Part 1 of 3
I recently finished a draft of a chapter for John Barnier's book, COMING INTO
FOCUS. It will be a multi-author book on methods for alternative
photographic processes and will be published next year. Several list members
are also contributing chapters to this book. There have been recent questions
on the list about digital photography, and the list appears is moving a bit
slowly. So, I thought I would send the manuscript to the list. I am sending
it in three parts, as my EMail server chokes on files larger than 20KB. I
welcome comments and questions from all of you. Some of this material I
posted to the list last year; hope the veterans don't mind a little
repetition.
Since 1989, I have confined my work in photography to platinum and palladium
(Pt/Pd) printing. In 1994, I began using digital methods exclusively to make
negatives for contact printing. You can adapt the methods I describe here to
any process which uses black and white (B&W) negatives for contact printing.
I will explain the advantages of digital methods for alternative photographic
processes, hardware and software requirements, the steps involved in making a
digital B&W print, and methods to adapt digital output devices to the needs
of the B&W photographer. This is not intended as a comprehensive
step-by-step guide for adapting digital methods to alternative photographic
processes. In this relatively short piece, I can give only a brief overview
of the subject; and, there are several important areas, such as monitor
calibration and sharpening techniques, which I will not discuss. Instead, I
will concentrate on the areas that have presented the biggest challenges to
me and will emphasize problems which are peculiar to black and white
photography and contact-printing processes.
Adobe PhotoShop is the industry standard for photographic software and is
used by virtually everyone involved in digital photography. You will need
some familiarity with PhotoShop and with basic concepts of digital image
processing; any of the dozens of books on PhotoShop will help you in getting
an overview of these issues.
WHY USE DIGITAL TECHNIQUES FOR ALTERNATIVE PROCESSES?
Digital methods offer you several advantages for alternative printing
processes. One of the most obvious benefits is the ease with which you can
enlarge negatives. You can make digital B&W negatives with an imagesetter
(described below) in any size up to about 20"x24". The conventional
techniques for negative enlargement (direct-positive film vs. enlarged film
interpositive and new negative) are at best difficult and present several
problems; these include dusts spots, loss of information involved in
translation through two generations of analog film images, and difficulty in
precisely controlling the contrast and density range of the final negative.
In my case, before converting to digital techniques I used an 8"x10" camera
to get 8"x10" negatives, as the nuisance of using a large camera for me was
preferable to the difficulties involved in enlarging smaller negatives. I
now use a 6x7 cm. SLR for original negatives, as negative enlargement is a
trivial problem with the computer.
With digital methods, you can tailor the density and D/LogE curve of the
negative to the needs and peculiarities of any B&W printing method. For
example, the characteristic curve of Pt/Pd has a long, gently sloping toe and
shoulder. Because of this, it is often difficult to obtain good separation
of tones in both shadows and highlights. With digital negatives, I can
compensate for this by specifically steepening the extremities of the D/LogE
curve in the final negative. I can also precisely specify the DMin and DMax
of the negative, so that the negative is very easy to print, with the
shortest possible exposure times.
Even if you have no interest radically altering images in ways that are
obviously "computerized," digital methods give you extraordinary control over
the photograph in ways that far surpass traditional darkroom techniques for
negative and print manipulation. You can burn and dodge at the
pixel-by-pixel level and optimize contrast and density for individual areas
of the image. Negatives which I had filed away as unprintable because of
technical problems such as excessive contrast, dust on the film, and uneven
development became easy to print once I had converted to digital methodology.
WHAT ARE THE STEPS INVOLVED IN MAKING AN ALTERNATIVE PROCESS PRINT
WITH DIGITAL METHODS?
Digital image processing can be divided into three phases: input, image
manipulation, and output.
INPUT: Digital cameras with resolution comparable even to 35mm film are
still prohibitively expensive. So, most photographers using digital
techniques still rely on conventional film for capturing the original image.
Once you have the image on film, it must be scanned to produce a digital
file which the computer can use. You can either scan the film yourself with a
personal desktop scanner or have it done for you at a service bureau.
IMAGE MANIPULATION: I will say little about the actual process of
manipulating the image in the computer. With PhotoShop, there are virtually
no limits to what you can do with a photographic image.
OUTPUT: Once you've finished manipulating the image on your computer screen,
you must translate that image into a B&W negative for contact printing.
This translation is the biggest obstacle in applying digital methods to
alternative photographic processes. Most B&W photographers doing digital work
use an imagesetter at a service bureau to create their digital negatives.
Other output devices include desktop laser and inkjet printers, ordinary
computer monitors, and film recorders.
SERVICE BUREAUS:
A service bureau is a shop filled with very expensive hardware, including
scanners, imagesetters, film recorders, and other professional input and
output equipment. It is geared to the needs of the color printing trade;
their staff often know little about the needs of the B&W photography, to say
nothing of the requirements of alternative processes.
If you do much work in digital B&W photography, you will use a service bureau
to make your final digital negatives and possibly also to do your scans. The
service bureau is in a difficult position in dealing with B&W negatives for
alternative processes. You will be asking for custom work which will require
considerable effort from their personnel to help you adapt their machinery
for alternative process work. However, the bureau must get work through the
shop as fast as possible, as it has to cover the cost of a million dollars
worth of hardware which is depreciating to a very small value at an alarming
rate.
It has been my experience that unless you know exactly what you want or you
have a sympathetic friend working in the shop, scans and B&W negatives from
service bureaus are often less than satisfactory. At least in your initial
forays into the digital world, you will probably be better off using one of
the handful of bureaus which have done a lot of work with B&W photographers.
I can recommend Command-P in San Antonio, Texas (634 West Sunset, San
Antonio, Texas 78216). Command-P has several years' experience in B&W
digital photography and worked with Dan Burkholder to develop the methods
described in his book (Making Digital Negatives for Contact Printing; Bladed
Iris Press; 7003 Forest Meadow; San Antonio TX 78240; bladediris@aol.com).
HARDWARE REQUIREMENTS:
The price of computer hardware drops almost daily. Three years ago, a
personal computer system adequate for digital B&W work cost about $10,000.
Now, that price has dropped more than 50%. Here is a brief summary of a
system which would be adequate for beginning to work in this area. There are
several items to be considered in a computer system for digital imaging:
1. Operating system
2. Random access memory (RAM) and hard drive
3. Monitors
4. Transportable media
5. Scanner
6. Digitizing pad
MACINTOSH O.S. OR WINDOWS: Your first decision will be to choose between the
Macintosh OS and Microsoft Windows. The Macintosh remains the industry
standard for graphics work and has an operating system that is somewhat
easier to use than Windows. However, all the software you will need is
available on Windows systems, and most service bureaus now will accept either
Macintosh or Windows files. In either case, you will need a machine with one
of the latest microprocessors: the PowerPC chip for the Macintosh OS, or the
Pentium for a Windows system.
For digital imaging, the Macintosh OS offers two major advantages over
Windows. First, it supports the simultaneous use of two monitors. On my
Macintosh, I have a 15" color monitor and a 20" grayscale monitor. I keep
all the PhotoShop menus open on the smaller monitor, leaving the entire 20"
screen for the image I'm working on.
Second, despite the claims of "Plug and Play" compatibility with the newer
Windows computers, it is easier to install and use external peripheral
devices on a Macintosh system. This is not a small consideration, because
the home digital imaging system usually has several external devices
(scanner, printer, hard drive with transportable media, tape or disk drive to
back up the primary hard drive, digitizing pad, etc.).
RANDOM ACCESS MEMORY (R.A.M.): PhotoShop uses enormous amounts of RAM. In
addition to the memory needed to run your operating system and PhotoShop, you
will need at least 400 KB of RAM per square inch of final image size in B&W
work. So, for example, you will need a **minimum** of 40 MB of RAM if your
final image size is 8"x10" (at least 8MB for the OS and PhotoShop; 32 MB for
the image). The more RAM you have, the faster your system will run.
I have found that 40MB is not quite enough RAM for an 8"x10" image if you
are simultaneously working with more that two Layers in PhotoShop; 64MB (or
more!) is better.
HARD DISK: You will need a large hard drive, as digital image files are
huge: a file for a single 8"x10" B&W image can range in size from 7 to 30
MB. I would consider a 2 gigabyte hard disk as the minimum; 3 or 4 GB is
better.
COMPUTER MONITORS: The situation with monitors is as with RAM and hard
disks: larger is better. If your graphics work is limited to B&W images,
consider a 20" or 21" grayscale monitor. Grayscale monitors are much sharper
than color monitors of similar size, as they have only a single electron gun
rather than three and there is no loss of sharpness due to imperfect
convergence. They are also much cheaper than comparable color displays. A
20" grayscale monitor costs about $700, versus about $2,000 for a good 20" or
21" color unit.
TRANSPORTABLE MEDIA: To send your files to a service bureau, you will need
some sort of transportable media. Most workers use a removable hard disk,
such as a SyQuest, Zip, or Jaz drive. Before purchasing a drive, check with
the service bureau you'll be using to see what removable media they accept.
The price on transportable media has dropped considerably; for example, a
Zip drive now costs about $130.
SCANNER: Finally, you should consider purchasing a scanner rather than
having a service bureau do your scans for you. As I'll discuss later, good
scans are a critical part of the digital imaging process, and sooner or later
you'll want to have direct control of the scanning process. A scanner
adequate for B&W photographic work costs about $1,500.
DIGITIZING PAD: The mouse is the tool you'll use for guiding the cursor over
the image in PhotoShop. If you do a lot of work in PhotoShop, you should
consider buying a digitizing pad, in which the mouse is replaced by a
pencil-like stylus. The stylus has a more natural feel than the mouse for
drawing on the computer screen. Pads range in cost from $150 to $500,
depending on the size of the pad surface.
A final note about hardware costs: If you have extra money to spend, put it
into additional RAM and a larger monitor. There is no such thing as a
PhotoShop system with too much RAM, and a large monitor will make all aspects
of image editing easier and more pleasant. RAM is now quite inexpensive
(about $190 for 32MB).
SOFTWARE:
While there are other products on the market, PhotoShop remains the industry
standard and is the benchmark by which all other image-processing software is
compared. It can be criticized for minor shortcomings; but, it is an
extraordinary program and will do anything you could conceivably want in your
alternative process work.
SCANNING:
The importance of a good scan cannot be overestimated. There is an art to
making a good scan, and it has the same importance as having a perfect
in-camera negative for traditional printing methods. If you have a service
bureau do custom scans for you, it will not be cheap. It has been my
experience that service bureau personnel do an excellent job with color scans
(that is, after all, their main business) but know little about the technical
requirements of B&W scans. If you know someone at your service bureau and
can work side-by-side with the scanner operator as he or she makes your
scans, you can get good results. If not, your scans will probably be
mediocre and often unacceptable.
Sooner or later, you will probably want to buy a scanner. Obviously, most of
us cannot afford a $100,000 drum scanner like that used by the service
bureaus. So, the problem becomes to adapt a more inexpensive scanner ($1,500
is what it takes) to your requirements.
You will need scans which will provide about 300 pixels per inch (PPI)
resolution at your final negative size. So, the resolution requirement for a
scanner is dependent on the size of your original negative. For 35mm film,
you will need a scanner which can resolve about 2500 to 3000 PPI in order to
get a final image size of 8"x10". For a an 8"x10" image from a 6x6 cm
negative, the scanner must resolve about 1400 PPI. A 4"x5" negative
requires 600 PPI resolution, while an 8"x10" negative needs only 300 PPI.
Because of this wide range in required resolutions, the choice of a scanner
for personal use is dependent on the size of your original negative. The
choices and methods for 35mm and large format negatives are relatively
straightforward. Medium format negatives present some problems.
If your work is limited to 35mm, you can buy a good desktop scanner for under
$1,500. You should realize, however, that 35mm scanners cannot be adapted to
scan any larger film sizes. The output of these scanners is good enough for
a final image size of no larger than 8"x10".
For larger film sizes, you will need a flatbed scanner with a transparency
adapter. For about $1,500, you can get a scanner which has an optical
resolution of 600 PPI, has 30 or 36 bit color, and will accept transparencies
(positive or negative) up to 8"x10". Pay no attention to advertising claims
about interpolated resolutions: interpolation gives empty magnification, and
the only number that matters is the actual optical resolution.
I have a Microtek Scanmaker III flatbed scanner, which has worked well for my
large format negatives. At 600 PPI, it will scan my 4"x5" negatives for a
final image size of 8"x10"; I can achieve a final image size of 16"x20" with
my 8"x10" negatives.
End of Part 1