FAQs
Here are some Frequently Asked Questions. If you have a specific question
that is not addressed in this section, please contact
Technical Support.
Q: What is meant by flat size or press sheet?
Q: What is meant by trimmed size?
Q: What is meant by finished size?
Q: What is a PMS (spot) colour?
Q: What is a colour separation?
Q: What is the difference between four colour process and spot colour printing?
Q: What is meant by resolution?
Q: What resolution should my photographic images be?
Q: What is a vector graphic as opposed to a bitmapped graphic?
Q: What are the preferred formats for graphic images and photos in jobs to be submitted to Samco?
Q: What native application programs does Samco support for full colour printing?
Q: How do I write a Postscript file (or print to disk)?
Q: Do you accept Mac or PC files?
Q: Are there any guidelines I should follow when I submit a job to you on disk?
Q: What is meant by weight of paper?
Q: Why does
it cost much more per unit to print
small quantities than it does to print larger
quantities?
A: Printing costs are based on materials and labour. Offset printing requires
the making of film and plates, setting up the press for the particular
image, ink colour, size and type of paper being printed and washing up
the press to make-ready for the next job. To print additional images while
the press is set up for your custom job is only a matter of a small amount
of press time and additional paper. Print-on-demand or digital printing
has brought the cost of short-run printing down by eliminating the cost
of film and plates, and reducing set-up times, although some set-up charges
such as filehandling still apply.
Q: What is
meant by flat size
or press sheet?
A: Flat size refers to the size of a printed sheet including bindery marks,
colour bars, crop marks and bleeds.
Q: What
is meant by trimmed size?
A: Trimmed size refers to the size of a piece after it has been cut to
size (as opposed to an uncut press sheet with bindery marks, colour bars,
crop marks and bleeds).
Q: What
is meant by finished size?
A: Finished size refers to the size of a printed piece after all bindery
processes have been applied, such as trimming, die-cutting, folding and
binding.
Q: What is
a crop mark?
A: A crop mark is a line printed outside the finished size of a piece
that shows where the piece is to be cut to size.
Q: What is a
bleed?
A: A bleed is any image that extends beyond the trim size of a printed
piece. A bleed is necessary on any image that extends to the edge of the
trimmed sheet, since it is impossible to cut precisely on the edge of
an image. The industry standard for a bleed is to extend the image 0.125"
beyond the trim edge.
Q: What is
a PMS (spot) colour?
A: A PMS colour is a colour that is printed in an ink mixed according
to the Pantone Matching System, which is a system of mixing colours by
weight, using a standardized set of basic ink colours. This system is
the international standard by which almost all printers mix their colours.
Pantone colours are used in spot colour printing as opposed to four colour
process.
Q: What
is the difference between four colour
process and spot
colour printing?
A: Spot colours are custom mixed colours commonly used in one, two and
three colour printing where reproduction of colour photos is not required.
Four colour process refers to the process whereby all colours are broken
down into four ink colours: cyan, magenta, yellow and black (CMYK, respectively).
These four colours combined in various intensities are capable of reproducing
colours found in photos and other full colour images.
Q: What is
a colour separation?
A: A colour separation is any image carrier such as a film negative, paper
positive, or digital channel breaking a piece into its individual colours
(either process or spot) that is a component of multi-colour printing.
When combined, the colour separations create a colour composite of the
finished piece.
Q:
What is digital printing?
A: Digital printing refers to methods of printing in which the images
are transferred directly to the printer without the use of physical image
carriers such as film or plates. There are many different methods of digitally
reproducing an image, some examples being toner devices using the xerographic
method (much like photocopiers), computer-to-plate (where the image is
created on a printing plate by a computer driven laser and the plate subsequently
mounted on a press) and direct to press (where the image is created by
a computer driven laser onto plates already mounted on a press) The latter
process is used by Samco on its Heidelberg DI, resulting in high quality
offset printing with the speed and economics of digital printing.
Q: What
is offset printing?
A: Offset printing is the printing method whereby ink is applied to a
resist-type printing plate where the desired image is ink receptive. This
image is then transferred to a rubber "blanket" that allows
the image to transfer to a wide variety of paper substrates. This is by
far the most common printing method for high quality printing.
Q: What is
a halftone?
A: A halftone is a photographic image broken down into varying densities
of dots. This allows a printing device to reproduce a wide range of tones
while printing in a single colour. By combining halftone images in the
four primary printing colours (cyan, magenta, yellow and black) a full
colour image can be reproduced.
Q: What is
a duotone?
A: A duotone is a two-colour halftone reproduction from a one-colour photograph.
Q: What is meant
by LPI?
A: LPI stands for lines per inch. This is a measure of halftone screen
frequency, or the number of columns or rows of dots per inch in a halftone
image. The optimum screen frequency for a halftone image varies from device
to device, with most desktop laser printers having an optimum screen frequency
of 60 lpi and offset presses using 133 to 175 lpi.
Q: What
is meant by resolution?
A: Resolution can be broken down into two categories: image resolution
and printer resolution. These are two entirely different measurements.
Image resolution refers to the pixel size of an image. In graphic arts
terminology, image resolution refers to the number of pixels per inch
in an image at the size it is to be reproduced. Printer resolution refers
to the number of laser passes the printer uses per inch to create an image.
This is commonly referred to as dots per inch. A low resolution desktop
laser printer would typically print at 300 dots per inch, whereas a high
resolution imagesetter would typically be capable of printing at 3600
dots per inch. Just to indicate the difference between lpi, ppi (pixels
per inch) and dpi . . . a 600 dpi printer could print a 300 ppi image
at 100 lpi screen frequency.
Q: What
resolution
should my photos be?
A: The rule of thumb is that the pixels per inch of the graphic at actual
reproduction size should be twice the screen frequency of the printed
piece. For example, if the image is going to be printed at 150 lpi on
a press, the graphic should be 300 ppi at reproduction size.
Q: What is a
vector graphic
as opposed to a bitmapped graphic?
A: A vector graphic is an image which shape, position, colour, density,
etc. is described in the Postscript language and is therefore scalable
and resolution independent. A bitmapped image is described in pixels and
when scaled up the pixels are enlarged and can show a jagged edge if enlarged
beyond the optimum size. Using the drawing tools in Adobe Illustrator,
Macromedia Freehand and CorelDraw creates vector images. Scanning and
creating images in bitmap programs such as Adobe Photoshop creates bitmapped
images.
Q: What are
the preferred formats for graphic images
and photos in jobs to be submitted to Samco?
A: We prefer .tif files for four colour process bitmapped images and .eps
for vector images. .JPG and .PDF files can also be used as graphic formats
for some of our devices, but it is best to call our technical support
staff to confirm suitability for the printing process before submitting
these formats.
Q: What native
application programs does Samco support
for full colour printing?
A: Samco supports native files from QuarkXpress, Adobe Pagemaker, Adobe
InDesign, Adobe Photoshop, Adobe Illustrator, Adobe Acrobat, CorelDraw,
and more. (call our technical support staff if you are unsure of your
application). Almost any application can be used for digital printing,
although in some cases it is necessary to create a .prn file or a postscript
file (full technical support is available to help you). Because some
applications do not support colour separation, offset printing presents
some obstacles to programs not designed for graphic reproduction. Some
programs such as Microsoft Publisher, Microsoft Word, Microsoft Powerpoint
and CorelDraw behave inconsistently in a graphic reproduction environment
and therefore may be subject to additional filehandling surcharges.
Q: How do I
write a postscript file
(or print to disk)?
A: Sending a postscript file for your print job generally eliminates problems
with missing fonts and graphics, unsupported applications or platforms.
Click here for detailed instructions on how to create
a postscript file.
Q: Do you
accept Mac or PC files?
A: Samco supports both platforms, as well as postscript files from almost
any platform.
Q: How do I get
my files
to Samco?
A: You can save time and money by uploading your files directly from the
"Place a Print Order" section of
this website. Samco also supports a wide variety of data carriers such
as 3.5" floppy diskettes, ZIP100 disks, ZIP250 disks, JAZ1GB disks,
JAZ2GB disks and CD-ROMs.
Q: Do you support
.PDF files?
A: Samco supports .PDF files for digital printing. Because .PDF files
are Postscript Level 3 files, some of our earlier devices such as the
Xerox DocuTech require some filehandling to step the files down to an
earlier level of Postscript.
Q: Are there
any guidelines
I should follow when I submit a job to you on disk?
A: Please include a hardcopy of your job (colour separated prints as well
as a composite print with multicolour jobs). If you have not converted
fonts to outlines or curves, include the fonts as well. If the graphics
are linked (preferred) and not embedded in the page layout program, be
sure to include the graphics as well.
Q: What
is meant by weight of paper?
A: The thickness of paper is measured by the weight. (The weight of a
type of paper is determined by the weight of a ream (500 sheets) of the
parent-sized sheet of that type of paper. Bonds, offset or book papers
and cover stocks all have different sized parent sheets, so their weights
are specific to their types). All this can be confusing to the lay person,
but here are some practical hints: Bonds are commonly used for copying
and economy print jobs. The most economical and lightest bond commonly
used is 20 lb., with 24 and 32 lb. bond being heavier. The offset, or
book, papers have a finish designed specifically for offset printing with
the most common being 60 lb. (similar to 24 lb. bond) with 70 lb. and
80 lb. being the most common heavier grades used. Coated book stocks have
a clay coating that can be gloss or matte and are designed to be used
in high end spot and process colour printing. Cover stock is much heavier
and stiffer than either bond or book stock. The most common grades of
cover stock are 90, 100 and 120 lb. Cover stock can also be uncoated,
matte coated or gloss coated either coated on one or two sides. These
covers are often measured by actual thickness or caliper and are referred
to in points (10 point = 0.010" thick). The point thickness roughly
corresponds to the weight, i.e., 12 pt is often 120 lb.
If you have a question that is not addressed above, please contact Technical Support.
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