North Carolina State Historic Preservation Office
DIGITAL
PHOTOGRAPHY
FOR
HISTORIC PROPERTY SURVEYS and NATIONAL
REGISTER NOMINATIONS
A Guide for HPO Staff, Survey
Consultants, and Nomination Preparers
POLICY AND GUIDELINES
Revised November 2008
Note: The State Historic
Preservation Office (HPO)
requires the use of digital photography for all grant-funded survey and
National Register nomination projects. While the HPO prefers and
encourages the
use of digital photography for all survey and National Register
projects,
regardless of the funding source, the HPO will continue to accept,
process, and
print traditional black and white film as long as we are able to equip
and
maintain a darkroom. We will also continue to accept color slides for
presentations (which we will scan), though we no longer process slide
film
in-house.
See the companion document,
Working with
Digital Photographs, for an overview of digital
photography and a review of free or inexpensive software packages for
managing
and editing digital photographs.
Going Digital: Digital photography offers speed,
flexibility, and cost savings in acquiring, editing, sharing,
presenting, and
printing photographs. It enables use of a single camera to obtain
photos for
every step in the process of recording, presenting, and nominating a
property
or district. But it also introduces a number of image management
challenges
that are quite different from those of dealing with film negatives and
prints.
All HPO professional staff are required to learn how to use
the office digital cameras; to scan printed materials and slides; to
manage
digital image files on their computers and in the digital image library
on the
server; to edit digital images with Photoshop Elements; to create
presentations
with PowerPoint; to burn photographs and presentations to CD; and to
use the
office digital projector.
Consultants wishing to move to digital photography should be
willing and able to:
1. Acquire
and learn to use a good quality digital camera.
2. Learn to
copy image files from the camera’s memory card to your computer and
organize,
copy, rename, selectively delete, back up, and otherwise manage the
image
files.
3. Acquire
and learn the basics of photo editing software to manipulate images and
achieve
optimum quality and size, which will vary depending on the end-use of
the
image. This means you will have two versions of some images -- one for
prints
and another for presentations and attachments to email. At the least,
you
should be able to copy an image, resize an image, rotate and crop an
image, and
perform basic enhancement functions with brightness and contrast
controls.
4. Acquire a writable CD drive (now
standard on
most computers) and burn files to a CD.
5. Learn to
create presentations with PowerPoint or similar software for use in
public
meetings. The day may be coming when it is the only means of making
presentations unless you are able to take your own slide projector.
Contents of This Policy:
I. General
Requirements
II. Digital Images for Historic
Property Surveys
III. Digital Images for National
Register Nominations
I. General
Requirements
Camera
Equipment:
While neither the HPO nor NPS
specifies particular brands, models, or minimum cost of an acceptable
digital
camera, a camera should have at least
3 megapixels with good
optics.
Most cameras on the market today have at least 5 megapixels. But the
size in
megapixels alone does not determine photo quality, which is also
dependent on
the lens, the size and type of the camera's sensor, and other factors.
Prices for higher quality SLR digital cameras have been
dropping and now approach the cost of SLR film cameras. Some allow you
to
interchange the lenses from your SLR film camera. The HPO recommends
the use of
SLR digital cameras, but they are not required. However,
the
HPO reserves the right to refuse photos that we believe are not of
acceptable quality.
Image File Formats
Most
digital
cameras by default create images
in a format called
jpeg (identified by the extension .jpg at
the end of
the filename, and pronounced JAY-peg). This is the standard for
day-to-day
digital photography and is acceptible for general survey work and for
National Register nominations provided the images meet the minimum size
standards. See
Working with Digital Photographs
for more information about file formats.
Minimum Image Size
The minimum image
dimensions for both surveys and National Register nominations is 1950
pixels
x 1350 pixels. They may of course be larger. (See Working
with
Digital Photographs for an explanation of image size, print
size, and
resolution). Such an image would make a
print of 6.5" x 4.5" at a
resolution of 300 ppi (a 7” x 5” print with margins). A 3
megapixel
camera should create an image of about 2100 x 1400 pixels, and this is
why it
is the minimum for survey and National Register work. We will not
quibble
over minor variations in pixel dimensions.
Submission
of Images:
Burning Images to CDs:
Digital photographs should be submitted on CDs. Do not use
"rewriteable" CD-RW disks, which often cannot be read by computers
other than the one on which they were created. Use the less expensive
CD-R
disks. Photos that are burned to the CD cannot subsequently be edited
on the
CD, though you can add additional photos or copy over a photo with a
new
version of the same file name at a later time. The XP operating system
enables
you to burn files to a CD without the purchase of any special software.
Emailing Images to the HPO: Because of the large file
size of digital photographs taken straight out of a camera and the
limitations
of our email storage,
we can accept high
resolution photographs as attachments to email only in special
circumstances
when there are only a few and you have prearranged their submission.
One or two reduced size images (200 KB or less) sent for informational
purposes
– as in “Have you ever seen anything like this?” – are OK to email at
any time.
See
Working
with Digital Photographs
for information about reducing the size of an image for email and
presentations.
II. Digital
Images for Historic Property Surveys
An Important Reminder: Survey
photos are always a
component of a National Register nomination project. Nomination
preparers
utilizing digital photography should be thoroughly familiar with this
section
of the HPO digital photography policy.
Advantages of Digital
Photography in Surveys: A
digital camera offers several advantages in historic property surveys:
The surveyor may see and make proofs
or prints of pictures the same day they are taken, avoiding the long
wait of having proofs and negatives returned from the lab.
There is no expenditure for film, whether black and white or
color slides. While there is some expense for ink and paper for making
proofs, it is much less than the cost of proofs made from negatives on
photographic paper.
If the camera has a large enough memory card, the surveyor
may shoot pictures all day or longer without having to stop to load
film or replace the card. (Keep that battery charged, and keep a
backup battery!)
One camera provides the images needed for survey record
photographs, National Register nominations, and public presentations,
eliminating the need to carry two cameras or to switch film types while
shooting pictures.
On the other hand, digital photography
requires additional
responsibilities on the part of the surveyor:
Selecting Survey Photographs:
The surveyor is
responsible for selecting images to be included with the property file.
Most
people have the tendency to take more digital photos than film photos,
because
it is so easy and seems “free.”
Duplicate
images and images of poor quality should be deleted, if not from
the
surveyor’s copies of his or her original images straight from the
camera, then
from the images selected for the survey file, printed on proof sheets,
and
burned to a CD.
Naming Survey Photographs:
The
surveyor is responsible for naming the
image files.
Important Notes:
1)
For survey and nomination
projects, you must
obtain survey site numbers from the HPO before naming your photographs.
2)
It is
permissible to abbreviate property name and address as long as the name
and
address are readily apparent.
Conventions for Naming Survey
Photographs:
Rural Properties
County AbbreviationSiteNumber_PropertyName_month
and year_Photographer’s initials-Photo Number.
Thus for the Johnson Farm, site CH
457 in
Chatham
County, the name
becomes
CH457_JohnsonFarm_6-07_pbs-01.jpg
Using -01, -02, etc. instead of -1,
-2, etc. will keep your renamed photos in the order in which you named
them in
an alphabetical list. Otherwise they will be listed as -1, --10, -11,
-12, ...-2,
-20, -21, and so forth.
Do not use
letters instead of numbers to distinguish the individual photographs.
Certain photo management programs
do not automatically insert the hyphen. In place of the hyphen, an
underscore
or a blank space is permissible.
Do
not include information in the image file name about the view
depicted
in the photo.
If no family name is associated
with a property, you may use a generic building type like "House" or
"Store" etc. If a generic building type is used in place of a family
name, it must be followed by the road number or the 911 address. Thus:
CH765_House_SR1243_6-07_pbs-01.jpg
or
CH765_House_8788WhiteMtnRd_6-07_pbs-01.jpg
Urban Properties
Also include the town name.
County AbbreviationSiteNumber_Town_PropertyName[OR
PropertyAddress]_month and year_Photographer’s initials-Photo Number.
Example:
CH670_SilerCity_HarrisBuilding_10-07_crb-01.jpg.
For urban properties that don't
have a common name or regularly used historic name, use the street
address. Thus:
CH671_SilerCity_423NMainSt_10-07_crb-01.jpg.
Do
not include the historic district name, if any.
Using software for
batch renaming multiple photos at one time. See
the companion document,
Working with Digital Photographs,
for a review of free or inexpensive software you can use to rename
large
numbers of photographs with one operation.
Even without batch renaming software, you can use the computer’s
memory
to capture all the information except the photo number at the end, and
paste in
everything except the final number for each image. This is often the
quickest
way to rename a small number of photos for a single property.
Editing Survey
Photographs: The surveyor may undertake basic editing of images
before
printing proofs, including rotating, cropping, or enhancing
brightness/contrast
as needed. However, the original pixel dimensions of the images
(allowing for
some cropping) should not be changed.
The
images should not be
converted from color to grayscale. Black and white proofs and
prints
can be made from the color images. See
Working
with Digital Photographs
for a review of software for editing images.
Proof Sheets for Survey
Files: Proof sheets of
digital photos are required. They provide the same function as
traditional
proof sheets from film to enable users to review survey files and
nominations.
The surveyor has two options for proof sheets:
1. Print the
proof sheets yourself on a home or office printer.
2. Submit a CD
(with the photos named as described above) to the HPO for printing of
proof
sheets for a fee. This process is similar to submitting film for proof
sheets,
and with equivalent costs. The HPO photography services fee schedule is
posted
at -------- If the HPO prints the proof
sheets, all of the photos for a particular property must be in its own
folder.
Printing proof sheets at home:
Proofs
may be printed on a typical home
printer, whether laser or inkjet, and may be in color or black and
white
(again, do not convert images from color to
grayscale) on a premium quality, bright white paper (24 lb weight
or higher)
or low-cost photo paper to reduce costs as long
as the images are
crisp and
legible. There should be a minimum of 4 and a maximum of 9
images per
8 ½ x 11 sheet, with no image smaller than 3 inches on its
longest side.
Labeling proof sheets: This may be done by hand in
the traditional way with one label per proof sheet written on the front
or back
of the sheet. Proofs should be labeled with property survey site
number, name, location,
photographer (initials are acceptable), and date (month and year). For
urban properties
, the location is the
town; if an urban property has only a generic
name such as “commercial building,” rather than a historic name, the
street
address must also be included. For
rural
properties identified only by a generic name, the road number or 911
address
must be indicated. If a rural property has a family name, no location
information is needed.
Views also must be
indicated, either on the front below the image or on the back,
lined up
with the image.
Several software packages can print proof sheets with the
file name under each image and add a title line for the entire sheet
(i.e., the
block of information traditionally written on the back of black and
white proof
sheets). See the companion document,
Working
with Digital Photographs, for a review of free or
inexpensive software
that can create labeled proof sheets.
The only thing you may need to write on the
proof sheets is specific information about views.
Burning
CDs of Survey Photographs: Use a CD-R, not a CD-RW. For a survey
project,
the photographs of multiple properties may be burned to a CD – as many
as it
will hold.
Do not make a
separate CD for each individual property. If you have
already created a separate folder for each property because you earlier
submitted a CD to the HPO photo lab for printing of enlarged proofs,
you may
leave the photo files in the folders. Otherwise, do not create a
separate
folder for each property on the CD. Label each CD with county, project
name,
photographer, and date created. Protect CDs in a plastic case or heavy
paper
sleeve.
III. Digital
Images for National Register Nominations
Photographs for a
National Register nomination are a
subset
of the photos you have made in the survey phase of your work with a
property or
district.
Your selected National
Register photos for submittal to the National Park Service should be
included
among those named and proofed as described above in Section II.
Even if you make additional visits to a
property or district to take photographs specifically for the
nomination,
you
should first name and proof the photographs as
described for survey photographs. Your National Register
photographs
are
copies of your original survey
photographs that are given new names and other special treatment to be
included
with the nomination. Remember that the minimum image dimensions for
both
surveys and National Register nominations is
1950 pixels x 1350
pixels.
Selecting and Copying
Photos for the Nomination: Select
the photos you want to include with the nomination, just as you would
select
appropriate views from proof sheets printed from film. Create a
separate folder
on your computer to which to copy those photos selected for this
specific
nomination. (The survey photos remain in a
separate folder.)
Note: Consult with HPO
National Register
staff in
Raleigh
about
photo selection for the nomination prior to submitting your photo order.
Editing NR Photographs:
If you are able to work
with an image editor such as Photoshop or
Photoshop Elements, you may straighten, crop, improve brightness and
contrast,
etc., while maintaining the resolution created by your camera.
Do not convert the images to grayscale.
Except for any minor cropping that may be needed,
do not
reduce the pixel dimensions of your photographs as created by
your camera.
Naming
NR Photographs:
Name the image files for a National Register nomination as follows:
For an individual property,
for example the Johnson Farm in Chatham County:
NC_ChathamCounty_JohnsonFarm1.jpg
-- where 1 is the photo number.
For a historic district:
NC_NewHanoverCounty_SunsetParkHD25.jpg
-- where 25 is the 25th photo included in the
nomination and
keyed to the map.
Notes:
1)
Do not use
letters to identify photos in a sequence; only use numbers.
2)
The word
“County” must be spelled out.
NPS digital photo policy (
http://www.nps.gov/history/nr/policyexpansion.htm)
also allows use of the district inventory number for properties within
nominated
districts, but we no longer use inventory numbers in district
nominations in
North Carolina.
Thus the
example shown above meets NR requirements.
Image format: NPS requires
that digital photographs be
submitted on
a CD in the TIF format. Images in the TIF format are more stable than
the jpeg
format, but require many times as much disk space. There are two
options for
converting your images to the TIF format:
1. The HPO will
convert your JPEG pictures to the TIF format and burn them to the CD to
submit
to NPS for a fee.
2. If you have image editing software that
can
convert JPEGs to TIFs, you may do the conversion yourself if you are
comfortable with the process and only if
you also are printing the photographs (see below).
Burning the NR CD: Burn the
selected images as
JPEGs, properly named, to a CD-R. Limit nomination photographs to a
single
nomination per disk (whether property or district), even if you are
submitting
two or more nominations at the same time. Identify the CD with county,
property
or district name, date created, and your name.
Submitting the NR CD:
There are two options for
submitting the NR CD to the HPO:
1.
Send
your CD to the HPO Raleigh reviewer, along with an order form for
prints (
PDF version;
Word version) The
reviewer will
forward your
order to the HPO photography clerk.
2.
If
you have converted the images to uncompressed TIFs and made the prints
yourself, send a CD with the TIFs to the
Raleigh
reviewer along with your prints.
Note: All
HPO printing of digital photographs for NR nominations is done by the
HPO’s
Raleigh
photo lab (not in the field offices).
Nomination Prints: The HPO
has a printer with
inks and paper that meet NPS archival standards and will print
nomination
photographs being submitted to the National Register. We will also burn
a CD
with the final TIF images to submit to NPS with the nomination. The
photography
clerk will send the prints to you for labeling as in the past and will
bill you
for the cost of the prints and creation of the CD for NPS.
If you do your own printing, you must verify in writing that you
have met the federal guidelines regarding the ink and paper used in the
production of the prints. See
NPS
digital photo policy (
http://www.nps.gov/history/nr/policyexpansion.htm).
VERY IMPORTANT: The nomination photo number sequence written
on the back of the photos must match the number sequence of the digital
file names. For example, for the Johnson Farm nomination, the print
labeled # 1 should be NC_ChathamCounty_JohnsonFarm1.jpg. The
print labeled #2 should be NC_ChathamCounty_JohnsonFarm2.jpg, and so
on. If you want your first photo to be the “glamour
shot,” it should be NC_ChathamCounty_JohnsonFarm1.jpg.
Fee
Schedule for Nomination Prints and CDs: As of August
2006, we no
longer require 8x10 prints for nominations, regardless of whether the
photo
source is film or digital.
5x7 prints:
$4.00 each; three sets will be printed for nominations
8x10 prints (when
requested by client; not required for nominations): $5.00
Burning the TIF CD
for NPS: $2.00
Shipping and
handling fee: $2.00
Click here for the complete
HPO photography services fee schedule.
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