Resampling the answer?

Hi, folks...I'm new here and have a question. A friend of mine is
finishing work on a history of a southern city. She recently had the
opportunity to scan a number of one-of-a-kind documents and photos, all
of which are now back in the hands of the people kind enough to share
them. She now realizes that she scanned some at 200
dpi...unfortunately, her publisher requested 300 dpi. How can she
tweak her files to the required dpi? I have wandered around the web a
bit this afternoon and resampling looks like an answer...I have PS 7.
On the other hand, I have heard good things about PI and QPhoto. Your
thoughts?

NearAustin wrote:
Hi, folks...I'm new here and have a question. A friend of mine is
finishing work on a history of a southern city. She recently had the
opportunity to scan a number of one-of-a-kind documents and photos, all
of which are now back in the hands of the people kind enough to share
them. She now realizes that she scanned some at 200
dpi...unfortunately, her publisher requested 300 dpi. How can she
tweak her files to the required dpi? I have wandered around the web a
bit this afternoon and resampling looks like an answer...I have PS 7.
On the other hand, I have heard good things about PI and QPhoto. Your
thoughts?

Are these photos going to be published at the same size as the
originals or at a smaller size? If they are going to be printed
smaller then you might well be able to hit 300ppi without up sampling.

If the publisher had any sense, and often they do not, they would want
the images at the highest quality and do the re sampling themselves.
Unless you know the exact size they will be printed at there is really
no point in having them at any give ppi.

Scott

NearAustin wrote:
Hi, folks...I'm new here and have a question. A friend of mine is
finishing work on a history of a southern city. She recently had the
opportunity to scan a number of one-of-a-kind documents and photos, all
of which are now back in the hands of the people kind enough to share
them. She now realizes that she scanned some at 200
dpi...unfortunately, her publisher requested 300 dpi. How can she
tweak her files to the required dpi? I have wandered around the web a
bit this afternoon and resampling looks like an answer...I have PS 7.
On the other hand, I have heard good things about PI and QPhoto. Your
thoughts?

Resampling is not the best way to do things, but resampling will work.
Ask the publisher what size they want to publish the documents, if you
are in luck they will just need a resize from 200 and 300 ppi, Other
wise resample them PS7 using bicubic is very good the bicubic
algorithms are so much better in 7 than 5.5 or 6. Again not the best
way to do things, the size change is not that great so you're probably
fine. Just don't tell the publisher unless you have to cause the
printer may freak out.

Tom

NearAustin wrote:
: Hi, folks...I'm new here and have a question. A friend of mine is
: finishing work on a history of a southern city. She recently had the
: opportunity to scan a number of one-of-a-kind documents and photos, all
: of which are now back in the hands of the people kind enough to share
: them. She now realizes that she scanned some at 200
: dpi...unfortunately, her publisher requested 300 dpi. How can she
: tweak her files to the required dpi? I have wandered around the web a
: bit this afternoon and resampling looks like an answer...I have PS 7.
: On the other hand, I have heard good things about PI and QPhoto. Your
: thoughts?

Are you needing to send these images to the publisher with a specific
print size (4x5, 3x5, etc) or is the image print size ignored? If the
image print size is spelled out, yes you will have to upsample to change
the dpi while keeping the print size the same. But if there is no specific
print size required, you can change the dpi without resampling the image.
Making a change to the dpi tag without resampling will leave the image
data unchanged and should (depending on the software you are using) resave
the image with no additional compression artifacts. But if you change the
data (upsampling) you will not only have artifacts from the upsample
operation but also additional artifacts from the recompression. In most
cases such additional changes to the image data would probably not be
overly noticable for this one operation, but there will be changes. So I
would suggest avoiding resampling and resaving as much as you possibly
can.

I am not sure which programs will allow the change of the dpi tag without
a recompression of the image data and which programs recompress anyway.
Maybe someone else will have more specific info or suggestions for you
about this.

Randy

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Randy Berbaum
Champaign, IL