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dpi=ppi?

 
 
Roland Karlsson
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      12-12-2003
http://www.velocityreviews.com/forums/(E-Mail Removed) (didi) wrote in news:ea346cec.0312121359.6b0527c0
@posting.google.com:

> Ok, I am not sure what I need to do now. For a specific goal, I need a
> pic that's 300x300 pixels and I was told I needed to scan it with a
> resolution of 150 dpi and the file size cannot exceed 62MB. How do I
> do that?


A 300x300 pixel large picture scanned at 150 dpi means that
the orignal is 2x2 inch large (or rather small). The resulting
file will be much, much, much smaller than 62 MB.


Roland
 
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Ray Murphy
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      12-13-2003

----------
In article <Xns945055499BFrolandkarlssonchello@130.133.1.4> , Roland
Karlsson <(E-Mail Removed)> wrote:


>(E-Mail Removed) (didi) wrote in news:ea346cec.0312121359.6b0527c0
>@posting.google.com:
>
>> Ok, I am not sure what I need to do now. For a specific goal, I need a
>> pic that's 300x300 pixels and I was told I needed to scan it with a
>> resolution of 150 dpi and the file size cannot exceed 62MB. How do I
>> do that?

>
>A 300x300 pixel large picture scanned at 150 dpi means that
>the orignal is 2x2 inch large (or rather small). The resulting
>file will be much, much, much smaller than 62 MB.
>
>Roland


RM: Yes, a 300 x 300 pixel image (in RGB) is 264k (1/4MB - not 62
MB).
It sounds like you are completely lost, so tell us:
* How big is the image supposed to be (in inches or cm)?
* Is it colour or B+W?
* What is it for - professional printing, laser printing or just a
photo?
* Do you have to enlarge or reduce the image after you scan it?

Ray

 
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Canopus
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      12-13-2003

"Jim Townsend" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> didi wrote:
>
> > Thank you all for the answers. In my case I was talking about just a
> > picture resolution for a scanner. I scanned a pic with 300 dpi setting
> > and when I look at it in photoshop it says 96 ppi. I was wondering if
> > it was screwed up.

>
> Ha.. More confusion between DPI and PPI
>
> Your Photoshop plugged in a default PPI value.. Unless it actually sees a
> predefined PPI value when loading an image file it inserts a default. In

your
> case, your Photoshop inserted a value of 96. Some versions insert 72.
>
> Note you can edit the PPI.. If you'd prefer the image to be 300 PPI, then

just
> type in 300. If you want it to be 172 PPI, the change it to 172. Easy

huh
>
> Be aware that if you scan a 6 inch wide document at 300 dpi, you get an

image
> that's 6" x 300 pixels = 1800 pixels wide.
>
> This image has 1800 pixels, but there are *no pixels per inch*.. Yet.
>
> PPI is meaningless until you actually print your image on paper. The

*inch* in
> pixels per 'inch' stands for an inch of paper.


No no no. PPI stands for pixels per inch, the inch being a virtual inch on
the screen, it has nothing to do with paper. DPI is dots per (real) inch
which is your printer resolution. Here's a little on resolution
http://www.scantips.com/no72dpi.html You'll find some other interesting
info on this site.


>
> When you set the PPI value in an image file, all you are doing is

supplying
> instructions for your printer. The actual number of pixels in the file

and
> their orientation and how they look are unchanged. PPI makes no

difference on
> how an image looks on a monitor.. PPI is *only* a printing term.


You have everything back to front, it's DPI that makes no difference to how
your image looks on your monitor. Look at the above link which will
actually prove it graphicaly.

Rob


 
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imbsysop
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      12-13-2003

"Canopus" <(E-Mail Removed)> wrote in message
news:bre27h$2e1bm$(E-Mail Removed)-berlin.de...
>
> "Jim Townsend" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
> > didi wrote:
> >
> > > Thank you all for the answers. In my case I was talking about just a
> > > picture resolution for a scanner. I scanned a pic with 300 dpi setting
> > > and when I look at it in photoshop it says 96 ppi. I was wondering if
> > > it was screwed up.

> >
> > Ha.. More confusion between DPI and PPI
> >
> > Your Photoshop plugged in a default PPI value.. Unless it actually sees

a
> > predefined PPI value when loading an image file it inserts a default.

In
> your
> > case, your Photoshop inserted a value of 96. Some versions insert 72.
> >
> > Note you can edit the PPI.. If you'd prefer the image to be 300 PPI,

then
> just
> > type in 300. If you want it to be 172 PPI, the change it to 172. Easy

> huh
> >
> > Be aware that if you scan a 6 inch wide document at 300 dpi, you get an

> image
> > that's 6" x 300 pixels = 1800 pixels wide.
> >
> > This image has 1800 pixels, but there are *no pixels per inch*.. Yet.
> >
> > PPI is meaningless until you actually print your image on paper. The

> *inch* in
> > pixels per 'inch' stands for an inch of paper.

>
> No no no. PPI stands for pixels per inch, the inch being a virtual inch

on
> the screen, it has nothing to do with paper...


... if so any "resolution" above say something like 133 PPI makes no sense
'cos yr screen dotpitch (screen raster) is technically never higher ..ie you
cannot represent anything higher in resolution just by downsampling through
the screen video driver .. so I think you are wrong




 
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Ray Murphy
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Posts: n/a
 
      12-13-2003

----------
In article <bre27h$2e1bm$(E-Mail Removed)-berlin.de>, "Canopus"
<(E-Mail Removed)> wrote:


>
>"Jim Townsend" <(E-Mail Removed)> wrote in message
>news:(E-Mail Removed)...
>> didi wrote:
>>
>> > Thank you all for the answers. In my case I was talking about just a
>> > picture resolution for a scanner. I scanned a pic with 300 dpi setting
>> > and when I look at it in photoshop it says 96 ppi. I was wondering if
>> > it was screwed up.

>>
>> Ha.. More confusion between DPI and PPI
>>
>> Your Photoshop plugged in a default PPI value.. Unless it actually sees a
>> predefined PPI value when loading an image file it inserts a default. In

>your
>> case, your Photoshop inserted a value of 96. Some versions insert 72.
>>
>> Note you can edit the PPI.. If you'd prefer the image to be 300 PPI, then

>just
>> type in 300. If you want it to be 172 PPI, the change it to 172. Easy

>huh
>>
>> Be aware that if you scan a 6 inch wide document at 300 dpi, you get an

>image
>> that's 6" x 300 pixels = 1800 pixels wide.
>>
>> This image has 1800 pixels, but there are *no pixels per inch*.. Yet.
>>
>> PPI is meaningless until you actually print your image on paper. The

>*inch* in
>> pixels per 'inch' stands for an inch of paper.

>
>No no no. PPI stands for pixels per inch, the inch being a virtual inch on
>the screen, it has nothing to do with paper. DPI is dots per (real) inch
>which is your printer resolution. Here's a little on resolution
>http://www.scantips.com/no72dpi.html You'll find some other interesting
>info on this site.



RM: Nice web page, but useless for teaching the concept quickly.
If anyone still doesn't understand what's going on:-
========================
* Pixel = Picture cell on a monitor
* Pixel = Picture cell in Photoshop
* 72 PPI in relation to monitors = 1 inch on a 72 ppi monitor.
* 72 PPI in relation to printing = 1 inch print for each 72 pixels
* 96 PPI in relation to monitors = 1 inch on a 96 ppi monitor.
* 96 PPI in relation to printing = 1 inch print for each 96 pixels.
* DPI has got nothing to do with monitors.
* Pixels / ppi = image size on paper.
========================

>> When you set the PPI value in an image file, all you are doing is

>supplying
>> instructions for your printer. The actual number of pixels in the file

>and
>> their orientation and how they look are unchanged. PPI makes no

>difference on
>> how an image looks on a monitor.. PPI is *only* a printing term.

>
>You have everything back to front, it's DPI that makes no difference to how
>your image looks on your monitor. Look at the above link which will
>actually prove it graphicaly.


RM: Yes, DPI has nothing whatever to do with monitors. The confusion
has been caused by incorect terminology.
>
>Rob


Ray
 
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Ray Murphy
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Posts: n/a
 
      12-13-2003

----------
In article <bresks$9c5$(E-Mail Removed)>, "imbsysop"
<(E-Mail Removed)> wrote:


>
>"Canopus" <(E-Mail Removed)> wrote in message
>news:bre27h$2e1bm$(E-Mail Removed)-berlin.de...
>>
>> "Jim Townsend" <(E-Mail Removed)> wrote in message
>> news:(E-Mail Removed)...
>> > didi wrote:
>> >
>> > > Thank you all for the answers. In my case I was talking about just a
>> > > picture resolution for a scanner. I scanned a pic with 300 dpi setting
>> > > and when I look at it in photoshop it says 96 ppi. I was wondering if
>> > > it was screwed up.
>> >
>> > Ha.. More confusion between DPI and PPI
>> >
>> > Your Photoshop plugged in a default PPI value.. Unless it actually sees

>a
>> > predefined PPI value when loading an image file it inserts a default.

>In
>> your
>> > case, your Photoshop inserted a value of 96. Some versions insert 72.
>> >
>> > Note you can edit the PPI.. If you'd prefer the image to be 300 PPI,

>then
>> just
>> > type in 300. If you want it to be 172 PPI, the change it to 172. Easy

>> huh
>> >
>> > Be aware that if you scan a 6 inch wide document at 300 dpi, you get an

>> image
>> > that's 6" x 300 pixels = 1800 pixels wide.
>> >
>> > This image has 1800 pixels, but there are *no pixels per inch*.. Yet.
>> >
>> > PPI is meaningless until you actually print your image on paper. The

>> *inch* in
>> > pixels per 'inch' stands for an inch of paper.

>>
>> No no no. PPI stands for pixels per inch, the inch being a virtual inch

>on
>> the screen, it has nothing to do with paper...

>
>.. if so any "resolution" above say something like 133 PPI makes no sense
>'cos yr screen dotpitch (screen raster) is technically never higher ..ie you
>cannot represent anything higher in resolution just by downsampling through
>the screen video driver .. so I think you are wrong


RM: That's right, we can only see the number of pixels per inch which
an individual monitor displays.
A 72 ppi monitor will display 72 pixels in an inch; a 96 ppi monitor
will display 96 pixels per inch etc.
This means that if we are looking at (for example) a 144 ppi image on
a 72 ppi monitor, we will see the 144 pixels in 2 inches.

Ray

 
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didi
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      12-13-2003
Here are my specifications:
This image must be in the Joint Photographic Experts Group (JPEG) File
Interchange Format (JFIF) format. If the image is created by using a
digital camera, it must have a resolution of 320 by 240 pixels, with
either 24-bits of color, 8-bits of color or 8-bits of gray. If the
image is created by scanning a photographic print the original print
must have been 2" by 2" (50mm x 50mm), and the scan must be performed
at a resolution of 150 dots per inch (dpi); the image must have a
resolution of 300 by 300 pixels, with either 24-bits of color, 8-bits
of color or 8-bits of gray. The image can not exceed 62,500 bytes
(62.5KB) in size.

In my case, I am scanning a pic that's about 4cmx5cm.

"Ray Murphy" <(E-Mail Removed)> wrote in message news:<(E-Mail Removed)>...
> ----------
> In article <Xns945055499BFrolandkarlssonchello@130.133.1.4> , Roland
> Karlsson <(E-Mail Removed)> wrote:
>
>
> >(E-Mail Removed) (didi) wrote in news:ea346cec.0312121359.6b0527c0
> >@posting.google.com:
> >
> >> Ok, I am not sure what I need to do now. For a specific goal, I need a
> >> pic that's 300x300 pixels and I was told I needed to scan it with a
> >> resolution of 150 dpi and the file size cannot exceed 62MB. How do I
> >> do that?

> >
> >A 300x300 pixel large picture scanned at 150 dpi means that
> >the orignal is 2x2 inch large (or rather small). The resulting
> >file will be much, much, much smaller than 62 MB.
> >
> >Roland

>
> RM: Yes, a 300 x 300 pixel image (in RGB) is 264k (1/4MB - not 62
> MB).
> It sounds like you are completely lost, so tell us:
> * How big is the image supposed to be (in inches or cm)?
> * Is it colour or B+W?
> * What is it for - professional printing, laser printing or just a
> photo?
> * Do you have to enlarge or reduce the image after you scan it?
>
> Ray

 
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Ray Murphy
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Posts: n/a
 
      12-13-2003
[ L - O - N - G ]
----------
In article <brdg9q$2kj$(E-Mail Removed)>, "imbsysop"
<(E-Mail Removed)> wrote:


>
>"Ray Murphy" <(E-Mail Removed)> wrote in message
>news:(E-Mail Removed)...
>>

>snip ..
>> >
>> >I was merely trying to pointout that AFAIK people in EU were also
>> >using PPI/DPI and *not* PPcm or DPcm ..

>>
>> RM: That is what I was trying to correct. The printing industry, which
>> has been using digital images long before digital cameras became
>> popular, have been using LPI (Lines per inch) or L/cm (Lines per cm)
>> for halftone screens - probably for about a hundred years.

>
>thnx for the extensive clarification but you got me kind of confused
>'cos I have some friends who work in the (book)printing business and all I
>hear them talk about are picas and points and inches .. never cm ..
>all the printers I have used in our research institute over the years were
>always "stepping" in fractions of inches never metric so I wonder if despite
>that there is no international standard, there might very well be a de facto
>usage standard after all ..? just FWIW


RM: I could simplify my answer, but a longer one will tell you more
and also be interesting.
In Australia for example we were using imperial (English) measurements
until about the mid 1970's, and as you know, printers had their own
measuring system.

We measured the vertical height of type (as read on a page) in
"points" - with 72 points to the inch.
In the 1800's type was not measured in any scientific way. It was
known by name only - with such names as "Brilliant, Diamond, Pearl,
Agate, Nonpareil, Minion, Brevier, Bourgeois, Long Primer, Small Pica,
Pica"-- plus ten others.
The above names are in sequence from tiny to larger (about 3 point to
12 point).

The fount (or printing typeface) called "Pica" which was "12 point
type" in today's language was very well known and everyone could
visualise it. It had (approximately) 6 lines to the inch and it's
name was used to create an "industry standard" to indicate
measurements more conveniently amongst printers.

The fount named Pica, besides having a convenient 6 lines to the inch
vertically, had another convenient attribute - the width of the lower
-case "m" was also about 1/6th of an inch, and the width of the
lower-case "n" was half of that (1/12th of an inch).
The new standard brought in new words which helped printers measure
both vertically and horizontally. The new measure was a "pica em" and
also a "pica en" which were 1/6 inch and 1/12 inch (or 12 points and 6
points respectively).

This meant that printers (probably in every country) were able to
measure their type in a very convenient way - with increments that
were not too small or not too large. For example a small book might
have had a type width of 30 ems (5 inches) or a newspaper column might
have been 8 and a half ems (or 19 ens wide). Everyone was happy with
this.
When we (and I mean myself here too) assembled thousands of single
letters and spaces into lines of type in a "composing stick" - a small
tray which holds about10 lines of type, with a scale engraved with a
mark for every em and en. This enabled us to place a moving block up
to the required mark to "box-in" the type to a maximum length.
We *never* composed type to any length except ems or ens - or more
correctly - Pica ems and ens. Normally one would say "18 and a half
picas" for a column width, rather than say "37 ens" or "18 picas, 1
en".

The new "Pica" measurement was also sub-divided into "points" - with 6
points to the Pica em - or 72 points to the inch.
These measurements were mostly for vertical measure, and we used lead
"spacers" which came in these thicknesses - 1pt, 2 pt, 3 pt, 6 pt, 12
pt, 18 pt, 24 pt plus other larger material which was used for
spacing.
We might for example have wanted to set a job in 8 point type with
extra 1 point of spacing between each line. This meant that we placed
a "1 point lead" on top of the first line of type after we had
hand-set it.
You must understand that all of this was done upside-down, and also
inside out (because the type is reversed from what is printed). This
means that the first "lead" was being placed below the first line when
the job was seen "right way up" afterwards.

When automatic processes were introduced, such as Mergenthaler's
Linotype machine - which set single lines of lead type 30 ems long
(from minute brass moulds of each letter) , everything remained
compatible and the old measurements were retained because it was the
*only* way to go.
Even when VRG-Compugraphic introduced their hard-wired computers which
photographed single letters from a spinning film strip onto photo
paper we retained our measuring system.
Inches were only ever used when they *needed* to be used. No one had
to tell anyone when it was appropriate to use inches because it was
obvious to all.

When the metric system was introduced in Australia in the 1970's we
used the new centimetres and millimetres only when absolutely
necessary, but gadually we got used to it.

As Offset Printing began to replace Letterpress Printing, we started
to do the "paste-up" of artwork with large film grids on light tables
with a 1mm spaced graph image, with 5 and 10 mm thicker lines. This of
course was completely incompatble for "thinking" in inches. It was too
late to get new layout graphs which were spaced with 1/8 inch lines
and 1/2 inch lines etc., because metric measuring had arrived.

This new metric system created a problem straight away with business
cards, because they were always 3 and a half inches x 2 and one eighth
inches. This translated into 88.9mm x 53.9mm (or 89 x 54mm).
The width of the type across the card was always 3 inches. This
translated into 76.2mm - thus leaving 13mm of space (6.5mm on either
side). None of this was workable in real-life and we basically had to
fight for the right to alter the layout to an all-metric one.

In my own case I just ignored instructions and ordered all business
card type to be set to 80mm instead of 18 ems ems and then made the
margins 5mm. This corresponded with the layout grid perfectly. The
size of the card were altered to 90 x 55 instead of using 89 x 54. All
of this prevented spacing errors - particularly if you were printing
10 at a time etc.

When the early Macs came out it was the first time we could actually
SEE any type being set by a computer. Prior to that everything was to
be kept in memory [your own memory].
In the case of the Monophoto film typesetter they had a small "coffee
tin" up the top with hundreds of numbers printed on it, and a moving
brass arrow. This told the operator when he was reaching the end of a
line or whatever!

The early VRG hard-wired computer which was about the size of a
clothes drying cabinet was pretty radical in it's day because it had
"LEDS". With this computer, typesetting was done on a keyboard
attached to a "pop-riveted" unpainted metal box with 8 LEDS which lit
up at certain times according to where you were up to in the job, but
as I said - everything was in your own memory, and if you didn't get
it right, corrections had to be set and cut-in to the photo paper with
a scalpel.

Oh, I've just remembered - one computer before the Mac provided one
line of type which was displayed in multiple red dots to roughly
outline each character. That machine wasn't so bad really because if
you thought you made an error, you could always "read" the long
punched paper tape which got spewed out all over the floor next to
you, but it wasn't easy to learn what a bunch of holes meant :- (

[Repeat of your text above]
>thnx for the extensive clarification but you got me kind of confused
>'cos I have some friends who work in the (book)printing business and all I
>hear them talk about are picas and points and inches .. never cm ..
>all the printers I have used in our research institute over the years were
>always "stepping" in fractions of inches never metric so I wonder if despite
>that there is no international standard, there might very well be a de facto
>usage standard after all ..? just FWIW


I can see that if they were not using metric measurements in your
country, then of *of course* they would be using fractions of an inch
- presumably 1/2; 1/8 and 1/16th of an inch - whenever printers'
measures were unsuitable.
Your friends would not have been exposed to anything much which was
metric.

One interesting thing which also happened to me after the Mac came out
was that even though I could easily visualise point sizes for deciding
upon border or line thicknesses, I always prefer to "think" in mm for
very small measures. Of course it gives one a better range as well -
..1 mm, .2mm, .3mm, .4mm etc.

L - o - n - g story here, but it covers quite a few angles and may
explain to some extent where our computer terms come from (Ems, Points
and Leading). Ems, or more precisely "Pica ems" (or Picas for sort)
have become almost defunct in Australia, although they are still used
for letterpress printing because they are necessary.

Getting back to the question of halftone screens which are measured in
LPI and also LPC, and also the accompanying PPI for each of them (2
for each halftone dot) - I cannot imagine that in the long run DPI,
PPI, SPI or LPI could remain a long-term standard or ever become an
International Standard because the language of science is metric, and
to impose an almost defunct measuring system on the modern world would
be ludicrous (and ignored in metric countries).
I would imagine that as soon as the U.S. changes over to metric the
"competition" will disappear and an International Standard will be
set.

Ray

..








 
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Ray Murphy
Guest
Posts: n/a
 
      12-13-2003

----------
In article <(E-Mail Removed) >,
(E-Mail Removed) (didi) wrote:

>
>"Ray Murphy" <(E-Mail Removed)> wrote in message
>news:<(E-Mail Removed)>...
>> ----------
>> In article <Xns945055499BFrolandkarlssonchello@130.133.1.4> , Roland
>> Karlsson <(E-Mail Removed)> wrote:
>>
>>
>> >(E-Mail Removed) (didi) wrote in news:ea346cec.0312121359.6b0527c0
>> >@posting.google.com:
>> >
>> >> Ok, I am not sure what I need to do now. For a specific goal, I need a
>> >> pic that's 300x300 pixels and I was told I needed to scan it with a
>> >> resolution of 150 dpi and the file size cannot exceed 62MB. How do I
>> >> do that?
>> >
>> >A 300x300 pixel large picture scanned at 150 dpi means that
>> >the orignal is 2x2 inch large (or rather small). The resulting
>> >file will be much, much, much smaller than 62 MB.
>> >
>> >Roland

>>
>> RM: Yes, a 300 x 300 pixel image (in RGB) is 264k (1/4MB - not 62
>> MB).
>> It sounds like you are completely lost, so tell us:
>> * How big is the image supposed to be (in inches or cm)?
>> * Is it colour or B+W?
>> * What is it for - professional printing, laser printing or just a
>> photo?
>> * Do you have to enlarge or reduce the image after you scan it?
>>
>> Ray


>Here are my specifications:


RM: Ok, I'm with you now.

>This image must be in the Joint Photographic Experts Group (JPEG) File
>Interchange Format (JFIF) format.


RM: This means that if you scanned your photo and saved it as a Tiff
file you must re-save it as a JPEG before submitting it.

>If the image is created by using a
>digital camera, it must have a resolution of 320 by 240 pixels, with
>either 24-bits of color, 8-bits of color or 8-bits of gray.


RM: This means that your final image must be precisely this size. If
it is in colour you can save it as 8 bit or 24 bit, or if it is in
black+white it must be saved in the normal B+W mode of 256 colours
(shades of grey).

>If the image is created by scanning a photographic print the original print
>must have been 2" by 2" (50mm x 50mm), and the scan must be performed
>at a resolution of 150 dots per inch (dpi);


RM: This indicates a different sizeis required to the digital camera
image. They want a 50 x 50mm print scanned, but you only have a 40 x
50mm print. This means that you must either (a) Make a bigger print
and CROP it after scanning to 50 x 50 mm or (b) Give them your image
at it's current size (after you have "straightened the edges" by
cropping just inside the perimeter).
They are saying that you MUST set your scanner at 150 pixels per inch.
(Ignore dpi - it's an incorrect term).

>the image must have a
>resolution of 300 by 300 pixels, with either 24-bits of color, 8-bits
>of color or 8-bits of gray. The image can not exceed 62,500 bytes
>(62.5KB) in size.


RM: They are saying that you must use a scanner which is set for 300
ppi or 300 spi (samples per inch) - same thing.
This means you must not use (for example) a 600 ppi scan - which will
sometimes have 300 pixels in one direction and 600 pixels in the
other.
The scanner must be set for 8 bit or 24 bit colour (or alternatively,
ordinary grayscale - which is 8 bit or 256 shades).
>
>In my case, I am scanning a pic that's about 4cmx5cm.


RM: A 50 x 50mm scan at 150 ppi scanning in RGB will be 255k as a Tiff
file, but will get smaller when saved as a JPEG at the highest
quality.
Your 40 x 50mm print at150 ppi scanning in RGB will be230k as a Tiff
file.

I suggest that you make a start and see what happens AND also make
detailed notes of exactly what you do and then tell us.

[ideas]
* Place pic in scanner
* Set for 16 bit colour (if avail).
* Set for 150 ppi scanning
* Select area to scan (larger than pic
* Do scan
* Save scan as "Test1.Tif" (or whatever)
* Crop to just inside the image
* Improve pic with Brightness/Contrast etc
* Save again after improvements "Test1.Tif"
* Save As "Test1.jpg" (highest quality only)
* See size of JPEG

Ray






 
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Ray Murphy
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Posts: n/a
 
      12-13-2003

----------
In article <(E-Mail Removed)>, "Ray Murphy"
<(E-Mail Removed)> wrote:


>
>----------
>In article <(E-Mail Removed) >,
>(E-Mail Removed) (didi) wrote:
>
>>
>>"Ray Murphy" <(E-Mail Removed)> wrote in message
>>news:<(E-Mail Removed)>...
>>> ----------
>>> In article <Xns945055499BFrolandkarlssonchello@130.133.1.4> , Roland
>>> Karlsson <(E-Mail Removed)> wrote:
>>>
>>>
>>> >(E-Mail Removed) (didi) wrote in news:ea346cec.0312121359.6b0527c0
>>> >@posting.google.com:
>>> >
>>> >> Ok, I am not sure what I need to do now. For a specific goal, I need a
>>> >> pic that's 300x300 pixels and I was told I needed to scan it with a
>>> >> resolution of 150 dpi and the file size cannot exceed 62MB. How do I
>>> >> do that?
>>> >
>>> >A 300x300 pixel large picture scanned at 150 dpi means that
>>> >the orignal is 2x2 inch large (or rather small). The resulting
>>> >file will be much, much, much smaller than 62 MB.
>>> >
>>> >Roland
>>>
>>> RM: Yes, a 300 x 300 pixel image (in RGB) is 264k (1/4MB - not 62
>>> MB).
>>> It sounds like you are completely lost, so tell us:
>>> * How big is the image supposed to be (in inches or cm)?
>>> * Is it colour or B+W?
>>> * What is it for - professional printing, laser printing or just a
>>> photo?
>>> * Do you have to enlarge or reduce the image after you scan it?
>>>
>>> Ray

>
>>Here are my specifications:

>
>RM: Ok, I'm with you now.
>
>>This image must be in the Joint Photographic Experts Group (JPEG) File
>>Interchange Format (JFIF) format.

>
>RM: This means that if you scanned your photo and saved it as a Tiff
>file you must re-save it as a JPEG before submitting it.
>
>>If the image is created by using a
>>digital camera, it must have a resolution of 320 by 240 pixels, with
>>either 24-bits of color, 8-bits of color or 8-bits of gray.

>
>RM: This means that your final image must be precisely this size. If
>it is in colour you can save it as 8 bit or 24 bit, or if it is in
>black+white it must be saved in the normal B+W mode of 256 colours
>(shades of grey).
>
>>If the image is created by scanning a photographic print the original print
>>must have been 2" by 2" (50mm x 50mm), and the scan must be performed
>>at a resolution of 150 dots per inch (dpi);

>
>RM: This indicates a different sizeis required to the digital camera
>image. They want a 50 x 50mm print scanned, but you only have a 40 x
>50mm print. This means that you must either (a) Make a bigger print
>and CROP it after scanning to 50 x 50 mm or (b) Give them your image
>at it's current size (after you have "straightened the edges" by
>cropping just inside the perimeter).
>They are saying that you MUST set your scanner at 150 pixels per inch.
>(Ignore dpi - it's an incorrect term).
>
>>the image must have a
>>resolution of 300 by 300 pixels, with either 24-bits of color, 8-bits
>>of color or 8-bits of gray. The image can not exceed 62,500 bytes
>>(62.5KB) in size.

>
>RM: They are saying that you must use a scanner which is set for 300
>ppi .......... [WRONG]


RM: Geez, no wonder you are finding it hard. I got confused myself
there.
They are saying that a scanned photo must have a final size of 300 x
300 pixels (which is a different requirement to a digital camera image
of 320 x 240)

[rest snipped]

Ray
 
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