of red coral to
	the USA
To: coral-list at coral.aoml.noaa.gov
Message-ID: <3F5A1B87.24997324 at whoi.edu>
Content-Type: text/plain; charset=us-ascii

Dear All
A jewellery supplier in Massachussetts contacted me regarding a shipment
of "synthetic" red coral they received from Thailand, that was
subsequently held but not confiscated by US Fish and Wildlife who issued
the supplier with a "Notification of Wildlife Importation/Exportation
Violation". Apparently USFW had tested the items and found them to be
real coral.

The jewellery supplier is anxious to learn more and avoid illegal
importations. I'd appreciate your comments and answers to these specific
questions that were addressed to me:

If it is "real" coral is all coral considered endangered and banned
from Importation into the U.S., or O.K. to import with a license? We
have taken much time to research this, but the information  on coral is
vast. It seems there are thousands of types of coral. Some perhaps more
endangered than others? Is there any difference when importing "live"
coral as compared to "dead" coral. It seems coral is very easy to
purchase, both live (as for fish tanks) and the type for
ornamentation/jewelry. How can that be if it cannot be legally imported
into the U.S.? Is coral cultivated in certain countries for re-sale?

Many Thanks


Coral-List mailing list
Coral-List at coral.aoml.noaa.gov

End of Coral-List Digest, Vol 3, Issue 5

More information about the Coral-List mailing list