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1989-04-05
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~ THROUGH A SCANNER DARKLY ~
~ ~
~ How to Choose, Use and Get ~
~ The Very Best From Your Scanner ~
~ ~
~ by John Weller ~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Why buy a scanner? Why pay £100+ for a device whose sole function
is to copy from paper onto the screen? The answer used to be that you
needed a scanner to create clip art, but with the hundreds of discs of
IMG pictures now available, you could just as easily function without
one. The real reason for owning a scanner is to produce *personalised*
clip art and as a tool for creating graphics.
Serious scanner users can be divided into three main categories:
computer artists who need to input drawings and sketches, DTPers who need
to create custom clip art, and heavy text users who need to read text
from paper with an Optical Character Recognition (OCR) programme. These
categories obviously overlap in individual users, and anyone involved in
serious DTP work will use all three techniques at some time or another.
A fourth category has evolved in the last couple of years: non-
specialist users who use hand scanners to create their own clip art, and
programmers who use them as another tool for creating title and games
screens.
~~~~~~~~~~~~~~~~~~~~~~
~ CHOOSING A SCANNER ~
~~~~~~~~~~~~~~~~~~~~~~
So what's available, and at what price? A4 flatbed scanners are as
simple to use as a photocopier, but their £500+ price tag means that they
will only be considered by a serious minority of users. A slightly
cheaper solution is the Pandaal A4 Professional, a 210mm wide hand
scanner with a motor attached to feed sheets through it, but the £500
asking price severely limits its market. The third, and most cost-
effective option, is a standard 105mm wide hand scanner, of which three
are available at around the £100 mark. These are the units that I'll be
covering in this article.
Most hand scanners use the same units which are presumably produced
in the same Taiwanese factory; the differences between them are in the
interfaces used and the software supplied with them. This can vary from
the very good to the abysmal, and is the most important thing to look at
when deciding which one to buy.
The main options are the Golden Image scanner, the Pandaal Daatascan
Pro, the Zydec, and the Datel Geniscan. These are all supplied as a
scanner, an interface that plugs into the cartridge port, the software
needed to drive it, and a separate power supply unit. Each is claimed
to be capable of running in high or medium resolutions, scanning at 100,
200, 300 or 400 Dots Per Inch (DPI), and of saving the resulting picture
as either an IMG file or a Degas screen. But how do they perform in
practice? Let's have a look:
~ PANDAAL DAATASCAN PRO ~
HARDWARE: This is a pleasantly squat unit that fits nicely into either
the left or the right hand. The interface fits firmly into the cartridge
port and rests on the desktop, and the PSU is the usual 'small brick'
that can be placed out of the way under the desk. The scanner has a
small button on the left side that must be depressed when the unit is
being run over an image, and a four-position sliding switch that can be
set for line drawings or three 'dithered image' options for use when
scanning illustrations or photographs. The left side has the 100 - 400
DPI settings and a rotary switch for adjusting contrast.
SOFTWARE: Very nice indeed. The Daatascan Pro software is based on the
'page window and working window' system where you have an overall view of
the page that you're working on, plus a separate window where you can trim
and alter your current scan before pasting it onto the page. Most options
are available as either icons or menu entries.
The majority of the software's options involve setting up the
size of your work page and choosing the parameters of your current scan;
there are only a few options for trimming and manipulating the finished
scan. Most scanner settings (DPI, B/W scan or dithered image) have to be
set in the software as well as on the scanner's controls.
The software runs in high or medium resolutions, and the
finished image can be saved as either an IMG file or as a high or medium
res Degas screen. If the scanned image is larger then screen size then
you will have to choose which part of it you want to save as a Degas
screen.
EASE OF USE: Very easy to use. You choose the DPI setting on the
scanner unit, set it in the software, input the size of scan that you
wish to make (in inches or mm), and then select 'scan' as an icon or menu
option. The screen then clears and when you depress the scanner unit's
operating button and run it over the image, it appears on the screen in
real time. This means that you can alter the contrast as you're working
to produce the 'crispest' scan.
PRICE: Available from most mail-order firms for £109.99.
~ ZYDEC HAND SCANNER ~
This is a rebadged Daatascan Pro that comes with the same scanner
unit, interface, software and manual. The only difference is that it is
only available from Evesham Micros and is priced at £10 less than the
'name' version. Now you know which one to buy...
PRICE: £99.99 from Evesham Micros.
~ DATEL GENISCAN ~
HARDWARE: The scanner is more rounded than the Daatascan, but still fits
nicely into either hand. Settings available are 100, 200, 300 or 400
DPI, an operating switch, and a contrast control. The interface is much
larger than the Pandaal one and is not deep enough to be supported by the
desktop - potentially dangerous for the cartridge port. The power supply
unit appears to be very cheaply made.
SOFTWARE: Will *not* run on an STE, and Datel have "no plans to upgrade
it". That just about sums Datel up; they're good at box-shifting, but
beware if you want any technical questions answered - you'll be refered to
their resident technician, whose normal answer is, "I don't know anything
about the software; we buy that in".
The programme is the most basic that I've seen, but it does
its job reasonably well. It runs in medium or high resolutions and
scans at 100 - 400 DPI. The 300 DPI setting is almost unusable, as even
the most steady movement over the page results in extraneous vertical
lines in the scanned image. Finished scans can be saved as either IMG
files or as Degas screens. The majority of the options available are for
setting the scan itself, and the finished scan can only be rotated in 90
degrees steps or inverted in colour. You'll have to load the scan into
an art programme if you want to trim it or rotate it by a few degrees.
There's also a particularly nasty bug in the programme that
sometimes produces IMG files that won't load into most other utility, WP
or DTP programmes. The only way that I could get around this problem was
to run every IMG file produced by it through the Daatascan Pro software -
hardly an ideal solution...
EASE OF USE: Very easy to use, but with limited software options and a
really choice bug. I'd recommend this set-up *only* to anyone who's
offered it at a rock-bottom price, and is prepared to find a way around
the IMG bug.
PRICE: Currently on sale at £119.99.
~ GOLDEN IMAGE HAND SCANNER ~
See Dave Henniker's review at the end of this article.
Of the above units, the ones that I would recommend are the Zydec at
£99.99 and the Golden Image at £109.99. The Zydec offers a good range of
software functions, but the Touch-up software that comes with the Golden
Image unit is far more comprehensive and allows you to load and save in a
much larger range of formats. An upgrade has also been announced for the
Golden Image that will allow you to scan in true grey scales, rather than
mimicking them with dithering.
~~~~~~~~~~~~~~
~ RESOLUTION ~
~~~~~~~~~~~~~~
A little theory first, and then the practice... The most important
thing to understand is how the resolution that you scan and print at will
affect the size of the finished image.
Let's consider an example: you have an image that's 3" x 3" that
you want to scan. Scanning it at 100 dots per inch (DPI) will give an
on-screen image of 300 x 300 pixels: at 200 DPI, 600 x 600 pixels: at 300
DPI 900 x 900 pixels: and at 400 DPI, 1200 x 1200 pixels. Assuming that
you're working with a high resolution black and white monitor, anything
other than the 100 DPI scan will be larger than the screen size, as each
dot is represented as a pixel.
The software deals with this by allowing you to scroll through the
scan with the window bars. When you come to save the picture as an IMG
file, you'll find that the size of it is proportional to the DPI setting
that you choose. To give an example, a complex 3" x 3" image scanned at
100 DPI will give a file sized approximately 30K; a 200 DPI scan will
give 60K; a 300 DPI scan, 90K; and a 400 DPI scan, 120K.
When you print out your scan, or incorporate it into a document, you
can normally choose the DPI setting that it's to be printed at. And this
is where it gets tricky... a 3" x 3" image scanned at 100 DPI and printed
at 100 DPI will print out at 3" x 3", but any larger DPI setting will give
a proportionally *smaller* printout. Thus, a 200 DPI setting will give a
printout of 1.5" x 1.5", and a 400 DPI setting, .75" x .75". Printing at
a higher-then-scanned resolution will give a smaller printout, and
printing at a lower-than-scanned resolution will give a larger printout.
This would be fine if all WP and DTP software offered a set range of
100 to 400 DPI for printouts, but, because of the different resolutions
possible on a dot-matrix or a laser printer, you're more likely to be
offered printout resolutions of 75, 150 or 300 DPI. So, the 3" x 3"
image scanned at 100 DPI will print at 3.75" x 3.75" with 75 DPI; at 2" x
2" with 150 DPI; or at 1" x 1" with a 300 DPI setting.
The sensible thing to do is to make sure that you scan and print out
at the same DPI setting, and never go higher than the resolution possible
on your printer. For dot-matrix printers this will be a maximum of 200
DPI, and for injets or laser printers, 300 DPI.
~~~~~~~~~~~~~~~~~~~~~~~~
~ USING A HAND SCANNER ~
~~~~~~~~~~~~~~~~~~~~~~~~
The main drawback with hand scanners is that you have to move the
scanning unit as steadily as possible over the paper; any lateral
movement will give a skewed scan, which is especially noticeable in any
image with strong vertical lines. Most people overcome this problem with
practice but another way around it is to always run the edge of the
scanner along a ruler. This will give a steadier scan and will keep
lateral distortion to a minimum.
You should think very carefully before setting the area that you
want to scan. Do you want to scan the image as tightly as possible, and
keep any trimming to the minimum, or do you want to cover a larger area
and guarantee scanning all the image in one go? I normally choose the
second option as it also produces a steadier scan.
A third point to consider is whether to scan as a 'line drawing' or
a 'dithered image'. The line drawing setting applies a filter so that
any tone below the filter level will be scanned as black, and any tone
above it will be scanned as white. This is perfect for drawings or for
text, but if you want to scan photographs or any illustration with a
range of tones then you'll need the dither settings. There's normally a
choice of three of these, and each one represents grey tones by different
patterns of dots or lines. The only advice I can give you with these is
to make several scans, each with a different dither and contrast setting,
and then choose the one that you prefer.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~ CLEANING-UP and MANIPULATING SCANS ~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
You now have an image that you can print from, but a little extra
work will give you a far crisper result. Scanner software generally has
only limited editing options - enough to to edit, trim, reverse or rotate
- and the best way to remove the inevitable extraneous dots from your
scan is to load it into a good drawing programme. You can then edit it
in any way that you want to and add fills, lettering, or maybe even a box
around it.
>>>> Now go to the 'Load Picture' option and load SCANNER1.PC3 from the
Screens folder. This is a high resolution pic that won't show at its
best in colour. <<<<
The drawing programmes that I'd recommend, in order of price, are:
PUBLIC PAINTER v1.0 (an excellent P.D programme that can load and save
IMG pix, and allows you to load any GEM font without having to create a
new Assign.Sys file); Atari's HYPERPAINT 2 (an art programme that can be
run in all resolutions, and can cope with larger-than-screensize IMG
files, price £30); TOUCH UP (see Dave Henniker's review at the end of
this article); MEGAPAINT (a superb drawing and manipulation programme,
but at an £85 price); and RETOUCHE (the ultimate picture retouching
programme - more options than you'll ever need, but at a price to match).
Of these programmes, only HyperPaint 2 will allow you to work in colour
with IMG files.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~ ADVANCED and EXPERIMENTAL SCANNING ~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The emphasis so far has been on how to produce a crisp scan that can
be used as quickly as possible, but there are other techniques that can
be used if you're interested in using your scanner for creative purposes.
If you're interested in producing artwork or making backgrounds for text
to be laid onto, then you might want to deliberately distort your scan.
The easiest way to do this is to move the scanner laterally as you run it
down the page, but you could also re-scan the same area repeatedly, or
adjust the contrast to give a particularly heavy or 'washed out' image.
You could also try scanning through wrinkled cellophane, projecting
an image onto the back of a screen and then scanning the front, or
perhaps fold up the paper that an image is printed on to deliberately
break it up. (Shades of William Burrough's cut-up technique here...)
>>>> Now go to the 'Load Picture' option and select SCANNER2.PC3 from
the Screens folder. This is a high resolution pic that won't show at its
best in colour. <<<<
If you then load the image into a drawing programme you can add mono
fills, contrasting lettering or a caption at the bottom, or experiment
with pasting images together in 'replace' or 'transparent' modes. Areas
can be retouched with the spraygun, or further distorted with the options
available in the programme. The possiblities are literally only limited
by your imagination.
~~~~~~~~~~~~~~~
~ OTHER IDEAS ~
~~~~~~~~~~~~~~~
Everyone will have their own uses for a scanner, but how about
scanning your signature to use in letters, or perhaps pasting it over a
patterned background to give a 'banknote' effect? "None Genuine Without
This Trademark."
>>>> Now go to the 'Load Picture' option and select SCANNER3.PC3 from the
Screens folder. This is a high resolution pic that won't show at its best
in colour. <<<<
Programmers can use a scanner to help create title or games screens
- scan drawings in black and white and then convert them to colour.
An idea that Liz and I are working on is to create vector graphic
heraldry for a medieval Play By Mail game that we're involved with. Liz
will draw the coats of arms, I'll scan them at 200 DPI, clean them up,
and then convert them to vector graphics with either Silhouette or Avant
Vector. Voila! Graphics that can be printed at any size without loss of
detail or blockiness.
~~~~~~~~~~~~~~
~ CONCLUSION ~
~~~~~~~~~~~~~~
As you can see, there are more uses for scanners than for simply
copying an image from paper to the screen. They can be used as a
creative tool for artwork and graphic design, and as a means of freeing
your imagination if, like me, you're not particularly good at drawing.
Scan on, and Enjoy!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~ THE GOLDEN IMAGE HAND SCANNER ~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A 'hands-on' review by Dave Henniker
I have had this scanner since August of last year and have used it
fairly regularly since then. I ordered it from Evesham Micros. When it
arrived I was somewhat dismayed to find that the cartridge was a 'returned
under guarantee' job that had a previous customer's name attached. The
mains adapter had an integral European two-pin plug rather than the
normal 13 Amp type, but a shaver adapter was supplied so it could be
connected to the mains. Unfortunately, the mains adapter was duff as the
transformer primary winding was open-circuit.
Undaunted, I dug out my bench power supply and adjusted it to the
correct DC voltage, switched everything off, connected it all up and had
a go at scanning something. It worked OK but there was a shadow down one
side of every scanned image. I examined the scanner and found that the
clear plastic lens had a manufacturing defect causing the LED's light to
be defocussed.
By now I was feeling rather cynical about the "Dealer Of The Year"
award given to Evesham Micros. The package consisted of the following:
Scanner (Faulty Lens)
PSU (Two-pin plug, wobbly in shaver adaptor, designed for
220 Volts and it was duff)
Cartridge (Previous customer's name & address taped to it)
Software (TouchUp and Outprint, both OK!)
Manuals (Hardware manual - slim and distinctly Taiwanese)
(Software manual - thick and chunky, very good)
I sent the whole lot back to Evesham but kept the software and
manuals. I had plenty of time to familiarise myself with these as
Evesham's response wasn't very speedy.
TouchUp is much more than just a scanner-driver program. It can be
used as a monochrome drawing program without a scanner at all. The
drawing area can be many times larger than the screen area but is limited
by the memory capacity in your computer. There are far too many features
to go into here but the manual is very comprehensive and guides you
gently through all the options.
It requires a minimum of 1 Meg memory and GDOS (supplied) must be
installed in your auto folder. GDOS is mainly required for printing as
TouchUp doesn't actually use GDOS fonts. TouchUp has its own outline
fonts in several typefaces, and these can be scaled up as big as you like
with no loss of quality. Both TouchUp and its sister program Outprint can
act as a shell and start each other up without having to return to the
desktop.
When the faulty scanner was replaced I didn't use the supplied mains
adaptor because it had a tendency to fall out of the shaver adaptor.
Instead I used one meant for a portable TV. Don't try this yourself
unless you understand about stabilised voltages and voltages which rise
with no load. I've been using this setup for about nine months now with
no problems.
The scanner has the following controls:
START BUTTON
Right-handed users will find their thumb fits comfortably here. You
hold this in as you pull the scanner down the page.
TEXT PHOTO SWITCH
For normal black and white scans this slide switch is left in the
TEXT position. The three other positions give different dot effects
to simulate grey scales.
LIGHT DARK CONTROL
This variable control can usually be set once, then forgotten about.
You should only need to adjust it for scanning photographs or images
on dark paper.
DOTS PER INCH SWITCH
You can scan at 100, 200, 300 or 400 DPI. You have to remember to
adjust the software to the same resolution.
The scanner is really easy to use. TouchUp has options for different
lengths of scan and even half-width scans. When you select scan, the LEDs
in the scanner light up and the image underneath is visible through the
window, illuminated by the green light. When you're ready, you hold in
the Start button and move the scanner slowly across the image. You can go
as slow as you like. If you go too fast then a red LED flashes to tell
you to slow down.
A four inch wide scan at 300 DPI is 1200 dots wide. The SM124
monitor screen is 640 dots wide. If your printer can print at 300 DPI
then the printout will be the same size as the original 300 DPI scan.
However, the package may not include printer drivers for all printers.
When I upgraded to a Hewlett Packard Deskjet 500, I had to buy a new
printer driver. This was also usable with Easydraw so I didn't grudge the
extra expense too much.
Outprint is flexible and offers different scaling and justification
options. Both applications are robust and reliable (no bombs or crashes)
but are a wee bit slow. You can save and load images in a variety of
formats which makes it easy to print them on an IBM compatible with a
laser printer.
In conclusion I must say that I thoroughly recommend this package.
It gets the results I want with no hassles. The .IMG pictures are really
nice for spicing up letters in Write On.
~~~~~eof~~~~~