TURNING OVER A NEW
LEAF
The Leaf Volare and
Cantare digital camera backs
by John Henshall
One manufacturer has set the
benchmark for high-end professional digital cameras since
introducing the first professional studio camera at
Photokina in 1992. That company is Leaf. These days, Leaf
is one of a number of digital camera manufacturers which
use the 24 x 36 mm CCD made by Philips. So are they all
virtually the same?
Leaf Systems Inc began as an American
company, which in 1992 was acquired by the Scitex
Corporation, an Israeli-based multi-national founded in
1968 by Efi Erazi. Before Scitex, Efi Erazi worked at MIT
on the first ever digital video camera -- the one which
Neil Armstrong used to send back the first live images
from the surface of the moon. Originally known as
Scientific Technology Ltd, the first products, such as a
helicopter image stabiliser, were for military use. In
1970, the company became Scientific Textiles, Sci-Tex,
whose work included the digitisation of the Jacquard loom
and the ink jet printing of carpets. This technology lead
to Scitex producing 'Response 300', the world's first
digital pre-press system, in 1979, and the first digital
page-makeup program, the 'Vista' system -- at $350,000
including mini-computer. In 1990 Scitex acquired Iris
Graphics Inc of Bedford Massachusetts, realising that
their high quality colour ink jet printers could be used
for digital proofing. In the one thousand feet per
minute, black only, ink jet field, Scitex acquired the
Dayton Ohio facility from Kodak in 1993. These printers
have many uses, such as the printing of bank statements
and the addressing of newspapers and, in the future, they
may also be used for high-speed variable data colour
printing.
The original Leaf Digital Camera Back
(see Chip
Shop April 1993) produced 2048
x 2048 pixel images of such outstanding quality that this
camera alone confirmed the future of high quality digital
acquisition. The original DCB required three sequential
exposures, through red, green and blue filters, though a
single-shot Catchlight version followed. The current Leaf
DCB-II Live has a built-in cooling system which maintains
the CCD at 0°C. Leaf also produced a small, low cost
scanning camera, the Lumina, which had a Nikon lens
mount.
Leaf showed the Volare, the first
camera back to use the new 2048 x 3072 pixel 24 x 36 mm
FTF3020 CCD from Philips Semiconductors in Eindhoven, at
Seybold Seminars in San Francisco in August 1998. Volare
is a three-shot camera featuring the Leaf Active Cooling
System, which controls the temperature of the CCD. This
is an important feature for photographers who want the
highest picture quality, for it increases dynamic range,
helps maintain clean, noise-free images in hot studios,
and enables the use of exposure times of up to thirty two
seconds, without noticeable build-up of noise.
I visited Scitex Corporation Ltd in
Israel in May 1999, to discuss and use their forthcoming
single-shot camera back, the Leaf Cantare.
A visit to a camera manufacturer
speaks volumes about that company, even before a word is
said. Are the cameras made by the company itself, or are
they designed and manufactured outside by a third party,
reducing the company to little more than a sales and
marketing, packing and shipping organisation? What is the
after-sales back up like? Is there on-going refinement of
hardware and software?
There was no doubt on any of these
points at Scitex. Research, design, software,
manufacture, assembly, testing, packing and marketing is
all done in-house by a close-knit team. I saw it all. The
Input Systems Division, responsible for digital
photography and scanning, is run as one of a series of
autonomous internal divisions. The relaxed working
atmosphere says it all: dedicated perfection with good
humour and not a suit or tie in sight, even in the
President's office. Mind you, in Israel it's 40°C
outside. Scitex is the kind of place where you
immediately feel at ease and inspired. Even the choice of
coffee and hot chocolate flavours is studied with care.
Scitex exudes confidence and reassurance about product
continuation and backup, important if you are going to
invest in their products.
Cantare is the single-shot variant of
Volare using the striped version of the Philips 2x3K chip
-- also used in the Phase One LightPhase and MegaVision
S3 backs -- but with a big difference. The Cantare is the
only single-shot back to use active cooling of the chip.
Other manufacturers use techniques to avoid the chip
being heated (such as only powering the back during
exposure and keeping most circuitry out of the back) but
if the studio is at 35°C then the camera back will
also be at 35°C or higher. And the noise will be
four times as much as it would have been at 19°C.
This noise shows in smooth shadows and obscures fine
detail. Asked how important active cooling is, Scitex's
digital photography guru Yossi Ben-shoshan says, "It's
like baseball. You don't have to wear special shoes to
play baseball but, if you're a professional player, they
certainly help."
THE
SCITEX ADVANTAGE
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Yoav Chelouche is the President
and Chief Executive Officer of Scitex Corporation
Ltd, headquartered in Herzliya, a suburb of Tel
Aviv, Israel. He has presided over a major
turnaround in Scitex's fortunes and created a
series of autonomous internal divisions -- virtual
sub-companies which share the umbrella and
facilities of the parent company as
required.
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One of the major facilities,
shared by the autonomous Scitex divisions, is the
state-of-the-art computerised engineering
workshop.
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This on-site facility
manufactures parts for Scitex products at prices
far below those which would be paid if the work was
contracted out. Leaf uses about 10% of the capacity
of the engineering facility and could not itself
afford to have such a sophisticated workshop. Some
of the parts produced are large and of high
precision, such as this drum...
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...for the futuristically
designed Scitex Dolev image setter.
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Another section manufactures
printed circuit boards. These reels contain
thousands of microchips ...
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... which are automatically
assembled on the boards by this machine.
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MAKING
A NEW LEAF
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The man behind every Leaf camera
to date is Yossi Ben-shoshan. In 1992 he moved from
Scitex America to their new acquisition, Leaf
Systems Inc. There he was responsible for the Leaf
DCB (Digital Camera Back), first shown at Photokina
in 1992. In 1996 he took the Leaf subsidiary home
to Israel, to take advantage of in-house
manufacturing facilities and the synergy between
Leaf and the Input Systems Division in digital
imaging acquisition and color processing. Yossi
Ben-shoshan is widely regarded as one of the
world's leading experts in professional camera
design. He is also a perfectionist.
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Every Volare and Cantare board
is tested before being installed in a new
camera.
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The board is connected by ribbon
cables to a skeletal camera back containing a CCD,
mounted on a Hasselblad back.
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Testing ensures that the PCB
meets quality and functionality requirements before
being installed in a production camera
back.
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The Volare/Cantare body is a
single machined casting.
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The main board is mounted in the
back of the housing.
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The 'VH Twist' assembly, which
rotates the CCD between portrait (V) and landscape
(H) modes, fits into the front of the casting.
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One of Leaf's unique features is
its active Peltier-effect cooling of the Philips 24
x 36 mm CCD. The heat exchanger fits into the
rotator unit. It is spring loaded, to keep it in
contact with the back of the CCD. A fan removes the
heat dissipated by the heat exchanger from the
back.
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The CCD is mounted on a circular
printed circuit board. This board contains the head
amplifier and is connected to the main board by a
flexible ribbon cable.
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The CCD and board is fitted onto
the VH Twist unit...
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...which allows it to rotate
through 90 degrees. At this stage, the CCD is
protected by a cover.
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CCDs are sensitive to infra-red,
so an IR filter is mounted in front of the chip. It
must be cleaned very carefully to avoid any dust
close to the focal plane.
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A neoprene gasket seals the
space between the back of the filter and the front
of the CCD, to prevent the ingress of
dust.
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The IR filter assembly is then
fixed in position.
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The final part of the mechanical
assembly is the precision alignment of the CCD in
the focal plane using a microscope. Alignment must
be accurate in both landscape and portrait
modes.
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The microscope is first focussed
onto the backplate which interfaces with the back
of the camera. The CCD is then aligned to
this.
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Assembly and alignment
completed, the camera back is tested for
performance and to reveal any picture
blemishes.
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Finally, the backs are 'soak'
tested to ensure reliability.
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RESULT IS THE NEW LEAF CANTARE
The new
Leaf Cantare single-shot camera back mounted on
Hasselblad.
(Camera spotters tip: Instantly recognisable by the
orange VH Twist control)
OR THE
LEAF VOLARE
The original Leaf Volare three-shot camera back mounted
on Sinarcam.
(Camera spotters tip: Instantly recognisable by the
purple VH Twist control)
SHOOTING
WITH VOLARE AND CANTARE
How three-shot
and single-shot compare
Over
the past few months I have been very impressed by
single-shot camera backs using the Philips 2x3K chip,
even to the point of wondering whether a three-shot is
worth the hassle or limitations.
I therefore grasped the
opportunity to compare Volare and Cantare side-by-side on
the same subject with enthusiasm.
The two cameras share many of the same
facilities, such as Leaf VH Twist rotating the entire
chip between landscape and portrait shooting modes, CCD
cooling, software user interface, Live Focus, contrast
meter for critical focussing at a distance (shown full
size at left) and toning after shooting. A Leaf Digital
Layout facility allows an art director's layout -- or a
previous shot -- to be superimposed as an aid to accurate
composition. The Cantare has Rapid Shoot capability,
allowing successive shots to be captured every 1.3
seconds. Shots are displayed immediately on a digital
contact sheet on the computer screen. The area selected
for critical Live Focus actually moves as the lens is
focussed, tracking as changes in image magnification
during focussing move the selected area across the frame
slightly.
A collection of beer bottles provided
an effective, if somewhat unimaginative, subject for the
comparison. Foil wrapping produced some specular
highlights and fine detail close to highlight level. The
superior depth of colour and tone of the three-shot
Volare was immediately noticeable but only in direct
comparison with the single-shot Cantare. Closer
examination showed the superior resolution of three-shot.
This is hardly surprising as three exposures produce
three times as much image data as a single shot. The
black 'Quality' lettering on a red background on the
label of the right hand bottle was a particular challenge
for the Cantare. Fine black lettering on a red background
is always a problem for single-shot cameras -- try
including a Heinz baked beans tin in your test
shots.
The new Cantare, on a Hasselblad, was
crying out to be hand held and that's how I used it, for
portraits. At 20 x 13 x 9.5 cm (8 x 5 x 4 inches) and 1.3
kg (2.86 lb) it is a little on the bulky side and a good
grip would be useful. The VH Twist mechanism makes
changing between landscape and portrait modes as easy as
flicking the switch. No right-angled viewfinder is needed
for the Hasselblad. Other manufacturers' interpolation
software seems to soften the 'a' and 'b' colour channels
in Lab mode, either leaving the 'L' luminance channel or
even sharpening it somewhat. The Leaf interpolation
software I used was still in Beta form. It does not
soften the 'a' and 'b' channels but still manages
virtually to eliminate colour aliasing.
Leaf Active Cooling makes a big
difference to both backs. Switching off the cooling and
allowing the back to warm up to (air conditioned) room
temperature produced a noticeable increase in noise which
would be seen on big enlargements.
The digital
contact sheet.
So which should you buy, Volare
or Cantare? Both are state-of-the-art products, produced
by a team of perfectionists, with no compromises. Without
a doubt, the three-shot Volare produces the cleaner,
sharper images, with great colour and tonal depth and
capable of the greatest enlargement. Purists and lovers
of 4 x 5 will love its images. But it cannot capture live
subjects. The new single-shot Cantare can capture every
type of subject and, if your requirements are not for
such big enlargements, the Cantare would be a good
all-purpose choice. But if you want the very highest
quality -- better than any single shot -- you need the
Volare. You may even want to buy one of each.
Captured with
the Leaf Volare (three-shot)
Captured with
the Leaf Cantare (single-shot)
Sections
of the above shots (left) Volare (right) Cantare
displayed here at 100% (one image pixel displayed as one
screen pixel.) These sections have not been enhanced in
any way. Note the superior resolution of the three-shot
back and the lack of visible colour aliasing in the
Cantare example. At this size of enlargement, a print of
the whole image would measure over 108 x 72 cm (42 x 28
inches).
The
same sections (left) Volare (right) Cantare with Unsharp
Masking applied. Note how much better the cleaner Volare
image takes the sharpening. It also takes interpolation
better.
Further
sections of the above shots (left) Volare (right)
Cantare, displayed here at 200% (one image pixel
displayed as two screen pixels.) These sections have not
been enhanced in any way. Fine black lettering on a red
background is a particular challenge for single shot
digital cameras. At this size of enlargement, a print of
the whole image would measure over 217 x 144 cm (85 x 56
inches).
The big advantage of the Cantare is its ability to
capture action.
This section of a Cantare image is displayed at 100% (one
image pixel displayed as one screen pixel) and has not
been enhanced in any way. At this size of enlargement, a
print of the whole image would measure over 72 x 108 cm
(28 x 42 inches).
left
to right: Dennis Kaliser, Yossi Ben-shoshan, Ilan
Carmi and Shiri Brickman.
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Special
thanks to Yossi Ben-shoshan (Program Manager,
Digital Photography Products), Adina Shorr (General
Manager, Input Division), Amit Shvartz (Marketing
Director), Ilan Carmi (Product Marketing Manager),
Stanley Barkan, Dennis Kaliser, Shiri Brickman,
Laura Laloum, my long-suffering and beautiful
subject Ronit Konfidan, and Yoav
Chelouche.
For further
information about Leaf Digital Photography
see www.scitex.com/products/input/leaf/index.htm
For general
information about Scitex Corporation see
www.scitex.com
The Leaf
Volare is priced at £15,995
(US$25,000), the Cantare is £14,495
(US$23,000).
In the UK
contact Silicon Imaging Ltd at +44 (0)207 538
1010
In the US contact Sinar Bron Imaging at +1 908 754
5800
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The
editorial images for this article were photographed
in available light using a Sony DCR-TRV900
digital video camera. The still frames were
captured from the DV tape using a FireWire card and
PhotoDV
from Digital
Origin
(formerly Radius Inc.) The portrait of Yoav
Chelouche was photographed using a Nikon CoolPix
950 digital camera using an available mixture of
daylight and flourescent light. Test shots using
the Leaf Volare and Cantare digital camera backs
were made by John Henshall in Leaf's in-house test
studio in Herzliya, Israel, on 26 May
1999.
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DIGITAL
IMAGING SECRETS -- special interest
seminar
Want to
know more about Leaf's digital products and
philosophy?
Yossi
Ben-shoshan is widely regarded as one of the
world's leading experts in professional camera
design. He is one of the many designers and users
who will share their experience with you,
first-hand, at the whole-day Digital Imaging
Secrets special interest seminar at Seybold
San Francisco on Monday 30 August
1999.
Also on
this day will be the first public showing of a
fully working Nikon D1 digital
camera.
We have a
page with further information
about this special day, which is being organized by
EPIcentre's John Henshall.
Don't miss
this rare opportunity to evaluate some of the
important developments that will have a profound
effect on your imaging productivity and
profitability. We look forward to seeing you
there.
Full
information on the Seybold
San Francisco
seminars
and expo website.
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This is an
extended version of the article which first appeared as
"John Henshall's Chip Shop" in "The Photographer" magazine,
June 1999.
IMPORTANT NOTICE
This document is Copyright © 1999 John Henshall. All
rights
reserved.
This material may only be downloaded for personal
non-commercial use. Please safeguard the future of online
publishing by respecting this copyright and the rights of
all other authors of material on the Internet.
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